/* Build expressions with type checking for C compiler. Copyright (C) 1987, 1988, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002 Free Software Foundation, Inc. This file is part of GCC. GCC is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. GCC is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with GCC; see the file COPYING. If not, write to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ /* This file is part of the C front end. It contains routines to build C expressions given their operands, including computing the types of the result, C-specific error checks, and some optimization. There are also routines to build RETURN_STMT nodes and CASE_STMT nodes, and to process initializations in declarations (since they work like a strange sort of assignment). */ #include "config.h" #include "system.h" #include "rtl.h" #include "tree.h" #include "c-tree.h" #include "tm_p.h" #include "flags.h" #include "output.h" #include "expr.h" #include "toplev.h" #include "intl.h" #include "ggc.h" #include "target.h" /* Nonzero if we've already printed a "missing braces around initializer" message within this initializer. */ static int missing_braces_mentioned; /* 1 if we explained undeclared var errors. */ static int undeclared_variable_notice; static tree qualify_type PARAMS ((tree, tree)); static int comp_target_types PARAMS ((tree, tree, int)); static int function_types_compatible_p PARAMS ((tree, tree)); static int type_lists_compatible_p PARAMS ((tree, tree)); static tree decl_constant_value_for_broken_optimization PARAMS ((tree)); static tree default_function_array_conversion PARAMS ((tree)); static tree lookup_field PARAMS ((tree, tree)); static tree convert_arguments PARAMS ((tree, tree, tree, tree)); static tree pointer_diff PARAMS ((tree, tree)); static tree unary_complex_lvalue PARAMS ((enum tree_code, tree, int)); static void pedantic_lvalue_warning PARAMS ((enum tree_code)); static tree internal_build_compound_expr PARAMS ((tree, int)); static tree convert_for_assignment PARAMS ((tree, tree, const char *, tree, tree, int)); static void warn_for_assignment PARAMS ((const char *, const char *, tree, int)); static tree valid_compound_expr_initializer PARAMS ((tree, tree)); static void push_string PARAMS ((const char *)); static void push_member_name PARAMS ((tree)); static void push_array_bounds PARAMS ((int)); static int spelling_length PARAMS ((void)); static char *print_spelling PARAMS ((char *)); static void warning_init PARAMS ((const char *)); static tree digest_init PARAMS ((tree, tree, int)); static void output_init_element PARAMS ((tree, tree, tree, int)); static void output_pending_init_elements PARAMS ((int)); static int set_designator PARAMS ((int)); static void push_range_stack PARAMS ((tree)); static void add_pending_init PARAMS ((tree, tree)); static void set_nonincremental_init PARAMS ((void)); static void set_nonincremental_init_from_string PARAMS ((tree)); static tree find_init_member PARAMS ((tree)); /* Do `exp = require_complete_type (exp);' to make sure exp does not have an incomplete type. (That includes void types.) */ tree require_complete_type (value) tree value; { tree type = TREE_TYPE (value); if (value == error_mark_node || type == error_mark_node) return error_mark_node; /* First, detect a valid value with a complete type. */ if (COMPLETE_TYPE_P (type)) return value; c_incomplete_type_error (value, type); return error_mark_node; } /* Print an error message for invalid use of an incomplete type. VALUE is the expression that was used (or 0 if that isn't known) and TYPE is the type that was invalid. */ void c_incomplete_type_error (value, type) tree value; tree type; { const char *type_code_string; /* Avoid duplicate error message. */ if (TREE_CODE (type) == ERROR_MARK) return; if (value != 0 && (TREE_CODE (value) == VAR_DECL || TREE_CODE (value) == PARM_DECL)) error ("`%s' has an incomplete type", IDENTIFIER_POINTER (DECL_NAME (value))); else { retry: /* We must print an error message. Be clever about what it says. */ switch (TREE_CODE (type)) { case RECORD_TYPE: type_code_string = "struct"; break; case UNION_TYPE: type_code_string = "union"; break; case ENUMERAL_TYPE: type_code_string = "enum"; break; case VOID_TYPE: error ("invalid use of void expression"); return; case ARRAY_TYPE: if (TYPE_DOMAIN (type)) { if (TYPE_MAX_VALUE (TYPE_DOMAIN (type)) == NULL) { error ("invalid use of flexible array member"); return; } type = TREE_TYPE (type); goto retry; } error ("invalid use of array with unspecified bounds"); return; default: abort (); } if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE) error ("invalid use of undefined type `%s %s'", type_code_string, IDENTIFIER_POINTER (TYPE_NAME (type))); else /* If this type has a typedef-name, the TYPE_NAME is a TYPE_DECL. */ error ("invalid use of incomplete typedef `%s'", IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (type)))); } } /* Given a type, apply default promotions wrt unnamed function arguments and return the new type. */ tree c_type_promotes_to (type) tree type; { if (TYPE_MAIN_VARIANT (type) == float_type_node) return double_type_node; if (c_promoting_integer_type_p (type)) { /* Preserve unsignedness if not really getting any wider. */ if (TREE_UNSIGNED (type) && (TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node))) return unsigned_type_node; return integer_type_node; } return type; } /* Return a variant of TYPE which has all the type qualifiers of LIKE as well as those of TYPE. */ static tree qualify_type (type, like) tree type, like; { return c_build_qualified_type (type, TYPE_QUALS (type) | TYPE_QUALS (like)); } /* Return the common type of two types. We assume that comptypes has already been done and returned 1; if that isn't so, this may crash. In particular, we assume that qualifiers match. This is the type for the result of most arithmetic operations if the operands have the given two types. */ tree common_type (t1, t2) tree t1, t2; { enum tree_code code1; enum tree_code code2; tree attributes; /* Save time if the two types are the same. */ if (t1 == t2) return t1; /* If one type is nonsense, use the other. */ if (t1 == error_mark_node) return t2; if (t2 == error_mark_node) return t1; /* Merge the attributes. */ attributes = (*targetm.merge_type_attributes) (t1, t2); /* Treat an enum type as the unsigned integer type of the same width. */ if (TREE_CODE (t1) == ENUMERAL_TYPE) t1 = c_common_type_for_size (TYPE_PRECISION (t1), 1); if (TREE_CODE (t2) == ENUMERAL_TYPE) t2 = c_common_type_for_size (TYPE_PRECISION (t2), 1); code1 = TREE_CODE (t1); code2 = TREE_CODE (t2); /* If one type is complex, form the common type of the non-complex components, then make that complex. Use T1 or T2 if it is the required type. */ if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE) { tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1; tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2; tree subtype = common_type (subtype1, subtype2); if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype) return build_type_attribute_variant (t1, attributes); else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype) return build_type_attribute_variant (t2, attributes); else return build_type_attribute_variant (build_complex_type (subtype), attributes); } switch (code1) { case INTEGER_TYPE: case REAL_TYPE: /* If only one is real, use it as the result. */ if (code1 == REAL_TYPE && code2 != REAL_TYPE) return build_type_attribute_variant (t1, attributes); if (code2 == REAL_TYPE && code1 != REAL_TYPE) return build_type_attribute_variant (t2, attributes); /* Both real or both integers; use the one with greater precision. */ if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2)) return build_type_attribute_variant (t1, attributes); else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1)) return build_type_attribute_variant (t2, attributes); /* Same precision. Prefer longs to ints even when same size. */ if (TYPE_MAIN_VARIANT (t1) == long_unsigned_type_node || TYPE_MAIN_VARIANT (t2) == long_unsigned_type_node) return build_type_attribute_variant (long_unsigned_type_node, attributes); if (TYPE_MAIN_VARIANT (t1) == long_integer_type_node || TYPE_MAIN_VARIANT (t2) == long_integer_type_node) { /* But preserve unsignedness from the other type, since long cannot hold all the values of an unsigned int. */ if (TREE_UNSIGNED (t1) || TREE_UNSIGNED (t2)) t1 = long_unsigned_type_node; else t1 = long_integer_type_node; return build_type_attribute_variant (t1, attributes); } /* Likewise, prefer long double to double even if same size. */ if (TYPE_MAIN_VARIANT (t1) == long_double_type_node || TYPE_MAIN_VARIANT (t2) == long_double_type_node) return build_type_attribute_variant (long_double_type_node, attributes); /* Otherwise prefer the unsigned one. */ if (TREE_UNSIGNED (t1)) return build_type_attribute_variant (t1, attributes); else return build_type_attribute_variant (t2, attributes); case POINTER_TYPE: /* For two pointers, do this recursively on the target type, and combine the qualifiers of the two types' targets. */ /* This code was turned off; I don't know why. But ANSI C specifies doing this with the qualifiers. So I turned it on again. */ { tree pointed_to_1 = TREE_TYPE (t1); tree pointed_to_2 = TREE_TYPE (t2); tree target = common_type (TYPE_MAIN_VARIANT (pointed_to_1), TYPE_MAIN_VARIANT (pointed_to_2)); t1 = build_pointer_type (c_build_qualified_type (target, TYPE_QUALS (pointed_to_1) | TYPE_QUALS (pointed_to_2))); return build_type_attribute_variant (t1, attributes); } #if 0 t1 = build_pointer_type (common_type (TREE_TYPE (t1), TREE_TYPE (t2))); return build_type_attribute_variant (t1, attributes); #endif case ARRAY_TYPE: { tree elt = common_type (TREE_TYPE (t1), TREE_TYPE (t2)); /* Save space: see if the result is identical to one of the args. */ if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1)) return build_type_attribute_variant (t1, attributes); if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2)) return build_type_attribute_variant (t2, attributes); /* Merge the element types, and have a size if either arg has one. */ t1 = build_array_type (elt, TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2)); return build_type_attribute_variant (t1, attributes); } case FUNCTION_TYPE: /* Function types: prefer the one that specified arg types. If both do, merge the arg types. Also merge the return types. */ { tree valtype = common_type (TREE_TYPE (t1), TREE_TYPE (t2)); tree p1 = TYPE_ARG_TYPES (t1); tree p2 = TYPE_ARG_TYPES (t2); int len; tree newargs, n; int i; /* Save space: see if the result is identical to one of the args. */ if (valtype == TREE_TYPE (t1) && ! TYPE_ARG_TYPES (t2)) return build_type_attribute_variant (t1, attributes); if (valtype == TREE_TYPE (t2) && ! TYPE_ARG_TYPES (t1)) return build_type_attribute_variant (t2, attributes); /* Simple way if one arg fails to specify argument types. */ if (TYPE_ARG_TYPES (t1) == 0) { t1 = build_function_type (valtype, TYPE_ARG_TYPES (t2)); return build_type_attribute_variant (t1, attributes); } if (TYPE_ARG_TYPES (t2) == 0) { t1 = build_function_type (valtype, TYPE_ARG_TYPES (t1)); return build_type_attribute_variant (t1, attributes); } /* If both args specify argument types, we must merge the two lists, argument by argument. */ pushlevel (0); declare_parm_level (1); len = list_length (p1); newargs = 0; for (i = 0; i < len; i++) newargs = tree_cons (NULL_TREE, NULL_TREE, newargs); n = newargs; for (; p1; p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n)) { /* A null type means arg type is not specified. Take whatever the other function type has. */ if (TREE_VALUE (p1) == 0) { TREE_VALUE (n) = TREE_VALUE (p2); goto parm_done; } if (TREE_VALUE (p2) == 0) { TREE_VALUE (n) = TREE_VALUE (p1); goto parm_done; } /* Given wait (union {union wait *u; int *i} *) and wait (union wait *), prefer union wait * as type of parm. */ if (TREE_CODE (TREE_VALUE (p1)) == UNION_TYPE && TREE_VALUE (p1) != TREE_VALUE (p2)) { tree memb; for (memb = TYPE_FIELDS (TREE_VALUE (p1)); memb; memb = TREE_CHAIN (memb)) if (comptypes (TREE_TYPE (memb), TREE_VALUE (p2))) { TREE_VALUE (n) = TREE_VALUE (p2); if (pedantic) pedwarn ("function types not truly compatible in ISO C"); goto parm_done; } } if (TREE_CODE (TREE_VALUE (p2)) == UNION_TYPE && TREE_VALUE (p2) != TREE_VALUE (p1)) { tree memb; for (memb = TYPE_FIELDS (TREE_VALUE (p2)); memb; memb = TREE_CHAIN (memb)) if (comptypes (TREE_TYPE (memb), TREE_VALUE (p1))) { TREE_VALUE (n) = TREE_VALUE (p1); if (pedantic) pedwarn ("function types not truly compatible in ISO C"); goto parm_done; } } TREE_VALUE (n) = common_type (TREE_VALUE (p1), TREE_VALUE (p2)); parm_done: ; } poplevel (0, 0, 0); t1 = build_function_type (valtype, newargs); /* ... falls through ... */ } default: return build_type_attribute_variant (t1, attributes); } } /* Return 1 if TYPE1 and TYPE2 are compatible types for assignment or various other operations. Return 2 if they are compatible but a warning may be needed if you use them together. */ int comptypes (type1, type2) tree type1, type2; { tree t1 = type1; tree t2 = type2; int attrval, val; /* Suppress errors caused by previously reported errors. */ if (t1 == t2 || !t1 || !t2 || TREE_CODE (t1) == ERROR_MARK || TREE_CODE (t2) == ERROR_MARK) return 1; /* If either type is the internal version of sizetype, return the language version. */ if (TREE_CODE (t1) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t1) && TYPE_DOMAIN (t1) != 0) t1 = TYPE_DOMAIN (t1); if (TREE_CODE (t2) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t2) && TYPE_DOMAIN (t2) != 0) t2 = TYPE_DOMAIN (t2); /* Treat an enum type as the integer type of the same width and signedness. */ if (TREE_CODE (t1) == ENUMERAL_TYPE) t1 = c_common_type_for_size (TYPE_PRECISION (t1), TREE_UNSIGNED (t1)); if (TREE_CODE (t2) == ENUMERAL_TYPE) t2 = c_common_type_for_size (TYPE_PRECISION (t2), TREE_UNSIGNED (t2)); if (t1 == t2) return 1; /* Different classes of types can't be compatible. */ if (TREE_CODE (t1) != TREE_CODE (t2)) return 0; /* Qualifiers must match. */ if (TYPE_QUALS (t1) != TYPE_QUALS (t2)) return 0; /* Allow for two different type nodes which have essentially the same definition. Note that we already checked for equality of the type qualifiers (just above). */ if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2)) return 1; /* 1 if no need for warning yet, 2 if warning cause has been seen. */ if (! (attrval = (*targetm.comp_type_attributes) (t1, t2))) return 0; /* 1 if no need for warning yet, 2 if warning cause has been seen. */ val = 0; switch (TREE_CODE (t1)) { case POINTER_TYPE: val = (TREE_TYPE (t1) == TREE_TYPE (t2) ? 1 : comptypes (TREE_TYPE (t1), TREE_TYPE (t2))); break; case FUNCTION_TYPE: val = function_types_compatible_p (t1, t2); break; case ARRAY_TYPE: { tree d1 = TYPE_DOMAIN (t1); tree d2 = TYPE_DOMAIN (t2); bool d1_variable, d2_variable; bool d1_zero, d2_zero; val = 1; /* Target types must match incl. qualifiers. */ if (TREE_TYPE (t1) != TREE_TYPE (t2) && 0 == (val = comptypes (TREE_TYPE (t1), TREE_TYPE (t2)))) return 0; /* Sizes must match unless one is missing or variable. */ if (d1 == 0 || d2 == 0 || d1 == d2) break; d1_zero = ! TYPE_MAX_VALUE (d1); d2_zero = ! TYPE_MAX_VALUE (d2); d1_variable = (! d1_zero && (TREE_CODE (TYPE_MIN_VALUE (d1)) != INTEGER_CST || TREE_CODE (TYPE_MAX_VALUE (d1)) != INTEGER_CST)); d2_variable = (! d2_zero && (TREE_CODE (TYPE_MIN_VALUE (d2)) != INTEGER_CST || TREE_CODE (TYPE_MAX_VALUE (d2)) != INTEGER_CST)); if (d1_variable || d2_variable) break; if (d1_zero && d2_zero) break; if (d1_zero || d2_zero || ! tree_int_cst_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2)) || ! tree_int_cst_equal (TYPE_MAX_VALUE (d1), TYPE_MAX_VALUE (d2))) val = 0; break; } case RECORD_TYPE: if (flag_objc && objc_comptypes (t1, t2, 0) == 1) val = 1; break; default: break; } return attrval == 2 && val == 1 ? 2 : val; } /* Return 1 if TTL and TTR are pointers to types that are equivalent, ignoring their qualifiers. REFLEXIVE is only used by ObjC - set it to 1 or 0 depending if the check of the pointer types is meant to be reflexive or not (typically, assignments are not reflexive, while comparisons are reflexive). */ static int comp_target_types (ttl, ttr, reflexive) tree ttl, ttr; int reflexive; { int val; /* Give objc_comptypes a crack at letting these types through. */ if ((val = objc_comptypes (ttl, ttr, reflexive)) >= 0) return val; val = comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (ttl)), TYPE_MAIN_VARIANT (TREE_TYPE (ttr))); if (val == 2 && pedantic) pedwarn ("types are not quite compatible"); return val; } /* Subroutines of `comptypes'. */ /* Return 1 if two function types F1 and F2 are compatible. If either type specifies no argument types, the other must specify a fixed number of self-promoting arg types. Otherwise, if one type specifies only the number of arguments, the other must specify that number of self-promoting arg types. Otherwise, the argument types must match. */ static int function_types_compatible_p (f1, f2) tree f1, f2; { tree args1, args2; /* 1 if no need for warning yet, 2 if warning cause has been seen. */ int val = 1; int val1; if (!(TREE_TYPE (f1) == TREE_TYPE (f2) || (val = comptypes (TREE_TYPE (f1), TREE_TYPE (f2))))) return 0; args1 = TYPE_ARG_TYPES (f1); args2 = TYPE_ARG_TYPES (f2); /* An unspecified parmlist matches any specified parmlist whose argument types don't need default promotions. */ if (args1 == 0) { if (!self_promoting_args_p (args2)) return 0; /* If one of these types comes from a non-prototype fn definition, compare that with the other type's arglist. If they don't match, ask for a warning (but no error). */ if (TYPE_ACTUAL_ARG_TYPES (f1) && 1 != type_lists_compatible_p (args2, TYPE_ACTUAL_ARG_TYPES (f1))) val = 2; return val; } if (args2 == 0) { if (!self_promoting_args_p (args1)) return 0; if (TYPE_ACTUAL_ARG_TYPES (f2) && 1 != type_lists_compatible_p (args1, TYPE_ACTUAL_ARG_TYPES (f2))) val = 2; return val; } /* Both types have argument lists: compare them and propagate results. */ val1 = type_lists_compatible_p (args1, args2); return val1 != 1 ? val1 : val; } /* Check two lists of types for compatibility, returning 0 for incompatible, 1 for compatible, or 2 for compatible with warning. */ static int type_lists_compatible_p (args1, args2) tree args1, args2; { /* 1 if no need for warning yet, 2 if warning cause has been seen. */ int val = 1; int newval = 0; while (1) { if (args1 == 0 && args2 == 0) return val; /* If one list is shorter than the other, they fail to match. */ if (args1 == 0 || args2 == 0) return 0; /* A null pointer instead of a type means there is supposed to be an argument but nothing is specified about what type it has. So match anything that self-promotes. */ if (TREE_VALUE (args1) == 0) { if (c_type_promotes_to (TREE_VALUE (args2)) != TREE_VALUE (args2)) return 0; } else if (TREE_VALUE (args2) == 0) { if (c_type_promotes_to (TREE_VALUE (args1)) != TREE_VALUE (args1)) return 0; } else if (! (newval = comptypes (TYPE_MAIN_VARIANT (TREE_VALUE (args1)), TYPE_MAIN_VARIANT (TREE_VALUE (args2))))) { /* Allow wait (union {union wait *u; int *i} *) and wait (union wait *) to be compatible. */ if (TREE_CODE (TREE_VALUE (args1)) == UNION_TYPE && (TYPE_NAME (TREE_VALUE (args1)) == 0 || TYPE_TRANSPARENT_UNION (TREE_VALUE (args1))) && TREE_CODE (TYPE_SIZE (TREE_VALUE (args1))) == INTEGER_CST && tree_int_cst_equal (TYPE_SIZE (TREE_VALUE (args1)), TYPE_SIZE (TREE_VALUE (args2)))) { tree memb; for (memb = TYPE_FIELDS (TREE_VALUE (args1)); memb; memb = TREE_CHAIN (memb)) if (comptypes (TREE_TYPE (memb), TREE_VALUE (args2))) break; if (memb == 0) return 0; } else if (TREE_CODE (TREE_VALUE (args2)) == UNION_TYPE && (TYPE_NAME (TREE_VALUE (args2)) == 0 || TYPE_TRANSPARENT_UNION (TREE_VALUE (args2))) && TREE_CODE (TYPE_SIZE (TREE_VALUE (args2))) == INTEGER_CST && tree_int_cst_equal (TYPE_SIZE (TREE_VALUE (args2)), TYPE_SIZE (TREE_VALUE (args1)))) { tree memb; for (memb = TYPE_FIELDS (TREE_VALUE (args2)); memb; memb = TREE_CHAIN (memb)) if (comptypes (TREE_TYPE (memb), TREE_VALUE (args1))) break; if (memb == 0) return 0; } else return 0; } /* comptypes said ok, but record if it said to warn. */ if (newval > val) val = newval; args1 = TREE_CHAIN (args1); args2 = TREE_CHAIN (args2); } } /* Compute the size to increment a pointer by. */ tree c_size_in_bytes (type) tree type; { enum tree_code code = TREE_CODE (type); if (code == FUNCTION_TYPE || code == VOID_TYPE || code == ERROR_MARK) return size_one_node; if (!COMPLETE_OR_VOID_TYPE_P (type)) { error ("arithmetic on pointer to an incomplete type"); return size_one_node; } /* Convert in case a char is more than one unit. */ return size_binop (CEIL_DIV_EXPR, TYPE_SIZE_UNIT (type), size_int (TYPE_PRECISION (char_type_node) / BITS_PER_UNIT)); } /* Return either DECL or its known constant value (if it has one). */ tree decl_constant_value (decl) tree decl; { if (/* Don't change a variable array bound or initial value to a constant in a place where a variable is invalid. */ current_function_decl != 0 && ! TREE_THIS_VOLATILE (decl) && TREE_READONLY (decl) && DECL_INITIAL (decl) != 0 && TREE_CODE (DECL_INITIAL (decl)) != ERROR_MARK /* This is invalid if initial value is not constant. If it has either a function call, a memory reference, or a variable, then re-evaluating it could give different results. */ && TREE_CONSTANT (DECL_INITIAL (decl)) /* Check for cases where this is sub-optimal, even though valid. */ && TREE_CODE (DECL_INITIAL (decl)) != CONSTRUCTOR) return DECL_INITIAL (decl); return decl; } /* Return either DECL or its known constant value (if it has one), but return DECL if pedantic or DECL has mode BLKmode. This is for bug-compatibility with the old behavior of decl_constant_value (before GCC 3.0); every use of this function is a bug and it should be removed before GCC 3.1. It is not appropriate to use pedantic in a way that affects optimization, and BLKmode is probably not the right test for avoiding misoptimizations either. */ static tree decl_constant_value_for_broken_optimization (decl) tree decl; { if (pedantic || DECL_MODE (decl) == BLKmode) return decl; else return decl_constant_value (decl); } /* Perform the default conversion of arrays and functions to pointers. Return the result of converting EXP. For any other expression, just return EXP. */ static tree default_function_array_conversion (exp) tree exp; { tree orig_exp; tree type = TREE_TYPE (exp); enum tree_code code = TREE_CODE (type); int not_lvalue = 0; /* Strip NON_LVALUE_EXPRs and no-op conversions, since we aren't using as an lvalue. Do not use STRIP_NOPS here! It will remove conversions from pointer to integer and cause infinite recursion. */ orig_exp = exp; while (TREE_CODE (exp) == NON_LVALUE_EXPR || (TREE_CODE (exp) == NOP_EXPR && TREE_TYPE (TREE_OPERAND (exp, 0)) == TREE_TYPE (exp))) { if (TREE_CODE (exp) == NON_LVALUE_EXPR) not_lvalue = 1; exp = TREE_OPERAND (exp, 0); } /* Preserve the original expression code. */ if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (TREE_CODE (exp)))) C_SET_EXP_ORIGINAL_CODE (exp, C_EXP_ORIGINAL_CODE (orig_exp)); if (code == FUNCTION_TYPE) { return build_unary_op (ADDR_EXPR, exp, 0); } if (code == ARRAY_TYPE) { tree adr; tree restype = TREE_TYPE (type); tree ptrtype; int constp = 0; int volatilep = 0; int lvalue_array_p; if (TREE_CODE_CLASS (TREE_CODE (exp)) == 'r' || DECL_P (exp)) { constp = TREE_READONLY (exp); volatilep = TREE_THIS_VOLATILE (exp); } if (TYPE_QUALS (type) || constp || volatilep) restype = c_build_qualified_type (restype, TYPE_QUALS (type) | (constp * TYPE_QUAL_CONST) | (volatilep * TYPE_QUAL_VOLATILE)); if (TREE_CODE (exp) == INDIRECT_REF) return convert (TYPE_POINTER_TO (restype), TREE_OPERAND (exp, 0)); if (TREE_CODE (exp) == COMPOUND_EXPR) { tree op1 = default_conversion (TREE_OPERAND (exp, 1)); return build (COMPOUND_EXPR, TREE_TYPE (op1), TREE_OPERAND (exp, 0), op1); } lvalue_array_p = !not_lvalue && lvalue_p (exp); if (!flag_isoc99 && !lvalue_array_p) { /* Before C99, non-lvalue arrays do not decay to pointers. Normally, using such an array would be invalid; but it can be used correctly inside sizeof or as a statement expression. Thus, do not give an error here; an error will result later. */ return exp; } ptrtype = build_pointer_type (restype); if (TREE_CODE (exp) == VAR_DECL) { /* ??? This is not really quite correct in that the type of the operand of ADDR_EXPR is not the target type of the type of the ADDR_EXPR itself. Question is, can this lossage be avoided? */ adr = build1 (ADDR_EXPR, ptrtype, exp); if (!c_mark_addressable (exp)) return error_mark_node; TREE_CONSTANT (adr) = staticp (exp); TREE_SIDE_EFFECTS (adr) = 0; /* Default would be, same as EXP. */ return adr; } /* This way is better for a COMPONENT_REF since it can simplify the offset for a component. */ adr = build_unary_op (ADDR_EXPR, exp, 1); return convert (ptrtype, adr); } return exp; } /* Perform default promotions for C data used in expressions. Arrays and functions are converted to pointers; enumeral types or short or char, to int. In addition, manifest constants symbols are replaced by their values. */ tree default_conversion (exp) tree exp; { tree orig_exp; tree type = TREE_TYPE (exp); enum tree_code code = TREE_CODE (type); if (code == FUNCTION_TYPE || code == ARRAY_TYPE) return default_function_array_conversion (exp); /* Constants can be used directly unless they're not loadable. */ if (TREE_CODE (exp) == CONST_DECL) exp = DECL_INITIAL (exp); /* Replace a nonvolatile const static variable with its value unless it is an array, in which case we must be sure that taking the address of the array produces consistent results. */ else if (optimize && TREE_CODE (exp) == VAR_DECL && code != ARRAY_TYPE) { exp = decl_constant_value_for_broken_optimization (exp); type = TREE_TYPE (exp); } /* Strip NON_LVALUE_EXPRs and no-op conversions, since we aren't using as an lvalue. Do not use STRIP_NOPS here! It will remove conversions from pointer to integer and cause infinite recursion. */ orig_exp = exp; while (TREE_CODE (exp) == NON_LVALUE_EXPR || (TREE_CODE (exp) == NOP_EXPR && TREE_TYPE (TREE_OPERAND (exp, 0)) == TREE_TYPE (exp))) exp = TREE_OPERAND (exp, 0); /* Preserve the original expression code. */ if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (TREE_CODE (exp)))) C_SET_EXP_ORIGINAL_CODE (exp, C_EXP_ORIGINAL_CODE (orig_exp)); /* Normally convert enums to int, but convert wide enums to something wider. */ if (code == ENUMERAL_TYPE) { type = c_common_type_for_size (MAX (TYPE_PRECISION (type), TYPE_PRECISION (integer_type_node)), ((TYPE_PRECISION (type) >= TYPE_PRECISION (integer_type_node)) && TREE_UNSIGNED (type))); return convert (type, exp); } if (TREE_CODE (exp) == COMPONENT_REF && DECL_C_BIT_FIELD (TREE_OPERAND (exp, 1)) /* If it's thinner than an int, promote it like a c_promoting_integer_type_p, otherwise leave it alone. */ && 0 > compare_tree_int (DECL_SIZE (TREE_OPERAND (exp, 1)), TYPE_PRECISION (integer_type_node))) return convert (integer_type_node, exp); if (c_promoting_integer_type_p (type)) { /* Preserve unsignedness if not really getting any wider. */ if (TREE_UNSIGNED (type) && TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node)) return convert (unsigned_type_node, exp); return convert (integer_type_node, exp); } if (code == VOID_TYPE) { error ("void value not ignored as it ought to be"); return error_mark_node; } return exp; } /* Look up COMPONENT in a structure or union DECL. If the component name is not found, returns NULL_TREE. Otherwise, the return value is a TREE_LIST, with each TREE_VALUE a FIELD_DECL stepping down the chain to the component, which is in the last TREE_VALUE of the list. Normally the list is of length one, but if the component is embedded within (nested) anonymous structures or unions, the list steps down the chain to the component. */ static tree lookup_field (decl, component) tree decl, component; { tree type = TREE_TYPE (decl); tree field; /* If TYPE_LANG_SPECIFIC is set, then it is a sorted array of pointers to the field elements. Use a binary search on this array to quickly find the element. Otherwise, do a linear search. TYPE_LANG_SPECIFIC will always be set for structures which have many elements. */ if (TYPE_LANG_SPECIFIC (type)) { int bot, top, half; tree *field_array = &TYPE_LANG_SPECIFIC (type)->elts[0]; field = TYPE_FIELDS (type); bot = 0; top = TYPE_LANG_SPECIFIC (type)->len; while (top - bot > 1) { half = (top - bot + 1) >> 1; field = field_array[bot+half]; if (DECL_NAME (field) == NULL_TREE) { /* Step through all anon unions in linear fashion. */ while (DECL_NAME (field_array[bot]) == NULL_TREE) { field = field_array[bot++]; if (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE) { tree anon = lookup_field (field, component); if (anon) return tree_cons (NULL_TREE, field, anon); } } /* Entire record is only anon unions. */ if (bot > top) return NULL_TREE; /* Restart the binary search, with new lower bound. */ continue; } if (DECL_NAME (field) == component) break; if (DECL_NAME (field) < component) bot += half; else top = bot + half; } if (DECL_NAME (field_array[bot]) == component) field = field_array[bot]; else if (DECL_NAME (field) != component) return NULL_TREE; } else { for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field)) { if (DECL_NAME (field) == NULL_TREE && (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE)) { tree anon = lookup_field (field, component); if (anon) return tree_cons (NULL_TREE, field, anon); } if (DECL_NAME (field) == component) break; } if (field == NULL_TREE) return NULL_TREE; } return tree_cons (NULL_TREE, field, NULL_TREE); } /* Make an expression to refer to the COMPONENT field of structure or union value DATUM. COMPONENT is an IDENTIFIER_NODE. */ tree build_component_ref (datum, component) tree datum, component; { tree type = TREE_TYPE (datum); enum tree_code code = TREE_CODE (type); tree field = NULL; tree ref; /* If DATUM is a COMPOUND_EXPR, move our reference inside it. If pedantic ensure that the arguments are not lvalues; otherwise, if the component is an array, it would wrongly decay to a pointer in C89 mode. We cannot do this with a COND_EXPR, because in a conditional expression the default promotions are applied to both sides, and this would yield the wrong type of the result; for example, if the components have type "char". */ switch (TREE_CODE (datum)) { case COMPOUND_EXPR: { tree value = build_component_ref (TREE_OPERAND (datum, 1), component); return build (COMPOUND_EXPR, TREE_TYPE (value), TREE_OPERAND (datum, 0), pedantic_non_lvalue (value)); } default: break; } /* See if there is a field or component with name COMPONENT. */ if (code == RECORD_TYPE || code == UNION_TYPE) { if (!COMPLETE_TYPE_P (type)) { c_incomplete_type_error (NULL_TREE, type); return error_mark_node; } field = lookup_field (datum, component); if (!field) { error ("%s has no member named `%s'", code == RECORD_TYPE ? "structure" : "union", IDENTIFIER_POINTER (component)); return error_mark_node; } /* Chain the COMPONENT_REFs if necessary down to the FIELD. This might be better solved in future the way the C++ front end does it - by giving the anonymous entities each a separate name and type, and then have build_component_ref recursively call itself. We can't do that here. */ for (; field; field = TREE_CHAIN (field)) { tree subdatum = TREE_VALUE (field); if (TREE_TYPE (subdatum) == error_mark_node) return error_mark_node; ref = build (COMPONENT_REF, TREE_TYPE (subdatum), datum, subdatum); if (TREE_READONLY (datum) || TREE_READONLY (subdatum)) TREE_READONLY (ref) = 1; if (TREE_THIS_VOLATILE (datum) || TREE_THIS_VOLATILE (subdatum)) TREE_THIS_VOLATILE (ref) = 1; if (TREE_DEPRECATED (subdatum)) warn_deprecated_use (subdatum); datum = ref; } return ref; } else if (code != ERROR_MARK) error ("request for member `%s' in something not a structure or union", IDENTIFIER_POINTER (component)); return error_mark_node; } /* Given an expression PTR for a pointer, return an expression for the value pointed to. ERRORSTRING is the name of the operator to appear in error messages. */ tree build_indirect_ref (ptr, errorstring) tree ptr; const char *errorstring; { tree pointer = default_conversion (ptr); tree type = TREE_TYPE (pointer); if (TREE_CODE (type) == POINTER_TYPE) { if (TREE_CODE (pointer) == ADDR_EXPR && !flag_volatile && (TREE_TYPE (TREE_OPERAND (pointer, 0)) == TREE_TYPE (type))) return TREE_OPERAND (pointer, 0); else { tree t = TREE_TYPE (type); tree ref = build1 (INDIRECT_REF, TYPE_MAIN_VARIANT (t), pointer); if (!COMPLETE_OR_VOID_TYPE_P (t) && TREE_CODE (t) != ARRAY_TYPE) { error ("dereferencing pointer to incomplete type"); return error_mark_node; } if (VOID_TYPE_P (t) && skip_evaluation == 0) warning ("dereferencing `void *' pointer"); /* We *must* set TREE_READONLY when dereferencing a pointer to const, so that we get the proper error message if the result is used to assign to. Also, &* is supposed to be a no-op. And ANSI C seems to specify that the type of the result should be the const type. */ /* A de-reference of a pointer to const is not a const. It is valid to change it via some other pointer. */ TREE_READONLY (ref) = TYPE_READONLY (t); TREE_SIDE_EFFECTS (ref) = TYPE_VOLATILE (t) || TREE_SIDE_EFFECTS (pointer) || flag_volatile; TREE_THIS_VOLATILE (ref) = TYPE_VOLATILE (t); return ref; } } else if (TREE_CODE (pointer) != ERROR_MARK) error ("invalid type argument of `%s'", errorstring); return error_mark_node; } /* This handles expressions of the form "a[i]", which denotes an array reference. This is logically equivalent in C to *(a+i), but we may do it differently. If A is a variable or a member, we generate a primitive ARRAY_REF. This avoids forcing the array out of registers, and can work on arrays that are not lvalues (for example, members of structures returned by functions). */ tree build_array_ref (array, index) tree array, index; { if (index == 0) { error ("subscript missing in array reference"); return error_mark_node; } if (TREE_TYPE (array) == error_mark_node || TREE_TYPE (index) == error_mark_node) return error_mark_node; if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE && TREE_CODE (array) != INDIRECT_REF) { tree rval, type; /* Subscripting with type char is likely to lose on a machine where chars are signed. So warn on any machine, but optionally. Don't warn for unsigned char since that type is safe. Don't warn for signed char because anyone who uses that must have done so deliberately. */ if (warn_char_subscripts && TYPE_MAIN_VARIANT (TREE_TYPE (index)) == char_type_node) warning ("array subscript has type `char'"); /* Apply default promotions *after* noticing character types. */ index = default_conversion (index); /* Require integer *after* promotion, for sake of enums. */ if (TREE_CODE (TREE_TYPE (index)) != INTEGER_TYPE) { error ("array subscript is not an integer"); return error_mark_node; } /* An array that is indexed by a non-constant cannot be stored in a register; we must be able to do address arithmetic on its address. Likewise an array of elements of variable size. */ if (TREE_CODE (index) != INTEGER_CST || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array))) && TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array)))) != INTEGER_CST)) { if (!c_mark_addressable (array)) return error_mark_node; } /* An array that is indexed by a constant value which is not within the array bounds cannot be stored in a register either; because we would get a crash in store_bit_field/extract_bit_field when trying to access a non-existent part of the register. */ if (TREE_CODE (index) == INTEGER_CST && TYPE_VALUES (TREE_TYPE (array)) && ! int_fits_type_p (index, TYPE_VALUES (TREE_TYPE (array)))) { if (!c_mark_addressable (array)) return error_mark_node; } if (pedantic) { tree foo = array; while (TREE_CODE (foo) == COMPONENT_REF) foo = TREE_OPERAND (foo, 0); if (TREE_CODE (foo) == VAR_DECL && DECL_REGISTER (foo)) pedwarn ("ISO C forbids subscripting `register' array"); else if (! flag_isoc99 && ! lvalue_p (foo)) pedwarn ("ISO C90 forbids subscripting non-lvalue array"); } type = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (array))); rval = build (ARRAY_REF, type, array, index); /* Array ref is const/volatile if the array elements are or if the array is. */ TREE_READONLY (rval) |= (TYPE_READONLY (TREE_TYPE (TREE_TYPE (array))) | TREE_READONLY (array)); TREE_SIDE_EFFECTS (rval) |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array))) | TREE_SIDE_EFFECTS (array)); TREE_THIS_VOLATILE (rval) |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array))) /* This was added by rms on 16 Nov 91. It fixes vol struct foo *a; a->elts[1] in an inline function. Hope it doesn't break something else. */ | TREE_THIS_VOLATILE (array)); return require_complete_type (fold (rval)); } { tree ar = default_conversion (array); tree ind = default_conversion (index); /* Do the same warning check as above, but only on the part that's syntactically the index and only if it is also semantically the index. */ if (warn_char_subscripts && TREE_CODE (TREE_TYPE (index)) == INTEGER_TYPE && TYPE_MAIN_VARIANT (TREE_TYPE (index)) == char_type_node) warning ("subscript has type `char'"); /* Put the integer in IND to simplify error checking. */ if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE) { tree temp = ar; ar = ind; ind = temp; } if (ar == error_mark_node) return ar; if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE || TREE_CODE (TREE_TYPE (TREE_TYPE (ar))) == FUNCTION_TYPE) { error ("subscripted value is neither array nor pointer"); return error_mark_node; } if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE) { error ("array subscript is not an integer"); return error_mark_node; } return build_indirect_ref (build_binary_op (PLUS_EXPR, ar, ind, 0), "array indexing"); } } /* Build an external reference to identifier ID. FUN indicates whether this will be used for a function call. */ tree build_external_ref (id, fun) tree id; int fun; { tree ref; tree decl = lookup_name (id); tree objc_ivar = lookup_objc_ivar (id); if (decl && TREE_DEPRECATED (decl)) warn_deprecated_use (decl); if (!decl || decl == error_mark_node || C_DECL_ANTICIPATED (decl)) { if (objc_ivar) ref = objc_ivar; else if (fun) { if (!decl || decl == error_mark_node) /* Ordinary implicit function declaration. */ ref = implicitly_declare (id); else { /* Implicit declaration of built-in function. Don't change the built-in declaration, but don't let this go by silently, either. */ implicit_decl_warning (id); /* only issue this warning once */ C_DECL_ANTICIPATED (decl) = 0; ref = decl; } } else { /* Reference to undeclared variable, including reference to builtin outside of function-call context. */ if (current_function_decl == 0) error ("`%s' undeclared here (not in a function)", IDENTIFIER_POINTER (id)); else { if (IDENTIFIER_GLOBAL_VALUE (id) != error_mark_node || IDENTIFIER_ERROR_LOCUS (id) != current_function_decl) { error ("`%s' undeclared (first use in this function)", IDENTIFIER_POINTER (id)); if (! undeclared_variable_notice) { error ("(Each undeclared identifier is reported only once"); error ("for each function it appears in.)"); undeclared_variable_notice = 1; } } IDENTIFIER_GLOBAL_VALUE (id) = error_mark_node; IDENTIFIER_ERROR_LOCUS (id) = current_function_decl; } return error_mark_node; } } else { /* Properly declared variable or function reference. */ if (!objc_ivar) ref = decl; else if (decl != objc_ivar && IDENTIFIER_LOCAL_VALUE (id)) { warning ("local declaration of `%s' hides instance variable", IDENTIFIER_POINTER (id)); ref = decl; } else ref = objc_ivar; } if (TREE_TYPE (ref) == error_mark_node) return error_mark_node; if (!skip_evaluation) assemble_external (ref); TREE_USED (ref) = 1; if (TREE_CODE (ref) == CONST_DECL) { ref = DECL_INITIAL (ref); TREE_CONSTANT (ref) = 1; } return ref; } /* Build a function call to function FUNCTION with parameters PARAMS. PARAMS is a list--a chain of TREE_LIST nodes--in which the TREE_VALUE of each node is a parameter-expression. FUNCTION's data type may be a function type or a pointer-to-function. */ tree build_function_call (function, params) tree function, params; { tree fntype, fundecl = 0; tree coerced_params; tree name = NULL_TREE, assembler_name = NULL_TREE, result; /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */ STRIP_TYPE_NOPS (function); /* Convert anything with function type to a pointer-to-function. */ if (TREE_CODE (function) == FUNCTION_DECL) { name = DECL_NAME (function); assembler_name = DECL_ASSEMBLER_NAME (function); /* Differs from default_conversion by not setting TREE_ADDRESSABLE (because calling an inline function does not mean the function needs to be separately compiled). */ fntype = build_type_variant (TREE_TYPE (function), TREE_READONLY (function), TREE_THIS_VOLATILE (function)); fundecl = function; function = build1 (ADDR_EXPR, build_pointer_type (fntype), function); } else function = default_conversion (function); fntype = TREE_TYPE (function); if (TREE_CODE (fntype) == ERROR_MARK) return error_mark_node; if (!(TREE_CODE (fntype) == POINTER_TYPE && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE)) { error ("called object is not a function"); return error_mark_node; } if (fundecl && TREE_THIS_VOLATILE (fundecl)) current_function_returns_abnormally = 1; /* fntype now gets the type of function pointed to. */ fntype = TREE_TYPE (fntype); /* Convert the parameters to the types declared in the function prototype, or apply default promotions. */ coerced_params = convert_arguments (TYPE_ARG_TYPES (fntype), params, name, fundecl); /* Check that the arguments to the function are valid. */ check_function_arguments (TYPE_ATTRIBUTES (fntype), coerced_params); /* Recognize certain built-in functions so we can make tree-codes other than CALL_EXPR. We do this when it enables fold-const.c to do something useful. */ if (TREE_CODE (function) == ADDR_EXPR && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL && DECL_BUILT_IN (TREE_OPERAND (function, 0))) { result = expand_tree_builtin (TREE_OPERAND (function, 0), params, coerced_params); if (result) return result; } result = build (CALL_EXPR, TREE_TYPE (fntype), function, coerced_params, NULL_TREE); TREE_SIDE_EFFECTS (result) = 1; result = fold (result); if (VOID_TYPE_P (TREE_TYPE (result))) return result; return require_complete_type (result); } /* Convert the argument expressions in the list VALUES to the types in the list TYPELIST. The result is a list of converted argument expressions. If TYPELIST is exhausted, or when an element has NULL as its type, perform the default conversions. PARMLIST is the chain of parm decls for the function being called. It may be 0, if that info is not available. It is used only for generating error messages. NAME is an IDENTIFIER_NODE or 0. It is used only for error messages. This is also where warnings about wrong number of args are generated. Both VALUES and the returned value are chains of TREE_LIST nodes with the elements of the list in the TREE_VALUE slots of those nodes. */ static tree convert_arguments (typelist, values, name, fundecl) tree typelist, values, name, fundecl; { tree typetail, valtail; tree result = NULL; int parmnum; /* Scan the given expressions and types, producing individual converted arguments and pushing them on RESULT in reverse order. */ for (valtail = values, typetail = typelist, parmnum = 0; valtail; valtail = TREE_CHAIN (valtail), parmnum++) { tree type = typetail ? TREE_VALUE (typetail) : 0; tree val = TREE_VALUE (valtail); if (type == void_type_node) { if (name) error ("too many arguments to function `%s'", IDENTIFIER_POINTER (name)); else error ("too many arguments to function"); break; } /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */ /* Do not use STRIP_NOPS here! We do not want an enumerator with value 0 to convert automatically to a pointer. */ if (TREE_CODE (val) == NON_LVALUE_EXPR) val = TREE_OPERAND (val, 0); val = default_function_array_conversion (val); val = require_complete_type (val); if (type != 0) { /* Formal parm type is specified by a function prototype. */ tree parmval; if (!COMPLETE_TYPE_P (type)) { error ("type of formal parameter %d is incomplete", parmnum + 1); parmval = val; } else { /* Optionally warn about conversions that differ from the default conversions. */ if (warn_conversion || warn_traditional) { int formal_prec = TYPE_PRECISION (type); if (INTEGRAL_TYPE_P (type) && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE) warn_for_assignment ("%s as integer rather than floating due to prototype", (char *) 0, name, parmnum + 1); if (INTEGRAL_TYPE_P (type) && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE) warn_for_assignment ("%s as integer rather than complex due to prototype", (char *) 0, name, parmnum + 1); else if (TREE_CODE (type) == COMPLEX_TYPE && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE) warn_for_assignment ("%s as complex rather than floating due to prototype", (char *) 0, name, parmnum + 1); else if (TREE_CODE (type) == REAL_TYPE && INTEGRAL_TYPE_P (TREE_TYPE (val))) warn_for_assignment ("%s as floating rather than integer due to prototype", (char *) 0, name, parmnum + 1); else if (TREE_CODE (type) == COMPLEX_TYPE && INTEGRAL_TYPE_P (TREE_TYPE (val))) warn_for_assignment ("%s as complex rather than integer due to prototype", (char *) 0, name, parmnum + 1); else if (TREE_CODE (type) == REAL_TYPE && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE) warn_for_assignment ("%s as floating rather than complex due to prototype", (char *) 0, name, parmnum + 1); /* ??? At some point, messages should be written about conversions between complex types, but that's too messy to do now. */ else if (TREE_CODE (type) == REAL_TYPE && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE) { /* Warn if any argument is passed as `float', since without a prototype it would be `double'. */ if (formal_prec == TYPE_PRECISION (float_type_node)) warn_for_assignment ("%s as `float' rather than `double' due to prototype", (char *) 0, name, parmnum + 1); } /* Detect integer changing in width or signedness. These warnings are only activated with -Wconversion, not with -Wtraditional. */ else if (warn_conversion && INTEGRAL_TYPE_P (type) && INTEGRAL_TYPE_P (TREE_TYPE (val))) { tree would_have_been = default_conversion (val); tree type1 = TREE_TYPE (would_have_been); if (TREE_CODE (type) == ENUMERAL_TYPE && (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (TREE_TYPE (val)))) /* No warning if function asks for enum and the actual arg is that enum type. */ ; else if (formal_prec != TYPE_PRECISION (type1)) warn_for_assignment ("%s with different width due to prototype", (char *) 0, name, parmnum + 1); else if (TREE_UNSIGNED (type) == TREE_UNSIGNED (type1)) ; /* Don't complain if the formal parameter type is an enum, because we can't tell now whether the value was an enum--even the same enum. */ else if (TREE_CODE (type) == ENUMERAL_TYPE) ; else if (TREE_CODE (val) == INTEGER_CST && int_fits_type_p (val, type)) /* Change in signedness doesn't matter if a constant value is unaffected. */ ; /* Likewise for a constant in a NOP_EXPR. */ else if (TREE_CODE (val) == NOP_EXPR && TREE_CODE (TREE_OPERAND (val, 0)) == INTEGER_CST && int_fits_type_p (TREE_OPERAND (val, 0), type)) ; #if 0 /* We never get such tree structure here. */ else if (TREE_CODE (TREE_TYPE (val)) == ENUMERAL_TYPE && int_fits_type_p (TYPE_MIN_VALUE (TREE_TYPE (val)), type) && int_fits_type_p (TYPE_MAX_VALUE (TREE_TYPE (val)), type)) /* Change in signedness doesn't matter if an enum value is unaffected. */ ; #endif /* If the value is extended from a narrower unsigned type, it doesn't matter whether we pass it as signed or unsigned; the value certainly is the same either way. */ else if (TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type) && TREE_UNSIGNED (TREE_TYPE (val))) ; else if (TREE_UNSIGNED (type)) warn_for_assignment ("%s as unsigned due to prototype", (char *) 0, name, parmnum + 1); else warn_for_assignment ("%s as signed due to prototype", (char *) 0, name, parmnum + 1); } } parmval = convert_for_assignment (type, val, (char *) 0, /* arg passing */ fundecl, name, parmnum + 1); if (PROMOTE_PROTOTYPES && INTEGRAL_TYPE_P (type) && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))) parmval = default_conversion (parmval); } result = tree_cons (NULL_TREE, parmval, result); } else if (TREE_CODE (TREE_TYPE (val)) == REAL_TYPE && (TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (double_type_node))) /* Convert `float' to `double'. */ result = tree_cons (NULL_TREE, convert (double_type_node, val), result); else /* Convert `short' and `char' to full-size `int'. */ result = tree_cons (NULL_TREE, default_conversion (val), result); if (typetail) typetail = TREE_CHAIN (typetail); } if (typetail != 0 && TREE_VALUE (typetail) != void_type_node) { if (name) error ("too few arguments to function `%s'", IDENTIFIER_POINTER (name)); else error ("too few arguments to function"); } return nreverse (result); } /* This is the entry point used by the parser for binary operators in the input. In addition to constructing the expression, we check for operands that were written with other binary operators in a way that is likely to confuse the user. */ tree parser_build_binary_op (code, arg1, arg2) enum tree_code code; tree arg1, arg2; { tree result = build_binary_op (code, arg1, arg2, 1); char class; char class1 = TREE_CODE_CLASS (TREE_CODE (arg1)); char class2 = TREE_CODE_CLASS (TREE_CODE (arg2)); enum tree_code code1 = ERROR_MARK; enum tree_code code2 = ERROR_MARK; if (TREE_CODE (result) == ERROR_MARK) return error_mark_node; if (IS_EXPR_CODE_CLASS (class1)) code1 = C_EXP_ORIGINAL_CODE (arg1); if (IS_EXPR_CODE_CLASS (class2)) code2 = C_EXP_ORIGINAL_CODE (arg2); /* Check for cases such as x+y<= 0) warning ("right shift count >= width of type"); } } /* Use the type of the value to be shifted. */ result_type = type0; /* Convert the shift-count to an integer, regardless of size of value being shifted. */ if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node) op1 = convert (integer_type_node, op1); /* Avoid converting op1 to result_type later. */ converted = 1; } break; case LSHIFT_EXPR: if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) { if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0) { if (tree_int_cst_sgn (op1) < 0) warning ("left shift count is negative"); else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0) warning ("left shift count >= width of type"); } /* Use the type of the value to be shifted. */ result_type = type0; /* Convert the shift-count to an integer, regardless of size of value being shifted. */ if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node) op1 = convert (integer_type_node, op1); /* Avoid converting op1 to result_type later. */ converted = 1; } break; case RROTATE_EXPR: case LROTATE_EXPR: if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) { if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0) { if (tree_int_cst_sgn (op1) < 0) warning ("shift count is negative"); else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0) warning ("shift count >= width of type"); } /* Use the type of the value to be shifted. */ result_type = type0; /* Convert the shift-count to an integer, regardless of size of value being shifted. */ if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node) op1 = convert (integer_type_node, op1); /* Avoid converting op1 to result_type later. */ converted = 1; } break; case EQ_EXPR: case NE_EXPR: if (warn_float_equal && (code0 == REAL_TYPE || code1 == REAL_TYPE)) warning ("comparing floating point with == or != is unsafe"); /* Result of comparison is always int, but don't convert the args to int! */ build_type = integer_type_node; if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE) && (code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE)) short_compare = 1; else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE) { tree tt0 = TREE_TYPE (type0); tree tt1 = TREE_TYPE (type1); /* Anything compares with void *. void * compares with anything. Otherwise, the targets must be compatible and both must be object or both incomplete. */ if (comp_target_types (type0, type1, 1)) result_type = common_type (type0, type1); else if (VOID_TYPE_P (tt0)) { /* op0 != orig_op0 detects the case of something whose value is 0 but which isn't a valid null ptr const. */ if (pedantic && (!integer_zerop (op0) || op0 != orig_op0) && TREE_CODE (tt1) == FUNCTION_TYPE) pedwarn ("ISO C forbids comparison of `void *' with function pointer"); } else if (VOID_TYPE_P (tt1)) { if (pedantic && (!integer_zerop (op1) || op1 != orig_op1) && TREE_CODE (tt0) == FUNCTION_TYPE) pedwarn ("ISO C forbids comparison of `void *' with function pointer"); } else pedwarn ("comparison of distinct pointer types lacks a cast"); if (result_type == NULL_TREE) result_type = ptr_type_node; } else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST && integer_zerop (op1)) result_type = type0; else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST && integer_zerop (op0)) result_type = type1; else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE) { result_type = type0; pedwarn ("comparison between pointer and integer"); } else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE) { result_type = type1; pedwarn ("comparison between pointer and integer"); } break; case MAX_EXPR: case MIN_EXPR: if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE) && (code1 == INTEGER_TYPE || code1 == REAL_TYPE)) shorten = 1; else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE) { if (comp_target_types (type0, type1, 1)) { result_type = common_type (type0, type1); if (pedantic && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE) pedwarn ("ISO C forbids ordered comparisons of pointers to functions"); } else { result_type = ptr_type_node; pedwarn ("comparison of distinct pointer types lacks a cast"); } } break; case LE_EXPR: case GE_EXPR: case LT_EXPR: case GT_EXPR: build_type = integer_type_node; if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE) && (code1 == INTEGER_TYPE || code1 == REAL_TYPE)) short_compare = 1; else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE) { if (comp_target_types (type0, type1, 1)) { result_type = common_type (type0, type1); if (!COMPLETE_TYPE_P (TREE_TYPE (type0)) != !COMPLETE_TYPE_P (TREE_TYPE (type1))) pedwarn ("comparison of complete and incomplete pointers"); else if (pedantic && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE) pedwarn ("ISO C forbids ordered comparisons of pointers to functions"); } else { result_type = ptr_type_node; pedwarn ("comparison of distinct pointer types lacks a cast"); } } else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST && integer_zerop (op1)) { result_type = type0; if (pedantic || extra_warnings) pedwarn ("ordered comparison of pointer with integer zero"); } else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST && integer_zerop (op0)) { result_type = type1; if (pedantic) pedwarn ("ordered comparison of pointer with integer zero"); } else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE) { result_type = type0; pedwarn ("comparison between pointer and integer"); } else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE) { result_type = type1; pedwarn ("comparison between pointer and integer"); } break; case UNORDERED_EXPR: case ORDERED_EXPR: case UNLT_EXPR: case UNLE_EXPR: case UNGT_EXPR: case UNGE_EXPR: case UNEQ_EXPR: build_type = integer_type_node; if (code0 != REAL_TYPE || code1 != REAL_TYPE) { error ("unordered comparison on non-floating point argument"); return error_mark_node; } common = 1; break; default: break; } if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE) && (code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE)) { int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE); if (shorten || common || short_compare) result_type = common_type (type0, type1); /* For certain operations (which identify themselves by shorten != 0) if both args were extended from the same smaller type, do the arithmetic in that type and then extend. shorten !=0 and !=1 indicates a bitwise operation. For them, this optimization is safe only if both args are zero-extended or both are sign-extended. Otherwise, we might change the result. Eg, (short)-1 | (unsigned short)-1 is (int)-1 but calculated in (unsigned short) it would be (unsigned short)-1. */ if (shorten && none_complex) { int unsigned0, unsigned1; tree arg0 = get_narrower (op0, &unsigned0); tree arg1 = get_narrower (op1, &unsigned1); /* UNS is 1 if the operation to be done is an unsigned one. */ int uns = TREE_UNSIGNED (result_type); tree type; final_type = result_type; /* Handle the case that OP0 (or OP1) does not *contain* a conversion but it *requires* conversion to FINAL_TYPE. */ if ((TYPE_PRECISION (TREE_TYPE (op0)) == TYPE_PRECISION (TREE_TYPE (arg0))) && TREE_TYPE (op0) != final_type) unsigned0 = TREE_UNSIGNED (TREE_TYPE (op0)); if ((TYPE_PRECISION (TREE_TYPE (op1)) == TYPE_PRECISION (TREE_TYPE (arg1))) && TREE_TYPE (op1) != final_type) unsigned1 = TREE_UNSIGNED (TREE_TYPE (op1)); /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */ /* For bitwise operations, signedness of nominal type does not matter. Consider only how operands were extended. */ if (shorten == -1) uns = unsigned0; /* Note that in all three cases below we refrain from optimizing an unsigned operation on sign-extended args. That would not be valid. */ /* Both args variable: if both extended in same way from same width, do it in that width. Do it unsigned if args were zero-extended. */ if ((TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)) && (TYPE_PRECISION (TREE_TYPE (arg1)) == TYPE_PRECISION (TREE_TYPE (arg0))) && unsigned0 == unsigned1 && (unsigned0 || !uns)) result_type = c_common_signed_or_unsigned_type (unsigned0, common_type (TREE_TYPE (arg0), TREE_TYPE (arg1))); else if (TREE_CODE (arg0) == INTEGER_CST && (unsigned1 || !uns) && (TYPE_PRECISION (TREE_TYPE (arg1)) < TYPE_PRECISION (result_type)) && (type = c_common_signed_or_unsigned_type (unsigned1, TREE_TYPE (arg1)), int_fits_type_p (arg0, type))) result_type = type; else if (TREE_CODE (arg1) == INTEGER_CST && (unsigned0 || !uns) && (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)) && (type = c_common_signed_or_unsigned_type (unsigned0, TREE_TYPE (arg0)), int_fits_type_p (arg1, type))) result_type = type; } /* Shifts can be shortened if shifting right. */ if (short_shift) { int unsigned_arg; tree arg0 = get_narrower (op0, &unsigned_arg); final_type = result_type; if (arg0 == op0 && final_type == TREE_TYPE (op0)) unsigned_arg = TREE_UNSIGNED (TREE_TYPE (op0)); if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type) /* We can shorten only if the shift count is less than the number of bits in the smaller type size. */ && compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0 /* We cannot drop an unsigned shift after sign-extension. */ && (!TREE_UNSIGNED (final_type) || unsigned_arg)) { /* Do an unsigned shift if the operand was zero-extended. */ result_type = c_common_signed_or_unsigned_type (unsigned_arg, TREE_TYPE (arg0)); /* Convert value-to-be-shifted to that type. */ if (TREE_TYPE (op0) != result_type) op0 = convert (result_type, op0); converted = 1; } } /* Comparison operations are shortened too but differently. They identify themselves by setting short_compare = 1. */ if (short_compare) { /* Don't write &op0, etc., because that would prevent op0 from being kept in a register. Instead, make copies of the our local variables and pass the copies by reference, then copy them back afterward. */ tree xop0 = op0, xop1 = op1, xresult_type = result_type; enum tree_code xresultcode = resultcode; tree val = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode); if (val != 0) return val; op0 = xop0, op1 = xop1; converted = 1; resultcode = xresultcode; if ((warn_sign_compare < 0 ? extra_warnings : warn_sign_compare != 0) && skip_evaluation == 0) { int op0_signed = ! TREE_UNSIGNED (TREE_TYPE (orig_op0)); int op1_signed = ! TREE_UNSIGNED (TREE_TYPE (orig_op1)); int unsignedp0, unsignedp1; tree primop0 = get_narrower (op0, &unsignedp0); tree primop1 = get_narrower (op1, &unsignedp1); xop0 = orig_op0; xop1 = orig_op1; STRIP_TYPE_NOPS (xop0); STRIP_TYPE_NOPS (xop1); /* Give warnings for comparisons between signed and unsigned quantities that may fail. Do the checking based on the original operand trees, so that casts will be considered, but default promotions won't be. Do not warn if the comparison is being done in a signed type, since the signed type will only be chosen if it can represent all the values of the unsigned type. */ if (! TREE_UNSIGNED (result_type)) /* OK */; /* Do not warn if both operands are the same signedness. */ else if (op0_signed == op1_signed) /* OK */; else { tree sop, uop; if (op0_signed) sop = xop0, uop = xop1; else sop = xop1, uop = xop0; /* Do not warn if the signed quantity is an unsuffixed integer literal (or some static constant expression involving such literals or a conditional expression involving such literals) and it is non-negative. */ if (c_tree_expr_nonnegative_p (sop)) /* OK */; /* Do not warn if the comparison is an equality operation, the unsigned quantity is an integral constant, and it would fit in the result if the result were signed. */ else if (TREE_CODE (uop) == INTEGER_CST && (resultcode == EQ_EXPR || resultcode == NE_EXPR) && int_fits_type_p (uop, c_common_signed_type (result_type))) /* OK */; /* Do not warn if the unsigned quantity is an enumeration constant and its maximum value would fit in the result if the result were signed. */ else if (TREE_CODE (uop) == INTEGER_CST && TREE_CODE (TREE_TYPE (uop)) == ENUMERAL_TYPE && int_fits_type_p (TYPE_MAX_VALUE (TREE_TYPE(uop)), c_common_signed_type (result_type))) /* OK */; else warning ("comparison between signed and unsigned"); } /* Warn if two unsigned values are being compared in a size larger than their original size, and one (and only one) is the result of a `~' operator. This comparison will always fail. Also warn if one operand is a constant, and the constant does not have all bits set that are set in the ~ operand when it is extended. */ if ((TREE_CODE (primop0) == BIT_NOT_EXPR) != (TREE_CODE (primop1) == BIT_NOT_EXPR)) { if (TREE_CODE (primop0) == BIT_NOT_EXPR) primop0 = get_narrower (TREE_OPERAND (primop0, 0), &unsignedp0); else primop1 = get_narrower (TREE_OPERAND (primop1, 0), &unsignedp1); if (host_integerp (primop0, 0) || host_integerp (primop1, 0)) { tree primop; HOST_WIDE_INT constant, mask; int unsignedp, bits; if (host_integerp (primop0, 0)) { primop = primop1; unsignedp = unsignedp1; constant = tree_low_cst (primop0, 0); } else { primop = primop0; unsignedp = unsignedp0; constant = tree_low_cst (primop1, 0); } bits = TYPE_PRECISION (TREE_TYPE (primop)); if (bits < TYPE_PRECISION (result_type) && bits < HOST_BITS_PER_WIDE_INT && unsignedp) { mask = (~ (HOST_WIDE_INT) 0) << bits; if ((mask & constant) != mask) warning ("comparison of promoted ~unsigned with constant"); } } else if (unsignedp0 && unsignedp1 && (TYPE_PRECISION (TREE_TYPE (primop0)) < TYPE_PRECISION (result_type)) && (TYPE_PRECISION (TREE_TYPE (primop1)) < TYPE_PRECISION (result_type))) warning ("comparison of promoted ~unsigned with unsigned"); } } } } /* At this point, RESULT_TYPE must be nonzero to avoid an error message. If CONVERTED is zero, both args will be converted to type RESULT_TYPE. Then the expression will be built. It will be given type FINAL_TYPE if that is nonzero; otherwise, it will be given type RESULT_TYPE. */ if (!result_type) { binary_op_error (code); return error_mark_node; } if (! converted) { if (TREE_TYPE (op0) != result_type) op0 = convert (result_type, op0); if (TREE_TYPE (op1) != result_type) op1 = convert (result_type, op1); } if (build_type == NULL_TREE) build_type = result_type; { tree result = build (resultcode, build_type, op0, op1); tree folded; folded = fold (result); if (folded == result) TREE_CONSTANT (folded) = TREE_CONSTANT (op0) & TREE_CONSTANT (op1); if (final_type != 0) return convert (final_type, folded); return folded; } } /* Return true if `t' is known to be non-negative. */ int c_tree_expr_nonnegative_p (t) tree t; { if (TREE_CODE (t) == STMT_EXPR) { t=COMPOUND_BODY (STMT_EXPR_STMT (t)); /* Find the last statement in the chain, ignoring the final * scope statement */ while (TREE_CHAIN (t) != NULL_TREE && TREE_CODE (TREE_CHAIN (t)) != SCOPE_STMT) t=TREE_CHAIN (t); return tree_expr_nonnegative_p (TREE_OPERAND (t, 0)); } return tree_expr_nonnegative_p (t); } /* Return a tree for the difference of pointers OP0 and OP1. The resulting tree has type int. */ static tree pointer_diff (op0, op1) tree op0, op1; { tree result, folded; tree restype = ptrdiff_type_node; tree target_type = TREE_TYPE (TREE_TYPE (op0)); tree con0, con1, lit0, lit1; tree orig_op1 = op1; if (pedantic || warn_pointer_arith) { if (TREE_CODE (target_type) == VOID_TYPE) pedwarn ("pointer of type `void *' used in subtraction"); if (TREE_CODE (target_type) == FUNCTION_TYPE) pedwarn ("pointer to a function used in subtraction"); } /* If the conversion to ptrdiff_type does anything like widening or converting a partial to an integral mode, we get a convert_expression that is in the way to do any simplifications. (fold-const.c doesn't know that the extra bits won't be needed. split_tree uses STRIP_SIGN_NOPS, which leaves conversions to a different mode in place.) So first try to find a common term here 'by hand'; we want to cover at least the cases that occur in legal static initializers. */ con0 = TREE_CODE (op0) == NOP_EXPR ? TREE_OPERAND (op0, 0) : op0; con1 = TREE_CODE (op1) == NOP_EXPR ? TREE_OPERAND (op1, 0) : op1; if (TREE_CODE (con0) == PLUS_EXPR) { lit0 = TREE_OPERAND (con0, 1); con0 = TREE_OPERAND (con0, 0); } else lit0 = integer_zero_node; if (TREE_CODE (con1) == PLUS_EXPR) { lit1 = TREE_OPERAND (con1, 1); con1 = TREE_OPERAND (con1, 0); } else lit1 = integer_zero_node; if (operand_equal_p (con0, con1, 0)) { op0 = lit0; op1 = lit1; } /* First do the subtraction as integers; then drop through to build the divide operator. Do not do default conversions on the minus operator in case restype is a short type. */ op0 = build_binary_op (MINUS_EXPR, convert (restype, op0), convert (restype, op1), 0); /* This generates an error if op1 is pointer to incomplete type. */ if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (TREE_TYPE (orig_op1)))) error ("arithmetic on pointer to an incomplete type"); /* This generates an error if op0 is pointer to incomplete type. */ op1 = c_size_in_bytes (target_type); /* Divide by the size, in easiest possible way. */ result = build (EXACT_DIV_EXPR, restype, op0, convert (restype, op1)); folded = fold (result); if (folded == result) TREE_CONSTANT (folded) = TREE_CONSTANT (op0) & TREE_CONSTANT (op1); return folded; } /* Construct and perhaps optimize a tree representation for a unary operation. CODE, a tree_code, specifies the operation and XARG is the operand. For any CODE other than ADDR_EXPR, FLAG nonzero suppresses the default promotions (such as from short to int). For ADDR_EXPR, the default promotions are not applied; FLAG nonzero allows non-lvalues; this is only used to handle conversion of non-lvalue arrays to pointers in C99. */ tree build_unary_op (code, xarg, flag) enum tree_code code; tree xarg; int flag; { /* No default_conversion here. It causes trouble for ADDR_EXPR. */ tree arg = xarg; tree argtype = 0; enum tree_code typecode = TREE_CODE (TREE_TYPE (arg)); tree val; int noconvert = flag; if (typecode == ERROR_MARK) return error_mark_node; if (typecode == ENUMERAL_TYPE || typecode == BOOLEAN_TYPE) typecode = INTEGER_TYPE; switch (code) { case CONVERT_EXPR: /* This is used for unary plus, because a CONVERT_EXPR is enough to prevent anybody from looking inside for associativity, but won't generate any code. */ if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE || typecode == COMPLEX_TYPE)) { error ("wrong type argument to unary plus"); return error_mark_node; } else if (!noconvert) arg = default_conversion (arg); arg = non_lvalue (arg); break; case NEGATE_EXPR: if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE || typecode == COMPLEX_TYPE || typecode == VECTOR_TYPE)) { error ("wrong type argument to unary minus"); return error_mark_node; } else if (!noconvert) arg = default_conversion (arg); break; case BIT_NOT_EXPR: if (typecode == INTEGER_TYPE || typecode == VECTOR_TYPE) { if (!noconvert) arg = default_conversion (arg); } else if (typecode == COMPLEX_TYPE) { code = CONJ_EXPR; if (pedantic) pedwarn ("ISO C does not support `~' for complex conjugation"); if (!noconvert) arg = default_conversion (arg); } else { error ("wrong type argument to bit-complement"); return error_mark_node; } break; case ABS_EXPR: if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE || typecode == COMPLEX_TYPE)) { error ("wrong type argument to abs"); return error_mark_node; } else if (!noconvert) arg = default_conversion (arg); break; case CONJ_EXPR: /* Conjugating a real value is a no-op, but allow it anyway. */ if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE || typecode == COMPLEX_TYPE)) { error ("wrong type argument to conjugation"); return error_mark_node; } else if (!noconvert) arg = default_conversion (arg); break; case TRUTH_NOT_EXPR: if (typecode != INTEGER_TYPE && typecode != REAL_TYPE && typecode != POINTER_TYPE && typecode != COMPLEX_TYPE /* These will convert to a pointer. */ && typecode != ARRAY_TYPE && typecode != FUNCTION_TYPE) { error ("wrong type argument to unary exclamation mark"); return error_mark_node; } arg = c_common_truthvalue_conversion (arg); return invert_truthvalue (arg); case NOP_EXPR: break; case REALPART_EXPR: if (TREE_CODE (arg) == COMPLEX_CST) return TREE_REALPART (arg); else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE) return fold (build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg)); else return arg; case IMAGPART_EXPR: if (TREE_CODE (arg) == COMPLEX_CST) return TREE_IMAGPART (arg); else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE) return fold (build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg)); else return convert (TREE_TYPE (arg), integer_zero_node); case PREINCREMENT_EXPR: case POSTINCREMENT_EXPR: case PREDECREMENT_EXPR: case POSTDECREMENT_EXPR: /* Handle complex lvalues (when permitted) by reduction to simpler cases. */ val = unary_complex_lvalue (code, arg, 0); if (val != 0) return val; /* Increment or decrement the real part of the value, and don't change the imaginary part. */ if (typecode == COMPLEX_TYPE) { tree real, imag; if (pedantic) pedwarn ("ISO C does not support `++' and `--' on complex types"); arg = stabilize_reference (arg); real = build_unary_op (REALPART_EXPR, arg, 1); imag = build_unary_op (IMAGPART_EXPR, arg, 1); return build (COMPLEX_EXPR, TREE_TYPE (arg), build_unary_op (code, real, 1), imag); } /* Report invalid types. */ if (typecode != POINTER_TYPE && typecode != INTEGER_TYPE && typecode != REAL_TYPE) { if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR) error ("wrong type argument to increment"); else error ("wrong type argument to decrement"); return error_mark_node; } { tree inc; tree result_type = TREE_TYPE (arg); arg = get_unwidened (arg, 0); argtype = TREE_TYPE (arg); /* Compute the increment. */ if (typecode == POINTER_TYPE) { /* If pointer target is an undefined struct, we just cannot know how to do the arithmetic. */ if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (result_type))) { if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR) error ("increment of pointer to unknown structure"); else error ("decrement of pointer to unknown structure"); } else if ((pedantic || warn_pointer_arith) && (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE || TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE)) { if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR) pedwarn ("wrong type argument to increment"); else pedwarn ("wrong type argument to decrement"); } inc = c_size_in_bytes (TREE_TYPE (result_type)); } else inc = integer_one_node; inc = convert (argtype, inc); /* Handle incrementing a cast-expression. */ while (1) switch (TREE_CODE (arg)) { case NOP_EXPR: case CONVERT_EXPR: case FLOAT_EXPR: case FIX_TRUNC_EXPR: case FIX_FLOOR_EXPR: case FIX_ROUND_EXPR: case FIX_CEIL_EXPR: pedantic_lvalue_warning (CONVERT_EXPR); /* If the real type has the same machine representation as the type it is cast to, we can make better output by adding directly to the inside of the cast. */ if ((TREE_CODE (TREE_TYPE (arg)) == TREE_CODE (TREE_TYPE (TREE_OPERAND (arg, 0)))) && (TYPE_MODE (TREE_TYPE (arg)) == TYPE_MODE (TREE_TYPE (TREE_OPERAND (arg, 0))))) arg = TREE_OPERAND (arg, 0); else { tree incremented, modify, value; if (TREE_CODE (TREE_TYPE (arg)) == BOOLEAN_TYPE) value = boolean_increment (code, arg); else { arg = stabilize_reference (arg); if (code == PREINCREMENT_EXPR || code == PREDECREMENT_EXPR) value = arg; else value = save_expr (arg); incremented = build (((code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR) ? PLUS_EXPR : MINUS_EXPR), argtype, value, inc); TREE_SIDE_EFFECTS (incremented) = 1; modify = build_modify_expr (arg, NOP_EXPR, incremented); value = build (COMPOUND_EXPR, TREE_TYPE (arg), modify, value); } TREE_USED (value) = 1; return value; } break; default: goto give_up; } give_up: /* Complain about anything else that is not a true lvalue. */ if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR) ? "invalid lvalue in increment" : "invalid lvalue in decrement"))) return error_mark_node; /* Report a read-only lvalue. */ if (TREE_READONLY (arg)) readonly_warning (arg, ((code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR) ? "increment" : "decrement")); if (TREE_CODE (TREE_TYPE (arg)) == BOOLEAN_TYPE) val = boolean_increment (code, arg); else val = build (code, TREE_TYPE (arg), arg, inc); TREE_SIDE_EFFECTS (val) = 1; val = convert (result_type, val); if (TREE_CODE (val) != code) TREE_NO_UNUSED_WARNING (val) = 1; return val; } case ADDR_EXPR: /* Note that this operation never does default_conversion. */ /* Let &* cancel out to simplify resulting code. */ if (TREE_CODE (arg) == INDIRECT_REF) { /* Don't let this be an lvalue. */ if (lvalue_p (TREE_OPERAND (arg, 0))) return non_lvalue (TREE_OPERAND (arg, 0)); return TREE_OPERAND (arg, 0); } /* For &x[y], return x+y */ if (TREE_CODE (arg) == ARRAY_REF) { if (!c_mark_addressable (TREE_OPERAND (arg, 0))) return error_mark_node; return build_binary_op (PLUS_EXPR, TREE_OPERAND (arg, 0), TREE_OPERAND (arg, 1), 1); } /* Handle complex lvalues (when permitted) by reduction to simpler cases. */ val = unary_complex_lvalue (code, arg, flag); if (val != 0) return val; #if 0 /* Turned off because inconsistent; float f; *&(int)f = 3.4 stores in int format whereas (int)f = 3.4 stores in float format. */ /* Address of a cast is just a cast of the address of the operand of the cast. */ switch (TREE_CODE (arg)) { case NOP_EXPR: case CONVERT_EXPR: case FLOAT_EXPR: case FIX_TRUNC_EXPR: case FIX_FLOOR_EXPR: case FIX_ROUND_EXPR: case FIX_CEIL_EXPR: if (pedantic) pedwarn ("ISO C forbids the address of a cast expression"); return convert (build_pointer_type (TREE_TYPE (arg)), build_unary_op (ADDR_EXPR, TREE_OPERAND (arg, 0), 0)); } #endif /* Anything not already handled and not a true memory reference or a non-lvalue array is an error. */ else if (typecode != FUNCTION_TYPE && !flag && !lvalue_or_else (arg, "invalid lvalue in unary `&'")) return error_mark_node; /* Ordinary case; arg is a COMPONENT_REF or a decl. */ argtype = TREE_TYPE (arg); /* If the lvalue is const or volatile, merge that into the type to which the address will point. Note that you can't get a restricted pointer by taking the address of something, so we only have to deal with `const' and `volatile' here. */ if ((DECL_P (arg) || TREE_CODE_CLASS (TREE_CODE (arg)) == 'r') && (TREE_READONLY (arg) || TREE_THIS_VOLATILE (arg))) argtype = c_build_type_variant (argtype, TREE_READONLY (arg), TREE_THIS_VOLATILE (arg)); argtype = build_pointer_type (argtype); if (!c_mark_addressable (arg)) return error_mark_node; { tree addr; if (TREE_CODE (arg) == COMPONENT_REF) { tree field = TREE_OPERAND (arg, 1); addr = build_unary_op (ADDR_EXPR, TREE_OPERAND (arg, 0), flag); if (DECL_C_BIT_FIELD (field)) { error ("attempt to take address of bit-field structure member `%s'", IDENTIFIER_POINTER (DECL_NAME (field))); return error_mark_node; } addr = fold (build (PLUS_EXPR, argtype, convert (argtype, addr), convert (argtype, byte_position (field)))); } else addr = build1 (code, argtype, arg); /* Address of a static or external variable or file-scope function counts as a constant. */ if (staticp (arg) && ! (TREE_CODE (arg) == FUNCTION_DECL && DECL_CONTEXT (arg) != 0)) TREE_CONSTANT (addr) = 1; return addr; } default: break; } if (argtype == 0) argtype = TREE_TYPE (arg); return fold (build1 (code, argtype, arg)); } #if 0 /* If CONVERSIONS is a conversion expression or a nested sequence of such, convert ARG with the same conversions in the same order and return the result. */ static tree convert_sequence (conversions, arg) tree conversions; tree arg; { switch (TREE_CODE (conversions)) { case NOP_EXPR: case CONVERT_EXPR: case FLOAT_EXPR: case FIX_TRUNC_EXPR: case FIX_FLOOR_EXPR: case FIX_ROUND_EXPR: case FIX_CEIL_EXPR: return convert (TREE_TYPE (conversions), convert_sequence (TREE_OPERAND (conversions, 0), arg)); default: return arg; } } #endif /* 0 */ /* Return nonzero if REF is an lvalue valid for this language. Lvalues can be assigned, unless their type has TYPE_READONLY. Lvalues can have their address taken, unless they have DECL_REGISTER. */ int lvalue_p (ref) tree ref; { enum tree_code code = TREE_CODE (ref); switch (code) { case REALPART_EXPR: case IMAGPART_EXPR: case COMPONENT_REF: return lvalue_p (TREE_OPERAND (ref, 0)); case COMPOUND_LITERAL_EXPR: case STRING_CST: return 1; case INDIRECT_REF: case ARRAY_REF: case VAR_DECL: case PARM_DECL: case RESULT_DECL: case ERROR_MARK: return (TREE_CODE (TREE_TYPE (ref)) != FUNCTION_TYPE && TREE_CODE (TREE_TYPE (ref)) != METHOD_TYPE); case BIND_EXPR: case RTL_EXPR: return TREE_CODE (TREE_TYPE (ref)) == ARRAY_TYPE; default: return 0; } } /* Return nonzero if REF is an lvalue valid for this language; otherwise, print an error message and return zero. */ int lvalue_or_else (ref, msgid) tree ref; const char *msgid; { int win = lvalue_p (ref); if (! win) error ("%s", msgid); return win; } /* Apply unary lvalue-demanding operator CODE to the expression ARG for certain kinds of expressions which are not really lvalues but which we can accept as lvalues. If FLAG is nonzero, then non-lvalues are OK since we may be converting a non-lvalue array to a pointer in C99. If ARG is not a kind of expression we can handle, return zero. */ static tree unary_complex_lvalue (code, arg, flag) enum tree_code code; tree arg; int flag; { /* Handle (a, b) used as an "lvalue". */ if (TREE_CODE (arg) == COMPOUND_EXPR) { tree real_result = build_unary_op (code, TREE_OPERAND (arg, 1), 0); /* If this returns a function type, it isn't really being used as an lvalue, so don't issue a warning about it. */ if (TREE_CODE (TREE_TYPE (arg)) != FUNCTION_TYPE && !flag) pedantic_lvalue_warning (COMPOUND_EXPR); return build (COMPOUND_EXPR, TREE_TYPE (real_result), TREE_OPERAND (arg, 0), real_result); } /* Handle (a ? b : c) used as an "lvalue". */ if (TREE_CODE (arg) == COND_EXPR) { if (!flag) pedantic_lvalue_warning (COND_EXPR); if (TREE_CODE (TREE_TYPE (arg)) != FUNCTION_TYPE && !flag) pedantic_lvalue_warning (COMPOUND_EXPR); return (build_conditional_expr (TREE_OPERAND (arg, 0), build_unary_op (code, TREE_OPERAND (arg, 1), flag), build_unary_op (code, TREE_OPERAND (arg, 2), flag))); } return 0; } /* If pedantic, warn about improper lvalue. CODE is either COND_EXPR COMPOUND_EXPR, or CONVERT_EXPR (for casts). */ static void pedantic_lvalue_warning (code) enum tree_code code; { if (pedantic) switch (code) { case COND_EXPR: pedwarn ("ISO C forbids use of conditional expressions as lvalues"); break; case COMPOUND_EXPR: pedwarn ("ISO C forbids use of compound expressions as lvalues"); break; default: pedwarn ("ISO C forbids use of cast expressions as lvalues"); break; } } /* Warn about storing in something that is `const'. */ void readonly_warning (arg, msgid) tree arg; const char *msgid; { if (TREE_CODE (arg) == COMPONENT_REF) { if (TYPE_READONLY (TREE_TYPE (TREE_OPERAND (arg, 0)))) readonly_warning (TREE_OPERAND (arg, 0), msgid); else pedwarn ("%s of read-only member `%s'", _(msgid), IDENTIFIER_POINTER (DECL_NAME (TREE_OPERAND (arg, 1)))); } else if (TREE_CODE (arg) == VAR_DECL) pedwarn ("%s of read-only variable `%s'", _(msgid), IDENTIFIER_POINTER (DECL_NAME (arg))); else pedwarn ("%s of read-only location", _(msgid)); } /* Mark EXP saying that we need to be able to take the address of it; it should not be allocated in a register. Returns true if successful. */ bool c_mark_addressable (exp) tree exp; { tree x = exp; while (1) switch (TREE_CODE (x)) { case COMPONENT_REF: if (DECL_C_BIT_FIELD (TREE_OPERAND (x, 1))) { error ("cannot take address of bit-field `%s'", IDENTIFIER_POINTER (DECL_NAME (TREE_OPERAND (x, 1)))); return false; } /* ... fall through ... */ case ADDR_EXPR: case ARRAY_REF: case REALPART_EXPR: case IMAGPART_EXPR: x = TREE_OPERAND (x, 0); break; case COMPOUND_LITERAL_EXPR: case CONSTRUCTOR: TREE_ADDRESSABLE (x) = 1; return true; case VAR_DECL: case CONST_DECL: case PARM_DECL: case RESULT_DECL: if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x) && DECL_NONLOCAL (x)) { if (TREE_PUBLIC (x)) { error ("global register variable `%s' used in nested function", IDENTIFIER_POINTER (DECL_NAME (x))); return false; } pedwarn ("register variable `%s' used in nested function", IDENTIFIER_POINTER (DECL_NAME (x))); } else if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x)) { if (TREE_PUBLIC (x)) { error ("address of global register variable `%s' requested", IDENTIFIER_POINTER (DECL_NAME (x))); return false; } /* If we are making this addressable due to its having volatile components, give a different error message. Also handle the case of an unnamed parameter by not trying to give the name. */ else if (C_TYPE_FIELDS_VOLATILE (TREE_TYPE (x))) { error ("cannot put object with volatile field into register"); return false; } pedwarn ("address of register variable `%s' requested", IDENTIFIER_POINTER (DECL_NAME (x))); } put_var_into_stack (x); /* drops in */ case FUNCTION_DECL: TREE_ADDRESSABLE (x) = 1; #if 0 /* poplevel deals with this now. */ if (DECL_CONTEXT (x) == 0) TREE_ADDRESSABLE (DECL_ASSEMBLER_NAME (x)) = 1; #endif default: return true; } } /* Build and return a conditional expression IFEXP ? OP1 : OP2. */ tree build_conditional_expr (ifexp, op1, op2) tree ifexp, op1, op2; { tree type1; tree type2; enum tree_code code1; enum tree_code code2; tree result_type = NULL; tree orig_op1 = op1, orig_op2 = op2; ifexp = c_common_truthvalue_conversion (default_conversion (ifexp)); #if 0 /* Produces wrong result if within sizeof. */ /* Don't promote the operands separately if they promote the same way. Return the unpromoted type and let the combined value get promoted if necessary. */ if (TREE_TYPE (op1) == TREE_TYPE (op2) && TREE_CODE (TREE_TYPE (op1)) != ARRAY_TYPE && TREE_CODE (TREE_TYPE (op1)) != ENUMERAL_TYPE && TREE_CODE (TREE_TYPE (op1)) != FUNCTION_TYPE) { if (TREE_CODE (ifexp) == INTEGER_CST) return pedantic_non_lvalue (integer_zerop (ifexp) ? op2 : op1); return fold (build (COND_EXPR, TREE_TYPE (op1), ifexp, op1, op2)); } #endif /* Promote both alternatives. */ if (TREE_CODE (TREE_TYPE (op1)) != VOID_TYPE) op1 = default_conversion (op1); if (TREE_CODE (TREE_TYPE (op2)) != VOID_TYPE) op2 = default_conversion (op2); if (TREE_CODE (ifexp) == ERROR_MARK || TREE_CODE (TREE_TYPE (op1)) == ERROR_MARK || TREE_CODE (TREE_TYPE (op2)) == ERROR_MARK) return error_mark_node; type1 = TREE_TYPE (op1); code1 = TREE_CODE (type1); type2 = TREE_TYPE (op2); code2 = TREE_CODE (type2); /* Quickly detect the usual case where op1 and op2 have the same type after promotion. */ if (TYPE_MAIN_VARIANT (type1) == TYPE_MAIN_VARIANT (type2)) { if (type1 == type2) result_type = type1; else result_type = TYPE_MAIN_VARIANT (type1); } else if ((code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE) && (code2 == INTEGER_TYPE || code2 == REAL_TYPE || code2 == COMPLEX_TYPE)) { result_type = common_type (type1, type2); /* If -Wsign-compare, warn here if type1 and type2 have different signedness. We'll promote the signed to unsigned and later code won't know it used to be different. Do this check on the original types, so that explicit casts will be considered, but default promotions won't. */ if ((warn_sign_compare < 0 ? extra_warnings : warn_sign_compare) && !skip_evaluation) { int unsigned_op1 = TREE_UNSIGNED (TREE_TYPE (orig_op1)); int unsigned_op2 = TREE_UNSIGNED (TREE_TYPE (orig_op2)); if (unsigned_op1 ^ unsigned_op2) { /* Do not warn if the result type is signed, since the signed type will only be chosen if it can represent all the values of the unsigned type. */ if (! TREE_UNSIGNED (result_type)) /* OK */; /* Do not warn if the signed quantity is an unsuffixed integer literal (or some static constant expression involving such literals) and it is non-negative. */ else if ((unsigned_op2 && c_tree_expr_nonnegative_p (op1)) || (unsigned_op1 && c_tree_expr_nonnegative_p (op2))) /* OK */; else warning ("signed and unsigned type in conditional expression"); } } } else if (code1 == VOID_TYPE || code2 == VOID_TYPE) { if (pedantic && (code1 != VOID_TYPE || code2 != VOID_TYPE)) pedwarn ("ISO C forbids conditional expr with only one void side"); result_type = void_type_node; } else if (code1 == POINTER_TYPE && code2 == POINTER_TYPE) { if (comp_target_types (type1, type2, 1)) result_type = common_type (type1, type2); else if (integer_zerop (op1) && TREE_TYPE (type1) == void_type_node && TREE_CODE (orig_op1) != NOP_EXPR) result_type = qualify_type (type2, type1); else if (integer_zerop (op2) && TREE_TYPE (type2) == void_type_node && TREE_CODE (orig_op2) != NOP_EXPR) result_type = qualify_type (type1, type2); else if (VOID_TYPE_P (TREE_TYPE (type1))) { if (pedantic && TREE_CODE (TREE_TYPE (type2)) == FUNCTION_TYPE) pedwarn ("ISO C forbids conditional expr between `void *' and function pointer"); result_type = build_pointer_type (qualify_type (TREE_TYPE (type1), TREE_TYPE (type2))); } else if (VOID_TYPE_P (TREE_TYPE (type2))) { if (pedantic && TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE) pedwarn ("ISO C forbids conditional expr between `void *' and function pointer"); result_type = build_pointer_type (qualify_type (TREE_TYPE (type2), TREE_TYPE (type1))); } else { pedwarn ("pointer type mismatch in conditional expression"); result_type = build_pointer_type (void_type_node); } } else if (code1 == POINTER_TYPE && code2 == INTEGER_TYPE) { if (! integer_zerop (op2)) pedwarn ("pointer/integer type mismatch in conditional expression"); else { op2 = null_pointer_node; } result_type = type1; } else if (code2 == POINTER_TYPE && code1 == INTEGER_TYPE) { if (!integer_zerop (op1)) pedwarn ("pointer/integer type mismatch in conditional expression"); else { op1 = null_pointer_node; } result_type = type2; } if (!result_type) { if (flag_cond_mismatch) result_type = void_type_node; else { error ("type mismatch in conditional expression"); return error_mark_node; } } /* Merge const and volatile flags of the incoming types. */ result_type = build_type_variant (result_type, TREE_READONLY (op1) || TREE_READONLY (op2), TREE_THIS_VOLATILE (op1) || TREE_THIS_VOLATILE (op2)); if (result_type != TREE_TYPE (op1)) op1 = convert_and_check (result_type, op1); if (result_type != TREE_TYPE (op2)) op2 = convert_and_check (result_type, op2); if (TREE_CODE (ifexp) == INTEGER_CST) return pedantic_non_lvalue (integer_zerop (ifexp) ? op2 : op1); return fold (build (COND_EXPR, result_type, ifexp, op1, op2)); } /* Given a list of expressions, return a compound expression that performs them all and returns the value of the last of them. */ tree build_compound_expr (list) tree list; { return internal_build_compound_expr (list, TRUE); } static tree internal_build_compound_expr (list, first_p) tree list; int first_p; { tree rest; if (TREE_CHAIN (list) == 0) { /* Convert arrays and functions to pointers when there really is a comma operator. */ if (!first_p) TREE_VALUE (list) = default_function_array_conversion (TREE_VALUE (list)); #if 0 /* If something inside inhibited lvalueness, we should not override. */ /* Consider (x, y+0), which is not an lvalue since y+0 is not. */ /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */ if (TREE_CODE (list) == NON_LVALUE_EXPR) list = TREE_OPERAND (list, 0); #endif /* Don't let (0, 0) be null pointer constant. */ if (!first_p && integer_zerop (TREE_VALUE (list))) return non_lvalue (TREE_VALUE (list)); return TREE_VALUE (list); } rest = internal_build_compound_expr (TREE_CHAIN (list), FALSE); if (! TREE_SIDE_EFFECTS (TREE_VALUE (list))) { /* The left-hand operand of a comma expression is like an expression statement: with -W or -Wunused, we should warn if it doesn't have any side-effects, unless it was explicitly cast to (void). */ if ((extra_warnings || warn_unused_value) && ! (TREE_CODE (TREE_VALUE (list)) == CONVERT_EXPR && VOID_TYPE_P (TREE_TYPE (TREE_VALUE (list))))) warning ("left-hand operand of comma expression has no effect"); /* When pedantic, a compound expression can be neither an lvalue nor an integer constant expression. */ if (! pedantic) return rest; } /* With -Wunused, we should also warn if the left-hand operand does have side-effects, but computes a value which is not used. For example, in `foo() + bar(), baz()' the result of the `+' operator is not used, so we should issue a warning. */ else if (warn_unused_value) warn_if_unused_value (TREE_VALUE (list)); return build (COMPOUND_EXPR, TREE_TYPE (rest), TREE_VALUE (list), rest); } /* Build an expression representing a cast to type TYPE of expression EXPR. */ tree build_c_cast (type, expr) tree type; tree expr; { tree value = expr; if (type == error_mark_node || expr == error_mark_node) return error_mark_node; /* The ObjC front-end uses TYPE_MAIN_VARIANT to tie together types differing only in qualifications. But when constructing cast expressions, the protocols do matter and must be kept around. */ if (!flag_objc || !objc_is_id (type)) type = TYPE_MAIN_VARIANT (type); #if 0 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */ if (TREE_CODE (value) == NON_LVALUE_EXPR) value = TREE_OPERAND (value, 0); #endif if (TREE_CODE (type) == ARRAY_TYPE) { error ("cast specifies array type"); return error_mark_node; } if (TREE_CODE (type) == FUNCTION_TYPE) { error ("cast specifies function type"); return error_mark_node; } if (type == TYPE_MAIN_VARIANT (TREE_TYPE (value))) { if (pedantic) { if (TREE_CODE (type) == RECORD_TYPE || TREE_CODE (type) == UNION_TYPE) pedwarn ("ISO C forbids casting nonscalar to the same type"); } } else if (TREE_CODE (type) == UNION_TYPE) { tree field; value = default_function_array_conversion (value); for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field)) if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (field)), TYPE_MAIN_VARIANT (TREE_TYPE (value)))) break; if (field) { const char *name; tree t; if (pedantic) pedwarn ("ISO C forbids casts to union type"); if (TYPE_NAME (type) != 0) { if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE) name = IDENTIFIER_POINTER (TYPE_NAME (type)); else name = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (type))); } else name = ""; t = digest_init (type, build (CONSTRUCTOR, type, NULL_TREE, build_tree_list (field, value)), 0); TREE_CONSTANT (t) = TREE_CONSTANT (value); return t; } error ("cast to union type from type not present in union"); return error_mark_node; } else { tree otype, ovalue; /* If casting to void, avoid the error that would come from default_conversion in the case of a non-lvalue array. */ if (type == void_type_node) return build1 (CONVERT_EXPR, type, value); /* Convert functions and arrays to pointers, but don't convert any other types. */ value = default_function_array_conversion (value); otype = TREE_TYPE (value); /* Optionally warn about potentially worrisome casts. */ if (warn_cast_qual && TREE_CODE (type) == POINTER_TYPE && TREE_CODE (otype) == POINTER_TYPE) { tree in_type = type; tree in_otype = otype; int added = 0; int discarded = 0; /* Check that the qualifiers on IN_TYPE are a superset of the qualifiers of IN_OTYPE. The outermost level of POINTER_TYPE nodes is uninteresting and we stop as soon as we hit a non-POINTER_TYPE node on either type. */ do { in_otype = TREE_TYPE (in_otype); in_type = TREE_TYPE (in_type); /* GNU C allows cv-qualified function types. 'const' means the function is very pure, 'volatile' means it can't return. We need to warn when such qualifiers are added, not when they're taken away. */ if (TREE_CODE (in_otype) == FUNCTION_TYPE && TREE_CODE (in_type) == FUNCTION_TYPE) added |= (TYPE_QUALS (in_type) & ~TYPE_QUALS (in_otype)); else discarded |= (TYPE_QUALS (in_otype) & ~TYPE_QUALS (in_type)); } while (TREE_CODE (in_type) == POINTER_TYPE && TREE_CODE (in_otype) == POINTER_TYPE); if (added) warning ("cast adds new qualifiers to function type"); if (discarded) /* There are qualifiers present in IN_OTYPE that are not present in IN_TYPE. */ warning ("cast discards qualifiers from pointer target type"); } /* Warn about possible alignment problems. */ if (STRICT_ALIGNMENT && warn_cast_align && TREE_CODE (type) == POINTER_TYPE && TREE_CODE (otype) == POINTER_TYPE && TREE_CODE (TREE_TYPE (otype)) != VOID_TYPE && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE /* Don't warn about opaque types, where the actual alignment restriction is unknown. */ && !((TREE_CODE (TREE_TYPE (otype)) == UNION_TYPE || TREE_CODE (TREE_TYPE (otype)) == RECORD_TYPE) && TYPE_MODE (TREE_TYPE (otype)) == VOIDmode) && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (otype))) warning ("cast increases required alignment of target type"); if (TREE_CODE (type) == INTEGER_TYPE && TREE_CODE (otype) == POINTER_TYPE && TYPE_PRECISION (type) != TYPE_PRECISION (otype) && !TREE_CONSTANT (value)) warning ("cast from pointer to integer of different size"); if (warn_bad_function_cast && TREE_CODE (value) == CALL_EXPR && TREE_CODE (type) != TREE_CODE (otype)) warning ("cast does not match function type"); if (TREE_CODE (type) == POINTER_TYPE && TREE_CODE (otype) == INTEGER_TYPE && TYPE_PRECISION (type) != TYPE_PRECISION (otype) /* Don't warn about converting any constant. */ && !TREE_CONSTANT (value)) warning ("cast to pointer from integer of different size"); if (TREE_CODE (type) == POINTER_TYPE && TREE_CODE (otype) == POINTER_TYPE && TREE_CODE (expr) == ADDR_EXPR && DECL_P (TREE_OPERAND (expr, 0)) && flag_strict_aliasing && warn_strict_aliasing && !VOID_TYPE_P (TREE_TYPE (type))) { /* Casting the address of a decl to non void pointer. Warn if the cast breaks type based aliasing. */ if (!COMPLETE_TYPE_P (TREE_TYPE (type))) warning ("type-punning to incomplete type might break strict-aliasing rules"); else if (!alias_sets_conflict_p (get_alias_set (TREE_TYPE (TREE_OPERAND (expr, 0))), get_alias_set (TREE_TYPE (type)))) warning ("dereferencing type-punned pointer will break strict-aliasing rules"); } ovalue = value; value = convert (type, value); /* Ignore any integer overflow caused by the cast. */ if (TREE_CODE (value) == INTEGER_CST) { TREE_OVERFLOW (value) = TREE_OVERFLOW (ovalue); TREE_CONSTANT_OVERFLOW (value) = TREE_CONSTANT_OVERFLOW (ovalue); } } /* Pedantically, don't let (void *) (FOO *) 0 be a null pointer constant. */ if (pedantic && TREE_CODE (value) == INTEGER_CST && TREE_CODE (expr) == INTEGER_CST && TREE_CODE (TREE_TYPE (expr)) != INTEGER_TYPE) value = non_lvalue (value); /* If pedantic, don't let a cast be an lvalue. */ if (value == expr && pedantic) value = non_lvalue (value); return value; } /* Interpret a cast of expression EXPR to type TYPE. */ tree c_cast_expr (type, expr) tree type, expr; { int saved_wsp = warn_strict_prototypes; /* This avoids warnings about unprototyped casts on integers. E.g. "#define SIG_DFL (void(*)())0". */ if (TREE_CODE (expr) == INTEGER_CST) warn_strict_prototypes = 0; type = groktypename (type); warn_strict_prototypes = saved_wsp; return build_c_cast (type, expr); } /* Build an assignment expression of lvalue LHS from value RHS. MODIFYCODE is the code for a binary operator that we use to combine the old value of LHS with RHS to get the new value. Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment. */ tree build_modify_expr (lhs, modifycode, rhs) tree lhs, rhs; enum tree_code modifycode; { tree result; tree newrhs; tree lhstype = TREE_TYPE (lhs); tree olhstype = lhstype; /* Types that aren't fully specified cannot be used in assignments. */ lhs = require_complete_type (lhs); /* Avoid duplicate error messages from operands that had errors. */ if (TREE_CODE (lhs) == ERROR_MARK || TREE_CODE (rhs) == ERROR_MARK) return error_mark_node; /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */ /* Do not use STRIP_NOPS here. We do not want an enumerator whose value is 0 to count as a null pointer constant. */ if (TREE_CODE (rhs) == NON_LVALUE_EXPR) rhs = TREE_OPERAND (rhs, 0); newrhs = rhs; /* Handle control structure constructs used as "lvalues". */ switch (TREE_CODE (lhs)) { /* Handle (a, b) used as an "lvalue". */ case COMPOUND_EXPR: pedantic_lvalue_warning (COMPOUND_EXPR); newrhs = build_modify_expr (TREE_OPERAND (lhs, 1), modifycode, rhs); if (TREE_CODE (newrhs) == ERROR_MARK) return error_mark_node; return build (COMPOUND_EXPR, lhstype, TREE_OPERAND (lhs, 0), newrhs); /* Handle (a ? b : c) used as an "lvalue". */ case COND_EXPR: pedantic_lvalue_warning (COND_EXPR); rhs = save_expr (rhs); { /* Produce (a ? (b = rhs) : (c = rhs)) except that the RHS goes through a save-expr so the code to compute it is only emitted once. */ tree cond = build_conditional_expr (TREE_OPERAND (lhs, 0), build_modify_expr (TREE_OPERAND (lhs, 1), modifycode, rhs), build_modify_expr (TREE_OPERAND (lhs, 2), modifycode, rhs)); if (TREE_CODE (cond) == ERROR_MARK) return cond; /* Make sure the code to compute the rhs comes out before the split. */ return build (COMPOUND_EXPR, TREE_TYPE (lhs), /* But cast it to void to avoid an "unused" error. */ convert (void_type_node, rhs), cond); } default: break; } /* If a binary op has been requested, combine the old LHS value with the RHS producing the value we should actually store into the LHS. */ if (modifycode != NOP_EXPR) { lhs = stabilize_reference (lhs); newrhs = build_binary_op (modifycode, lhs, rhs, 1); } /* Handle a cast used as an "lvalue". We have already performed any binary operator using the value as cast. Now convert the result to the cast type of the lhs, and then true type of the lhs and store it there; then convert result back to the cast type to be the value of the assignment. */ switch (TREE_CODE (lhs)) { case NOP_EXPR: case CONVERT_EXPR: case FLOAT_EXPR: case FIX_TRUNC_EXPR: case FIX_FLOOR_EXPR: case FIX_ROUND_EXPR: case FIX_CEIL_EXPR: newrhs = default_function_array_conversion (newrhs); { tree inner_lhs = TREE_OPERAND (lhs, 0); tree result; result = build_modify_expr (inner_lhs, NOP_EXPR, convert (TREE_TYPE (inner_lhs), convert (lhstype, newrhs))); if (TREE_CODE (result) == ERROR_MARK) return result; pedantic_lvalue_warning (CONVERT_EXPR); return convert (TREE_TYPE (lhs), result); } default: break; } /* Now we have handled acceptable kinds of LHS that are not truly lvalues. Reject anything strange now. */ if (!lvalue_or_else (lhs, "invalid lvalue in assignment")) return error_mark_node; /* Warn about storing in something that is `const'. */ if (TREE_READONLY (lhs) || TYPE_READONLY (lhstype) || ((TREE_CODE (lhstype) == RECORD_TYPE || TREE_CODE (lhstype) == UNION_TYPE) && C_TYPE_FIELDS_READONLY (lhstype))) readonly_warning (lhs, "assignment"); /* If storing into a structure or union member, it has probably been given type `int'. Compute the type that would go with the actual amount of storage the member occupies. */ if (TREE_CODE (lhs) == COMPONENT_REF && (TREE_CODE (lhstype) == INTEGER_TYPE || TREE_CODE (lhstype) == BOOLEAN_TYPE || TREE_CODE (lhstype) == REAL_TYPE || TREE_CODE (lhstype) == ENUMERAL_TYPE)) lhstype = TREE_TYPE (get_unwidened (lhs, 0)); /* If storing in a field that is in actuality a short or narrower than one, we must store in the field in its actual type. */ if (lhstype != TREE_TYPE (lhs)) { lhs = copy_node (lhs); TREE_TYPE (lhs) = lhstype; } /* Convert new value to destination type. */ newrhs = convert_for_assignment (lhstype, newrhs, _("assignment"), NULL_TREE, NULL_TREE, 0); if (TREE_CODE (newrhs) == ERROR_MARK) return error_mark_node; /* Scan operands */ result = build (MODIFY_EXPR, lhstype, lhs, newrhs); TREE_SIDE_EFFECTS (result) = 1; /* If we got the LHS in a different type for storing in, convert the result back to the nominal type of LHS so that the value we return always has the same type as the LHS argument. */ if (olhstype == TREE_TYPE (result)) return result; return convert_for_assignment (olhstype, result, _("assignment"), NULL_TREE, NULL_TREE, 0); } /* Convert value RHS to type TYPE as preparation for an assignment to an lvalue of type TYPE. The real work of conversion is done by `convert'. The purpose of this function is to generate error messages for assignments that are not allowed in C. ERRTYPE is a string to use in error messages: "assignment", "return", etc. If it is null, this is parameter passing for a function call (and different error messages are output). FUNNAME is the name of the function being called, as an IDENTIFIER_NODE, or null. PARMNUM is the number of the argument, for printing in error messages. */ static tree convert_for_assignment (type, rhs, errtype, fundecl, funname, parmnum) tree type, rhs; const char *errtype; tree fundecl, funname; int parmnum; { enum tree_code codel = TREE_CODE (type); tree rhstype; enum tree_code coder; /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */ /* Do not use STRIP_NOPS here. We do not want an enumerator whose value is 0 to count as a null pointer constant. */ if (TREE_CODE (rhs) == NON_LVALUE_EXPR) rhs = TREE_OPERAND (rhs, 0); if (TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE || TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE) rhs = default_conversion (rhs); else if (optimize && TREE_CODE (rhs) == VAR_DECL) rhs = decl_constant_value_for_broken_optimization (rhs); rhstype = TREE_TYPE (rhs); coder = TREE_CODE (rhstype); if (coder == ERROR_MARK) return error_mark_node; if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (rhstype)) { overflow_warning (rhs); /* Check for Objective-C protocols. This will automatically issue a warning if there are protocol violations. No need to use the return value. */ if (flag_objc) objc_comptypes (type, rhstype, 0); return rhs; } if (coder == VOID_TYPE) { error ("void value not ignored as it ought to be"); return error_mark_node; } /* A type converts to a reference to it. This code doesn't fully support references, it's just for the special case of va_start and va_copy. */ if (codel == REFERENCE_TYPE && comptypes (TREE_TYPE (type), TREE_TYPE (rhs)) == 1) { if (!lvalue_p (rhs)) { error ("cannot pass rvalue to reference parameter"); return error_mark_node; } if (!c_mark_addressable (rhs)) return error_mark_node; rhs = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (rhs)), rhs); /* We already know that these two types are compatible, but they may not be exactly identical. In fact, `TREE_TYPE (type)' is likely to be __builtin_va_list and `TREE_TYPE (rhs)' is likely to be va_list, a typedef to __builtin_va_list, which is different enough that it will cause problems later. */ if (TREE_TYPE (TREE_TYPE (rhs)) != TREE_TYPE (type)) rhs = build1 (NOP_EXPR, build_pointer_type (TREE_TYPE (type)), rhs); rhs = build1 (NOP_EXPR, type, rhs); return rhs; } /* Arithmetic types all interconvert, and enum is treated like int. */ else if ((codel == INTEGER_TYPE || codel == REAL_TYPE || codel == ENUMERAL_TYPE || codel == COMPLEX_TYPE || codel == BOOLEAN_TYPE) && (coder == INTEGER_TYPE || coder == REAL_TYPE || coder == ENUMERAL_TYPE || coder == COMPLEX_TYPE || coder == BOOLEAN_TYPE)) return convert_and_check (type, rhs); /* Conversion to a transparent union from its member types. This applies only to function arguments. */ else if (codel == UNION_TYPE && TYPE_TRANSPARENT_UNION (type) && ! errtype) { tree memb_types; tree marginal_memb_type = 0; for (memb_types = TYPE_FIELDS (type); memb_types; memb_types = TREE_CHAIN (memb_types)) { tree memb_type = TREE_TYPE (memb_types); if (comptypes (TYPE_MAIN_VARIANT (memb_type), TYPE_MAIN_VARIANT (rhstype))) break; if (TREE_CODE (memb_type) != POINTER_TYPE) continue; if (coder == POINTER_TYPE) { tree ttl = TREE_TYPE (memb_type); tree ttr = TREE_TYPE (rhstype); /* Any non-function converts to a [const][volatile] void * and vice versa; otherwise, targets must be the same. Meanwhile, the lhs target must have all the qualifiers of the rhs. */ if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr) || comp_target_types (memb_type, rhstype, 0)) { /* If this type won't generate any warnings, use it. */ if (TYPE_QUALS (ttl) == TYPE_QUALS (ttr) || ((TREE_CODE (ttr) == FUNCTION_TYPE && TREE_CODE (ttl) == FUNCTION_TYPE) ? ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr)) == TYPE_QUALS (ttr)) : ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr)) == TYPE_QUALS (ttl)))) break; /* Keep looking for a better type, but remember this one. */ if (! marginal_memb_type) marginal_memb_type = memb_type; } } /* Can convert integer zero to any pointer type. */ if (integer_zerop (rhs) || (TREE_CODE (rhs) == NOP_EXPR && integer_zerop (TREE_OPERAND (rhs, 0)))) { rhs = null_pointer_node; break; } } if (memb_types || marginal_memb_type) { if (! memb_types) { /* We have only a marginally acceptable member type; it needs a warning. */ tree ttl = TREE_TYPE (marginal_memb_type); tree ttr = TREE_TYPE (rhstype); /* Const and volatile mean something different for function types, so the usual warnings are not appropriate. */ if (TREE_CODE (ttr) == FUNCTION_TYPE && TREE_CODE (ttl) == FUNCTION_TYPE) { /* Because const and volatile on functions are restrictions that say the function will not do certain things, it is okay to use a const or volatile function where an ordinary one is wanted, but not vice-versa. */ if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr)) warn_for_assignment ("%s makes qualified function pointer from unqualified", errtype, funname, parmnum); } else if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl)) warn_for_assignment ("%s discards qualifiers from pointer target type", errtype, funname, parmnum); } if (pedantic && ! DECL_IN_SYSTEM_HEADER (fundecl)) pedwarn ("ISO C prohibits argument conversion to union type"); return build1 (NOP_EXPR, type, rhs); } } /* Conversions among pointers */ else if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE) && (coder == codel)) { tree ttl = TREE_TYPE (type); tree ttr = TREE_TYPE (rhstype); /* Any non-function converts to a [const][volatile] void * and vice versa; otherwise, targets must be the same. Meanwhile, the lhs target must have all the qualifiers of the rhs. */ if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr) || comp_target_types (type, rhstype, 0) || (c_common_unsigned_type (TYPE_MAIN_VARIANT (ttl)) == c_common_unsigned_type (TYPE_MAIN_VARIANT (ttr)))) { if (pedantic && ((VOID_TYPE_P (ttl) && TREE_CODE (ttr) == FUNCTION_TYPE) || (VOID_TYPE_P (ttr) /* Check TREE_CODE to catch cases like (void *) (char *) 0 which are not ANSI null ptr constants. */ && (!integer_zerop (rhs) || TREE_CODE (rhs) == NOP_EXPR) && TREE_CODE (ttl) == FUNCTION_TYPE))) warn_for_assignment ("ISO C forbids %s between function pointer and `void *'", errtype, funname, parmnum); /* Const and volatile mean something different for function types, so the usual warnings are not appropriate. */ else if (TREE_CODE (ttr) != FUNCTION_TYPE && TREE_CODE (ttl) != FUNCTION_TYPE) { if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl)) warn_for_assignment ("%s discards qualifiers from pointer target type", errtype, funname, parmnum); /* If this is not a case of ignoring a mismatch in signedness, no warning. */ else if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr) || comp_target_types (type, rhstype, 0)) ; /* If there is a mismatch, do warn. */ else if (pedantic) warn_for_assignment ("pointer targets in %s differ in signedness", errtype, funname, parmnum); } else if (TREE_CODE (ttl) == FUNCTION_TYPE && TREE_CODE (ttr) == FUNCTION_TYPE) { /* Because const and volatile on functions are restrictions that say the function will not do certain things, it is okay to use a const or volatile function where an ordinary one is wanted, but not vice-versa. */ if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr)) warn_for_assignment ("%s makes qualified function pointer from unqualified", errtype, funname, parmnum); } } else warn_for_assignment ("%s from incompatible pointer type", errtype, funname, parmnum); return convert (type, rhs); } else if (codel == POINTER_TYPE && coder == INTEGER_TYPE) { /* An explicit constant 0 can convert to a pointer, or one that results from arithmetic, even including a cast to integer type. */ if (! (TREE_CODE (rhs) == INTEGER_CST && integer_zerop (rhs)) && ! (TREE_CODE (rhs) == NOP_EXPR && TREE_CODE (TREE_TYPE (rhs)) == INTEGER_TYPE && TREE_CODE (TREE_OPERAND (rhs, 0)) == INTEGER_CST && integer_zerop (TREE_OPERAND (rhs, 0)))) { warn_for_assignment ("%s makes pointer from integer without a cast", errtype, funname, parmnum); return convert (type, rhs); } return null_pointer_node; } else if (codel == INTEGER_TYPE && coder == POINTER_TYPE) { warn_for_assignment ("%s makes integer from pointer without a cast", errtype, funname, parmnum); return convert (type, rhs); } else if (codel == BOOLEAN_TYPE && coder == POINTER_TYPE) return convert (type, rhs); if (!errtype) { if (funname) { tree selector = objc_message_selector (); if (selector && parmnum > 2) error ("incompatible type for argument %d of `%s'", parmnum - 2, IDENTIFIER_POINTER (selector)); else error ("incompatible type for argument %d of `%s'", parmnum, IDENTIFIER_POINTER (funname)); } else error ("incompatible type for argument %d of indirect function call", parmnum); } else error ("incompatible types in %s", errtype); return error_mark_node; } /* Convert VALUE for assignment into inlined parameter PARM. */ tree c_convert_parm_for_inlining (parm, value, fn) tree parm, value, fn; { tree ret, type; /* If FN was prototyped, the value has been converted already in convert_arguments. */ if (! value || TYPE_ARG_TYPES (TREE_TYPE (fn))) return value; type = TREE_TYPE (parm); ret = convert_for_assignment (type, value, (char *) 0 /* arg passing */, fn, DECL_NAME (fn), 0); if (PROMOTE_PROTOTYPES && INTEGRAL_TYPE_P (type) && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))) ret = default_conversion (ret); return ret; } /* Print a warning using MSGID. It gets OPNAME as its one parameter. if OPNAME is null and ARGNUM is 0, it is replaced by "passing arg of `FUNCTION'". Otherwise if OPNAME is null, it is replaced by "passing arg ARGNUM of `FUNCTION'". FUNCTION and ARGNUM are handled specially if we are building an Objective-C selector. */ static void warn_for_assignment (msgid, opname, function, argnum) const char *msgid; const char *opname; tree function; int argnum; { if (opname == 0) { tree selector = objc_message_selector (); char * new_opname; if (selector && argnum > 2) { function = selector; argnum -= 2; } if (argnum == 0) { if (function) { /* Function name is known; supply it. */ const char *const argstring = _("passing arg of `%s'"); new_opname = (char *) alloca (IDENTIFIER_LENGTH (function) + strlen (argstring) + 1 + 1); sprintf (new_opname, argstring, IDENTIFIER_POINTER (function)); } else { /* Function name unknown (call through ptr). */ const char *const argnofun = _("passing arg of pointer to function"); new_opname = (char *) alloca (strlen (argnofun) + 1 + 1); sprintf (new_opname, argnofun); } } else if (function) { /* Function name is known; supply it. */ const char *const argstring = _("passing arg %d of `%s'"); new_opname = (char *) alloca (IDENTIFIER_LENGTH (function) + strlen (argstring) + 1 + 25 /*%d*/ + 1); sprintf (new_opname, argstring, argnum, IDENTIFIER_POINTER (function)); } else { /* Function name unknown (call through ptr); just give arg number. */ const char *const argnofun = _("passing arg %d of pointer to function"); new_opname = (char *) alloca (strlen (argnofun) + 1 + 25 /*%d*/ + 1); sprintf (new_opname, argnofun, argnum); } opname = new_opname; } pedwarn (msgid, opname); } /* If VALUE is a compound expr all of whose expressions are constant, then return its value. Otherwise, return error_mark_node. This is for handling COMPOUND_EXPRs as initializer elements which is allowed with a warning when -pedantic is specified. */ static tree valid_compound_expr_initializer (value, endtype) tree value; tree endtype; { if (TREE_CODE (value) == COMPOUND_EXPR) { if (valid_compound_expr_initializer (TREE_OPERAND (value, 0), endtype) == error_mark_node) return error_mark_node; return valid_compound_expr_initializer (TREE_OPERAND (value, 1), endtype); } else if (! TREE_CONSTANT (value) && ! initializer_constant_valid_p (value, endtype)) return error_mark_node; else return value; } /* Perform appropriate conversions on the initial value of a variable, store it in the declaration DECL, and print any error messages that are appropriate. If the init is invalid, store an ERROR_MARK. */ void store_init_value (decl, init) tree decl, init; { tree value, type; /* If variable's type was invalidly declared, just ignore it. */ type = TREE_TYPE (decl); if (TREE_CODE (type) == ERROR_MARK) return; /* Digest the specified initializer into an expression. */ value = digest_init (type, init, TREE_STATIC (decl)); /* Store the expression if valid; else report error. */ #if 0 /* Note that this is the only place we can detect the error in a case such as struct foo bar = (struct foo) { x, y }; where there is one initial value which is a constructor expression. */ if (value == error_mark_node) ; else if (TREE_STATIC (decl) && ! TREE_CONSTANT (value)) { error ("initializer for static variable is not constant"); value = error_mark_node; } else if (TREE_STATIC (decl) && initializer_constant_valid_p (value, TREE_TYPE (value)) == 0) { error ("initializer for static variable uses complicated arithmetic"); value = error_mark_node; } else { if (pedantic && TREE_CODE (value) == CONSTRUCTOR) { if (! TREE_CONSTANT (value)) pedwarn ("aggregate initializer is not constant"); else if (! TREE_STATIC (value)) pedwarn ("aggregate initializer uses complicated arithmetic"); } } #endif if (warn_traditional && !in_system_header && AGGREGATE_TYPE_P (TREE_TYPE (decl)) && ! TREE_STATIC (decl)) warning ("traditional C rejects automatic aggregate initialization"); DECL_INITIAL (decl) = value; /* ANSI wants warnings about out-of-range constant initializers. */ STRIP_TYPE_NOPS (value); constant_expression_warning (value); /* Check if we need to set array size from compound literal size. */ if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type) == 0 && value != error_mark_node) { tree inside_init = init; if (TREE_CODE (init) == NON_LVALUE_EXPR) inside_init = TREE_OPERAND (init, 0); inside_init = fold (inside_init); if (TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR) { tree decl = COMPOUND_LITERAL_EXPR_DECL (inside_init); if (TYPE_DOMAIN (TREE_TYPE (decl))) { /* For int foo[] = (int [3]){1}; we need to set array size now since later on array initializer will be just the brace enclosed list of the compound literal. */ TYPE_DOMAIN (type) = TYPE_DOMAIN (TREE_TYPE (decl)); layout_type (type); layout_decl (decl, 0); } } } } /* Methods for storing and printing names for error messages. */ /* Implement a spelling stack that allows components of a name to be pushed and popped. Each element on the stack is this structure. */ struct spelling { int kind; union { int i; const char *s; } u; }; #define SPELLING_STRING 1 #define SPELLING_MEMBER 2 #define SPELLING_BOUNDS 3 static struct spelling *spelling; /* Next stack element (unused). */ static struct spelling *spelling_base; /* Spelling stack base. */ static int spelling_size; /* Size of the spelling stack. */ /* Macros to save and restore the spelling stack around push_... functions. Alternative to SAVE_SPELLING_STACK. */ #define SPELLING_DEPTH() (spelling - spelling_base) #define RESTORE_SPELLING_DEPTH(DEPTH) (spelling = spelling_base + (DEPTH)) /* Push an element on the spelling stack with type KIND and assign VALUE to MEMBER. */ #define PUSH_SPELLING(KIND, VALUE, MEMBER) \ { \ int depth = SPELLING_DEPTH (); \ \ if (depth >= spelling_size) \ { \ spelling_size += 10; \ if (spelling_base == 0) \ spelling_base \ = (struct spelling *) xmalloc (spelling_size * sizeof (struct spelling)); \ else \ spelling_base \ = (struct spelling *) xrealloc (spelling_base, \ spelling_size * sizeof (struct spelling)); \ RESTORE_SPELLING_DEPTH (depth); \ } \ \ spelling->kind = (KIND); \ spelling->MEMBER = (VALUE); \ spelling++; \ } /* Push STRING on the stack. Printed literally. */ static void push_string (string) const char *string; { PUSH_SPELLING (SPELLING_STRING, string, u.s); } /* Push a member name on the stack. Printed as '.' STRING. */ static void push_member_name (decl) tree decl; { const char *const string = DECL_NAME (decl) ? IDENTIFIER_POINTER (DECL_NAME (decl)) : ""; PUSH_SPELLING (SPELLING_MEMBER, string, u.s); } /* Push an array bounds on the stack. Printed as [BOUNDS]. */ static void push_array_bounds (bounds) int bounds; { PUSH_SPELLING (SPELLING_BOUNDS, bounds, u.i); } /* Compute the maximum size in bytes of the printed spelling. */ static int spelling_length () { int size = 0; struct spelling *p; for (p = spelling_base; p < spelling; p++) { if (p->kind == SPELLING_BOUNDS) size += 25; else size += strlen (p->u.s) + 1; } return size; } /* Print the spelling to BUFFER and return it. */ static char * print_spelling (buffer) char *buffer; { char *d = buffer; struct spelling *p; for (p = spelling_base; p < spelling; p++) if (p->kind == SPELLING_BOUNDS) { sprintf (d, "[%d]", p->u.i); d += strlen (d); } else { const char *s; if (p->kind == SPELLING_MEMBER) *d++ = '.'; for (s = p->u.s; (*d = *s++); d++) ; } *d++ = '\0'; return buffer; } /* Issue an error message for a bad initializer component. MSGID identifies the message. The component name is taken from the spelling stack. */ void error_init (msgid) const char *msgid; { char *ofwhat; error ("%s", _(msgid)); ofwhat = print_spelling ((char *) alloca (spelling_length () + 1)); if (*ofwhat) error ("(near initialization for `%s')", ofwhat); } /* Issue a pedantic warning for a bad initializer component. MSGID identifies the message. The component name is taken from the spelling stack. */ void pedwarn_init (msgid) const char *msgid; { char *ofwhat; pedwarn ("%s", _(msgid)); ofwhat = print_spelling ((char *) alloca (spelling_length () + 1)); if (*ofwhat) pedwarn ("(near initialization for `%s')", ofwhat); } /* Issue a warning for a bad initializer component. MSGID identifies the message. The component name is taken from the spelling stack. */ static void warning_init (msgid) const char *msgid; { char *ofwhat; warning ("%s", _(msgid)); ofwhat = print_spelling ((char *) alloca (spelling_length () + 1)); if (*ofwhat) warning ("(near initialization for `%s')", ofwhat); } /* Digest the parser output INIT as an initializer for type TYPE. Return a C expression of type TYPE to represent the initial value. REQUIRE_CONSTANT requests an error if non-constant initializers or elements are seen. */ static tree digest_init (type, init, require_constant) tree type, init; int require_constant; { enum tree_code code = TREE_CODE (type); tree inside_init = init; if (type == error_mark_node || init == error_mark_node || TREE_TYPE (init) == error_mark_node) return error_mark_node; /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */ /* Do not use STRIP_NOPS here. We do not want an enumerator whose value is 0 to count as a null pointer constant. */ if (TREE_CODE (init) == NON_LVALUE_EXPR) inside_init = TREE_OPERAND (init, 0); inside_init = fold (inside_init); /* Initialization of an array of chars from a string constant optionally enclosed in braces. */ if (code == ARRAY_TYPE) { tree typ1 = TYPE_MAIN_VARIANT (TREE_TYPE (type)); if ((typ1 == char_type_node || typ1 == signed_char_type_node || typ1 == unsigned_char_type_node || typ1 == unsigned_wchar_type_node || typ1 == signed_wchar_type_node) && ((inside_init && TREE_CODE (inside_init) == STRING_CST))) { if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)), TYPE_MAIN_VARIANT (type))) return inside_init; if ((TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init))) != char_type_node) && TYPE_PRECISION (typ1) == TYPE_PRECISION (char_type_node)) { error_init ("char-array initialized from wide string"); return error_mark_node; } if ((TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init))) == char_type_node) && TYPE_PRECISION (typ1) != TYPE_PRECISION (char_type_node)) { error_init ("int-array initialized from non-wide string"); return error_mark_node; } TREE_TYPE (inside_init) = type; if (TYPE_DOMAIN (type) != 0 && TYPE_SIZE (type) != 0 && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST /* Subtract 1 (or sizeof (wchar_t)) because it's ok to ignore the terminating null char that is counted in the length of the constant. */ && 0 > compare_tree_int (TYPE_SIZE_UNIT (type), TREE_STRING_LENGTH (inside_init) - ((TYPE_PRECISION (typ1) != TYPE_PRECISION (char_type_node)) ? (TYPE_PRECISION (wchar_type_node) / BITS_PER_UNIT) : 1))) pedwarn_init ("initializer-string for array of chars is too long"); return inside_init; } } /* Any type can be initialized from an expression of the same type, optionally with braces. */ if (inside_init && TREE_TYPE (inside_init) != 0 && (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)), TYPE_MAIN_VARIANT (type)) || (code == ARRAY_TYPE && comptypes (TREE_TYPE (inside_init), type)) || (code == VECTOR_TYPE && comptypes (TREE_TYPE (inside_init), type)) || (code == POINTER_TYPE && (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE || TREE_CODE (TREE_TYPE (inside_init)) == FUNCTION_TYPE) && comptypes (TREE_TYPE (TREE_TYPE (inside_init)), TREE_TYPE (type))))) { if (code == POINTER_TYPE) inside_init = default_function_array_conversion (inside_init); if (require_constant && !flag_isoc99 && TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR) { /* As an extension, allow initializing objects with static storage duration with compound literals (which are then treated just as the brace enclosed list they contain). */ tree decl = COMPOUND_LITERAL_EXPR_DECL (inside_init); inside_init = DECL_INITIAL (decl); } if (code == ARRAY_TYPE && TREE_CODE (inside_init) != STRING_CST && TREE_CODE (inside_init) != CONSTRUCTOR) { error_init ("array initialized from non-constant array expression"); return error_mark_node; } if (optimize && TREE_CODE (inside_init) == VAR_DECL) inside_init = decl_constant_value_for_broken_optimization (inside_init); /* Compound expressions can only occur here if -pedantic or -pedantic-errors is specified. In the later case, we always want an error. In the former case, we simply want a warning. */ if (require_constant && pedantic && TREE_CODE (inside_init) == COMPOUND_EXPR) { inside_init = valid_compound_expr_initializer (inside_init, TREE_TYPE (inside_init)); if (inside_init == error_mark_node) error_init ("initializer element is not constant"); else pedwarn_init ("initializer element is not constant"); if (flag_pedantic_errors) inside_init = error_mark_node; } else if (require_constant && (!TREE_CONSTANT (inside_init) /* This test catches things like `7 / 0' which result in an expression for which TREE_CONSTANT is true, but which is not actually something that is a legal constant. We really should not be using this function, because it is a part of the back-end. Instead, the expression should already have been turned into ERROR_MARK_NODE. */ || !initializer_constant_valid_p (inside_init, TREE_TYPE (inside_init)))) { error_init ("initializer element is not constant"); inside_init = error_mark_node; } return inside_init; } /* Handle scalar types, including conversions. */ if (code == INTEGER_TYPE || code == REAL_TYPE || code == POINTER_TYPE || code == ENUMERAL_TYPE || code == BOOLEAN_TYPE || code == COMPLEX_TYPE) { /* Note that convert_for_assignment calls default_conversion for arrays and functions. We must not call it in the case where inside_init is a null pointer constant. */ inside_init = convert_for_assignment (type, init, _("initialization"), NULL_TREE, NULL_TREE, 0); if (require_constant && ! TREE_CONSTANT (inside_init)) { error_init ("initializer element is not constant"); inside_init = error_mark_node; } else if (require_constant && initializer_constant_valid_p (inside_init, TREE_TYPE (inside_init)) == 0) { error_init ("initializer element is not computable at load time"); inside_init = error_mark_node; } return inside_init; } /* Come here only for records and arrays. */ if (COMPLETE_TYPE_P (type) && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST) { error_init ("variable-sized object may not be initialized"); return error_mark_node; } error_init ("invalid initializer"); return error_mark_node; } /* Handle initializers that use braces. */ /* Type of object we are accumulating a constructor for. This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */ static tree constructor_type; /* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields left to fill. */ static tree constructor_fields; /* For an ARRAY_TYPE, this is the specified index at which to store the next element we get. */ static tree constructor_index; /* For an ARRAY_TYPE, this is the maximum index. */ static tree constructor_max_index; /* For a RECORD_TYPE, this is the first field not yet written out. */ static tree constructor_unfilled_fields; /* For an ARRAY_TYPE, this is the index of the first element not yet written out. */ static tree constructor_unfilled_index; /* In a RECORD_TYPE, the byte index of the next consecutive field. This is so we can generate gaps between fields, when appropriate. */ static tree constructor_bit_index; /* If we are saving up the elements rather than allocating them, this is the list of elements so far (in reverse order, most recent first). */ static tree constructor_elements; /* 1 if constructor should be incrementally stored into a constructor chain, 0 if all the elements should be kept in AVL tree. */ static int constructor_incremental; /* 1 if so far this constructor's elements are all compile-time constants. */ static int constructor_constant; /* 1 if so far this constructor's elements are all valid address constants. */ static int constructor_simple; /* 1 if this constructor is erroneous so far. */ static int constructor_erroneous; /* 1 if have called defer_addressed_constants. */ static int constructor_subconstants_deferred; /* Structure for managing pending initializer elements, organized as an AVL tree. */ struct init_node { struct init_node *left, *right; struct init_node *parent; int balance; tree purpose; tree value; }; /* Tree of pending elements at this constructor level. These are elements encountered out of order which belong at places we haven't reached yet in actually writing the output. Will never hold tree nodes across GC runs. */ static struct init_node *constructor_pending_elts; /* The SPELLING_DEPTH of this constructor. */ static int constructor_depth; /* 0 if implicitly pushing constructor levels is allowed. */ int constructor_no_implicit = 0; /* 0 for C; 1 for some other languages. */ static int require_constant_value; static int require_constant_elements; /* DECL node for which an initializer is being read. 0 means we are reading a constructor expression such as (struct foo) {...}. */ static tree constructor_decl; /* start_init saves the ASMSPEC arg here for really_start_incremental_init. */ static const char *constructor_asmspec; /* Nonzero if this is an initializer for a top-level decl. */ static int constructor_top_level; /* Nonzero if there were any member designators in this initializer. */ static int constructor_designated; /* Nesting depth of designator list. */ static int designator_depth; /* Nonzero if there were diagnosed errors in this designator list. */ static int designator_errorneous; /* This stack has a level for each implicit or explicit level of structuring in the initializer, including the outermost one. It saves the values of most of the variables above. */ struct constructor_range_stack; struct constructor_stack { struct constructor_stack *next; tree type; tree fields; tree index; tree max_index; tree unfilled_index; tree unfilled_fields; tree bit_index; tree elements; struct init_node *pending_elts; int offset; int depth; /* If nonzero, this value should replace the entire constructor at this level. */ tree replacement_value; struct constructor_range_stack *range_stack; char constant; char simple; char implicit; char erroneous; char outer; char incremental; char designated; }; struct constructor_stack *constructor_stack; /* This stack represents designators from some range designator up to the last designator in the list. */ struct constructor_range_stack { struct constructor_range_stack *next, *prev; struct constructor_stack *stack; tree range_start; tree index; tree range_end; tree fields; }; struct constructor_range_stack *constructor_range_stack; /* This stack records separate initializers that are nested. Nested initializers can't happen in ANSI C, but GNU C allows them in cases like { ... (struct foo) { ... } ... }. */ struct initializer_stack { struct initializer_stack *next; tree decl; const char *asmspec; struct constructor_stack *constructor_stack; struct constructor_range_stack *constructor_range_stack; tree elements; struct spelling *spelling; struct spelling *spelling_base; int spelling_size; char top_level; char require_constant_value; char require_constant_elements; char deferred; }; struct initializer_stack *initializer_stack; /* Prepare to parse and output the initializer for variable DECL. */ void start_init (decl, asmspec_tree, top_level) tree decl; tree asmspec_tree; int top_level; { const char *locus; struct initializer_stack *p = (struct initializer_stack *) xmalloc (sizeof (struct initializer_stack)); const char *asmspec = 0; if (asmspec_tree) asmspec = TREE_STRING_POINTER (asmspec_tree); p->decl = constructor_decl; p->asmspec = constructor_asmspec; p->require_constant_value = require_constant_value; p->require_constant_elements = require_constant_elements; p->constructor_stack = constructor_stack; p->constructor_range_stack = constructor_range_stack; p->elements = constructor_elements; p->spelling = spelling; p->spelling_base = spelling_base; p->spelling_size = spelling_size; p->deferred = constructor_subconstants_deferred; p->top_level = constructor_top_level; p->next = initializer_stack; initializer_stack = p; constructor_decl = decl; constructor_asmspec = asmspec; constructor_subconstants_deferred = 0; constructor_designated = 0; constructor_top_level = top_level; if (decl != 0) { require_constant_value = TREE_STATIC (decl); require_constant_elements = ((TREE_STATIC (decl) || (pedantic && !flag_isoc99)) /* For a scalar, you can always use any value to initialize, even within braces. */ && (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE || TREE_CODE (TREE_TYPE (decl)) == RECORD_TYPE || TREE_CODE (TREE_TYPE (decl)) == UNION_TYPE || TREE_CODE (TREE_TYPE (decl)) == QUAL_UNION_TYPE)); locus = IDENTIFIER_POINTER (DECL_NAME (decl)); } else { require_constant_value = 0; require_constant_elements = 0; locus = "(anonymous)"; } constructor_stack = 0; constructor_range_stack = 0; missing_braces_mentioned = 0; spelling_base = 0; spelling_size = 0; RESTORE_SPELLING_DEPTH (0); if (locus) push_string (locus); } void finish_init () { struct initializer_stack *p = initializer_stack; /* Output subconstants (string constants, usually) that were referenced within this initializer and saved up. Must do this if and only if we called defer_addressed_constants. */ if (constructor_subconstants_deferred) output_deferred_addressed_constants (); /* Free the whole constructor stack of this initializer. */ while (constructor_stack) { struct constructor_stack *q = constructor_stack; constructor_stack = q->next; free (q); } if (constructor_range_stack) abort (); /* Pop back to the data of the outer initializer (if any). */ constructor_decl = p->decl; constructor_asmspec = p->asmspec; require_constant_value = p->require_constant_value; require_constant_elements = p->require_constant_elements; constructor_stack = p->constructor_stack; constructor_range_stack = p->constructor_range_stack; constructor_elements = p->elements; spelling = p->spelling; spelling_base = p->spelling_base; spelling_size = p->spelling_size; constructor_subconstants_deferred = p->deferred; constructor_top_level = p->top_level; initializer_stack = p->next; free (p); } /* Call here when we see the initializer is surrounded by braces. This is instead of a call to push_init_level; it is matched by a call to pop_init_level. TYPE is the type to initialize, for a constructor expression. For an initializer for a decl, TYPE is zero. */ void really_start_incremental_init (type) tree type; { struct constructor_stack *p = (struct constructor_stack *) xmalloc (sizeof (struct constructor_stack)); if (type == 0) type = TREE_TYPE (constructor_decl); p->type = constructor_type; p->fields = constructor_fields; p->index = constructor_index; p->max_index = constructor_max_index; p->unfilled_index = constructor_unfilled_index; p->unfilled_fields = constructor_unfilled_fields; p->bit_index = constructor_bit_index; p->elements = constructor_elements; p->constant = constructor_constant; p->simple = constructor_simple; p->erroneous = constructor_erroneous; p->pending_elts = constructor_pending_elts; p->depth = constructor_depth; p->replacement_value = 0; p->implicit = 0; p->range_stack = 0; p->outer = 0; p->incremental = constructor_incremental; p->designated = constructor_designated; p->next = 0; constructor_stack = p; constructor_constant = 1; constructor_simple = 1; constructor_depth = SPELLING_DEPTH (); constructor_elements = 0; constructor_pending_elts = 0; constructor_type = type; constructor_incremental = 1; constructor_designated = 0; designator_depth = 0; designator_errorneous = 0; if (TREE_CODE (constructor_type) == RECORD_TYPE || TREE_CODE (constructor_type) == UNION_TYPE) { constructor_fields = TYPE_FIELDS (constructor_type); /* Skip any nameless bit fields at the beginning. */ while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields) && DECL_NAME (constructor_fields) == 0) constructor_fields = TREE_CHAIN (constructor_fields); constructor_unfilled_fields = constructor_fields; constructor_bit_index = bitsize_zero_node; } else if (TREE_CODE (constructor_type) == ARRAY_TYPE) { if (TYPE_DOMAIN (constructor_type)) { constructor_max_index = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type)); /* Detect non-empty initializations of zero-length arrays. */ if (constructor_max_index == NULL_TREE && TYPE_SIZE (constructor_type)) constructor_max_index = build_int_2 (-1, -1); /* constructor_max_index needs to be an INTEGER_CST. Attempts to initialize VLAs will cause an proper error; avoid tree checking errors as well by setting a safe value. */ if (constructor_max_index && TREE_CODE (constructor_max_index) != INTEGER_CST) constructor_max_index = build_int_2 (-1, -1); constructor_index = convert (bitsizetype, TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type))); } else constructor_index = bitsize_zero_node; constructor_unfilled_index = constructor_index; } else if (TREE_CODE (constructor_type) == VECTOR_TYPE) { /* Vectors are like simple fixed-size arrays. */ constructor_max_index = build_int_2 (TYPE_VECTOR_SUBPARTS (constructor_type) - 1, 0); constructor_index = convert (bitsizetype, bitsize_zero_node); constructor_unfilled_index = constructor_index; } else { /* Handle the case of int x = {5}; */ constructor_fields = constructor_type; constructor_unfilled_fields = constructor_type; } } /* Push down into a subobject, for initialization. If this is for an explicit set of braces, IMPLICIT is 0. If it is because the next element belongs at a lower level, IMPLICIT is 1 (or 2 if the push is because of designator list). */ void push_init_level (implicit) int implicit; { struct constructor_stack *p; tree value = NULL_TREE; /* If we've exhausted any levels that didn't have braces, pop them now. */ while (constructor_stack->implicit) { if ((TREE_CODE (constructor_type) == RECORD_TYPE || TREE_CODE (constructor_type) == UNION_TYPE) && constructor_fields == 0) process_init_element (pop_init_level (1)); else if (TREE_CODE (constructor_type) == ARRAY_TYPE && tree_int_cst_lt (constructor_max_index, constructor_index)) process_init_element (pop_init_level (1)); else break; } /* Unless this is an explicit brace, we need to preserve previous content if any. */ if (implicit) { if ((TREE_CODE (constructor_type) == RECORD_TYPE || TREE_CODE (constructor_type) == UNION_TYPE) && constructor_fields) value = find_init_member (constructor_fields); else if (TREE_CODE (constructor_type) == ARRAY_TYPE) value = find_init_member (constructor_index); } p = (struct constructor_stack *) xmalloc (sizeof (struct constructor_stack)); p->type = constructor_type; p->fields = constructor_fields; p->index = constructor_index; p->max_index = constructor_max_index; p->unfilled_index = constructor_unfilled_index; p->unfilled_fields = constructor_unfilled_fields; p->bit_index = constructor_bit_index; p->elements = constructor_elements; p->constant = constructor_constant; p->simple = constructor_simple; p->erroneous = constructor_erroneous; p->pending_elts = constructor_pending_elts; p->depth = constructor_depth; p->replacement_value = 0; p->implicit = implicit; p->outer = 0; p->incremental = constructor_incremental; p->designated = constructor_designated; p->next = constructor_stack; p->range_stack = 0; constructor_stack = p; constructor_constant = 1; constructor_simple = 1; constructor_depth = SPELLING_DEPTH (); constructor_elements = 0; constructor_incremental = 1; constructor_designated = 0; constructor_pending_elts = 0; if (!implicit) { p->range_stack = constructor_range_stack; constructor_range_stack = 0; designator_depth = 0; designator_errorneous = 0; } /* Don't die if an entire brace-pair level is superfluous in the containing level. */ if (constructor_type == 0) ; else if (TREE_CODE (constructor_type) == RECORD_TYPE || TREE_CODE (constructor_type) == UNION_TYPE) { /* Don't die if there are extra init elts at the end. */ if (constructor_fields == 0) constructor_type = 0; else { constructor_type = TREE_TYPE (constructor_fields); push_member_name (constructor_fields); constructor_depth++; } } else if (TREE_CODE (constructor_type) == ARRAY_TYPE) { constructor_type = TREE_TYPE (constructor_type); push_array_bounds (tree_low_cst (constructor_index, 0)); constructor_depth++; } if (constructor_type == 0) { error_init ("extra brace group at end of initializer"); constructor_fields = 0; constructor_unfilled_fields = 0; return; } if (value && TREE_CODE (value) == CONSTRUCTOR) { constructor_constant = TREE_CONSTANT (value); constructor_simple = TREE_STATIC (value); constructor_elements = TREE_OPERAND (value, 1); if (constructor_elements && (TREE_CODE (constructor_type) == RECORD_TYPE || TREE_CODE (constructor_type) == ARRAY_TYPE)) set_nonincremental_init (); } if (implicit == 1 && warn_missing_braces && !missing_braces_mentioned) { missing_braces_mentioned = 1; warning_init ("missing braces around initializer"); } if (TREE_CODE (constructor_type) == RECORD_TYPE || TREE_CODE (constructor_type) == UNION_TYPE) { constructor_fields = TYPE_FIELDS (constructor_type); /* Skip any nameless bit fields at the beginning. */ while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields) && DECL_NAME (constructor_fields) == 0) constructor_fields = TREE_CHAIN (constructor_fields); constructor_unfilled_fields = constructor_fields; constructor_bit_index = bitsize_zero_node; } else if (TREE_CODE (constructor_type) == VECTOR_TYPE) { /* Vectors are like simple fixed-size arrays. */ constructor_max_index = build_int_2 (TYPE_VECTOR_SUBPARTS (constructor_type) - 1, 0); constructor_index = convert (bitsizetype, integer_zero_node); constructor_unfilled_index = constructor_index; } else if (TREE_CODE (constructor_type) == ARRAY_TYPE) { if (TYPE_DOMAIN (constructor_type)) { constructor_max_index = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type)); /* Detect non-empty initializations of zero-length arrays. */ if (constructor_max_index == NULL_TREE && TYPE_SIZE (constructor_type)) constructor_max_index = build_int_2 (-1, -1); /* constructor_max_index needs to be an INTEGER_CST. Attempts to initialize VLAs will cause an proper error; avoid tree checking errors as well by setting a safe value. */ if (constructor_max_index && TREE_CODE (constructor_max_index) != INTEGER_CST) constructor_max_index = build_int_2 (-1, -1); constructor_index = convert (bitsizetype, TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type))); } else constructor_index = bitsize_zero_node; constructor_unfilled_index = constructor_index; if (value && TREE_CODE (value) == STRING_CST) { /* We need to split the char/wchar array into individual characters, so that we don't have to special case it everywhere. */ set_nonincremental_init_from_string (value); } } else { warning_init ("braces around scalar initializer"); constructor_fields = constructor_type; constructor_unfilled_fields = constructor_type; } } /* At the end of an implicit or explicit brace level, finish up that level of constructor. If we were outputting the elements as they are read, return 0 from inner levels (process_init_element ignores that), but return error_mark_node from the outermost level (that's what we want to put in DECL_INITIAL). Otherwise, return a CONSTRUCTOR expression. */ tree pop_init_level (implicit) int implicit; { struct constructor_stack *p; tree constructor = 0; if (implicit == 0) { /* When we come to an explicit close brace, pop any inner levels that didn't have explicit braces. */ while (constructor_stack->implicit) process_init_element (pop_init_level (1)); if (constructor_range_stack) abort (); } p = constructor_stack; /* Error for initializing a flexible array member, or a zero-length array member in an inappropriate context. */ if (constructor_type && constructor_fields && TREE_CODE (constructor_type) == ARRAY_TYPE && TYPE_DOMAIN (constructor_type) && ! TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type))) { /* Silently discard empty initializations. The parser will already have pedwarned for empty brackets. */ if (integer_zerop (constructor_unfilled_index)) constructor_type = NULL_TREE; else if (! TYPE_SIZE (constructor_type)) { if (constructor_depth > 2) error_init ("initialization of flexible array member in a nested context"); else if (pedantic) pedwarn_init ("initialization of a flexible array member"); /* We have already issued an error message for the existence of a flexible array member not at the end of the structure. Discard the initializer so that we do not abort later. */ if (TREE_CHAIN (constructor_fields) != NULL_TREE) constructor_type = NULL_TREE; } else /* Zero-length arrays are no longer special, so we should no longer get here. */ abort (); } /* Warn when some struct elements are implicitly initialized to zero. */ if (extra_warnings && constructor_type && TREE_CODE (constructor_type) == RECORD_TYPE && constructor_unfilled_fields) { /* Do not warn for flexible array members or zero-length arrays. */ while (constructor_unfilled_fields && (! DECL_SIZE (constructor_unfilled_fields) || integer_zerop (DECL_SIZE (constructor_unfilled_fields)))) constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields); /* Do not warn if this level of the initializer uses member designators; it is likely to be deliberate. */ if (constructor_unfilled_fields && !constructor_designated) { push_member_name (constructor_unfilled_fields); warning_init ("missing initializer"); RESTORE_SPELLING_DEPTH (constructor_depth); } } /* Now output all pending elements. */ constructor_incremental = 1; output_pending_init_elements (1); /* Pad out the end of the structure. */ if (p->replacement_value) /* If this closes a superfluous brace pair, just pass out the element between them. */ constructor = p->replacement_value; else if (constructor_type == 0) ; else if (TREE_CODE (constructor_type) != RECORD_TYPE && TREE_CODE (constructor_type) != UNION_TYPE && TREE_CODE (constructor_type) != ARRAY_TYPE && TREE_CODE (constructor_type) != VECTOR_TYPE) { /* A nonincremental scalar initializer--just return the element, after verifying there is just one. */ if (constructor_elements == 0) { if (!constructor_erroneous) error_init ("empty scalar initializer"); constructor = error_mark_node; } else if (TREE_CHAIN (constructor_elements) != 0) { error_init ("extra elements in scalar initializer"); constructor = TREE_VALUE (constructor_elements); } else constructor = TREE_VALUE (constructor_elements); } else { if (constructor_erroneous) constructor = error_mark_node; else { constructor = build (CONSTRUCTOR, constructor_type, NULL_TREE, nreverse (constructor_elements)); if (constructor_constant) TREE_CONSTANT (constructor) = 1; if (constructor_constant && constructor_simple) TREE_STATIC (constructor) = 1; } } constructor_type = p->type; constructor_fields = p->fields; constructor_index = p->index; constructor_max_index = p->max_index; constructor_unfilled_index = p->unfilled_index; constructor_unfilled_fields = p->unfilled_fields; constructor_bit_index = p->bit_index; constructor_elements = p->elements; constructor_constant = p->constant; constructor_simple = p->simple; constructor_erroneous = p->erroneous; constructor_incremental = p->incremental; constructor_designated = p->designated; constructor_pending_elts = p->pending_elts; constructor_depth = p->depth; if (!p->implicit) constructor_range_stack = p->range_stack; RESTORE_SPELLING_DEPTH (constructor_depth); constructor_stack = p->next; free (p); if (constructor == 0) { if (constructor_stack == 0) return error_mark_node; return NULL_TREE; } return constructor; } /* Common handling for both array range and field name designators. ARRAY argument is nonzero for array ranges. Returns zero for success. */ static int set_designator (array) int array; { tree subtype; enum tree_code subcode; /* Don't die if an entire brace-pair level is superfluous in the containing level. */ if (constructor_type == 0) return 1; /* If there were errors in this designator list already, bail out silently. */ if (designator_errorneous) return 1; if (!designator_depth) { if (constructor_range_stack) abort (); /* Designator list starts at the level of closest explicit braces. */ while (constructor_stack->implicit) process_init_element (pop_init_level (1)); constructor_designated = 1; return 0; } if (constructor_no_implicit) { error_init ("initialization designators may not nest"); return 1; } if (TREE_CODE (constructor_type) == RECORD_TYPE || TREE_CODE (constructor_type) == UNION_TYPE) { subtype = TREE_TYPE (constructor_fields); if (subtype != error_mark_node) subtype = TYPE_MAIN_VARIANT (subtype); } else if (TREE_CODE (constructor_type) == ARRAY_TYPE) { subtype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type)); } else abort (); subcode = TREE_CODE (subtype); if (array && subcode != ARRAY_TYPE) { error_init ("array index in non-array initializer"); return 1; } else if (!array && subcode != RECORD_TYPE && subcode != UNION_TYPE) { error_init ("field name not in record or union initializer"); return 1; } constructor_designated = 1; push_init_level (2); return 0; } /* If there are range designators in designator list, push a new designator to constructor_range_stack. RANGE_END is end of such stack range or NULL_TREE if there is no range designator at this level. */ static void push_range_stack (range_end) tree range_end; { struct constructor_range_stack *p; p = (struct constructor_range_stack *) ggc_alloc (sizeof (struct constructor_range_stack)); p->prev = constructor_range_stack; p->next = 0; p->fields = constructor_fields; p->range_start = constructor_index; p->index = constructor_index; p->stack = constructor_stack; p->range_end = range_end; if (constructor_range_stack) constructor_range_stack->next = p; constructor_range_stack = p; } /* Within an array initializer, specify the next index to be initialized. FIRST is that index. If LAST is nonzero, then initialize a range of indices, running from FIRST through LAST. */ void set_init_index (first, last) tree first, last; { if (set_designator (1)) return; designator_errorneous = 1; while ((TREE_CODE (first) == NOP_EXPR || TREE_CODE (first) == CONVERT_EXPR || TREE_CODE (first) == NON_LVALUE_EXPR) && (TYPE_MODE (TREE_TYPE (first)) == TYPE_MODE (TREE_TYPE (TREE_OPERAND (first, 0))))) first = TREE_OPERAND (first, 0); if (last) while ((TREE_CODE (last) == NOP_EXPR || TREE_CODE (last) == CONVERT_EXPR || TREE_CODE (last) == NON_LVALUE_EXPR) && (TYPE_MODE (TREE_TYPE (last)) == TYPE_MODE (TREE_TYPE (TREE_OPERAND (last, 0))))) last = TREE_OPERAND (last, 0); if (TREE_CODE (first) != INTEGER_CST) error_init ("nonconstant array index in initializer"); else if (last != 0 && TREE_CODE (last) != INTEGER_CST) error_init ("nonconstant array index in initializer"); else if (TREE_CODE (constructor_type) != ARRAY_TYPE) error_init ("array index in non-array initializer"); else if (constructor_max_index && tree_int_cst_lt (constructor_max_index, first)) error_init ("array index in initializer exceeds array bounds"); else { constructor_index = convert (bitsizetype, first); if (last) { if (tree_int_cst_equal (first, last)) last = 0; else if (tree_int_cst_lt (last, first)) { error_init ("empty index range in initializer"); last = 0; } else { last = convert (bitsizetype, last); if (constructor_max_index != 0 && tree_int_cst_lt (constructor_max_index, last)) { error_init ("array index range in initializer exceeds array bounds"); last = 0; } } } designator_depth++; designator_errorneous = 0; if (constructor_range_stack || last) push_range_stack (last); } } /* Within a struct initializer, specify the next field to be initialized. */ void set_init_label (fieldname) tree fieldname; { tree tail; if (set_designator (0)) return; designator_errorneous = 1; if (TREE_CODE (constructor_type) != RECORD_TYPE && TREE_CODE (constructor_type) != UNION_TYPE) { error_init ("field name not in record or union initializer"); return; } for (tail = TYPE_FIELDS (constructor_type); tail; tail = TREE_CHAIN (tail)) { if (DECL_NAME (tail) == fieldname) break; } if (tail == 0) error ("unknown field `%s' specified in initializer", IDENTIFIER_POINTER (fieldname)); else { constructor_fields = tail; designator_depth++; designator_errorneous = 0; if (constructor_range_stack) push_range_stack (NULL_TREE); } } /* Add a new initializer to the tree of pending initializers. PURPOSE identifies the initializer, either array index or field in a structure. VALUE is the value of that index or field. */ static void add_pending_init (purpose, value) tree purpose, value; { struct init_node *p, **q, *r; q = &constructor_pending_elts; p = 0; if (TREE_CODE (constructor_type) == ARRAY_TYPE) { while (*q != 0) { p = *q; if (tree_int_cst_lt (purpose, p->purpose)) q = &p->left; else if (tree_int_cst_lt (p->purpose, purpose)) q = &p->right; else { if (TREE_SIDE_EFFECTS (p->value)) warning_init ("initialized field with side-effects overwritten"); p->value = value; return; } } } else { tree bitpos; bitpos = bit_position (purpose); while (*q != NULL) { p = *q; if (tree_int_cst_lt (bitpos, bit_position (p->purpose))) q = &p->left; else if (p->purpose != purpose) q = &p->right; else { if (TREE_SIDE_EFFECTS (p->value)) warning_init ("initialized field with side-effects overwritten"); p->value = value; return; } } } r = (struct init_node *) ggc_alloc (sizeof (struct init_node)); r->purpose = purpose; r->value = value; *q = r; r->parent = p; r->left = 0; r->right = 0; r->balance = 0; while (p) { struct init_node *s; if (r == p->left) { if (p->balance == 0) p->balance = -1; else if (p->balance < 0) { if (r->balance < 0) { /* L rotation. */ p->left = r->right; if (p->left) p->left->parent = p; r->right = p; p->balance = 0; r->balance = 0; s = p->parent; p->parent = r; r->parent = s; if (s) { if (s->left == p) s->left = r; else s->right = r; } else constructor_pending_elts = r; } else { /* LR rotation. */ struct init_node *t = r->right; r->right = t->left; if (r->right) r->right->parent = r; t->left = r; p->left = t->right; if (p->left) p->left->parent = p; t->right = p; p->balance = t->balance < 0; r->balance = -(t->balance > 0); t->balance = 0; s = p->parent; p->parent = t; r->parent = t; t->parent = s; if (s) { if (s->left == p) s->left = t; else s->right = t; } else constructor_pending_elts = t; } break; } else { /* p->balance == +1; growth of left side balances the node. */ p->balance = 0; break; } } else /* r == p->right */ { if (p->balance == 0) /* Growth propagation from right side. */ p->balance++; else if (p->balance > 0) { if (r->balance > 0) { /* R rotation. */ p->right = r->left; if (p->right) p->right->parent = p; r->left = p; p->balance = 0; r->balance = 0; s = p->parent; p->parent = r; r->parent = s; if (s) { if (s->left == p) s->left = r; else s->right = r; } else constructor_pending_elts = r; } else /* r->balance == -1 */ { /* RL rotation */ struct init_node *t = r->left; r->left = t->right; if (r->left) r->left->parent = r; t->right = r; p->right = t->left; if (p->right) p->right->parent = p; t->left = p; r->balance = (t->balance < 0); p->balance = -(t->balance > 0); t->balance = 0; s = p->parent; p->parent = t; r->parent = t; t->parent = s; if (s) { if (s->left == p) s->left = t; else s->right = t; } else constructor_pending_elts = t; } break; } else { /* p->balance == -1; growth of right side balances the node. */ p->balance = 0; break; } } r = p; p = p->parent; } } /* Build AVL tree from a sorted chain. */ static void set_nonincremental_init () { tree chain; if (TREE_CODE (constructor_type) != RECORD_TYPE && TREE_CODE (constructor_type) != ARRAY_TYPE) return; for (chain = constructor_elements; chain; chain = TREE_CHAIN (chain)) add_pending_init (TREE_PURPOSE (chain), TREE_VALUE (chain)); constructor_elements = 0; if (TREE_CODE (constructor_type) == RECORD_TYPE) { constructor_unfilled_fields = TYPE_FIELDS (constructor_type); /* Skip any nameless bit fields at the beginning. */ while (constructor_unfilled_fields != 0 && DECL_C_BIT_FIELD (constructor_unfilled_fields) && DECL_NAME (constructor_unfilled_fields) == 0) constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields); } else if (TREE_CODE (constructor_type) == ARRAY_TYPE) { if (TYPE_DOMAIN (constructor_type)) constructor_unfilled_index = convert (bitsizetype, TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type))); else constructor_unfilled_index = bitsize_zero_node; } constructor_incremental = 0; } /* Build AVL tree from a string constant. */ static void set_nonincremental_init_from_string (str) tree str; { tree value, purpose, type; HOST_WIDE_INT val[2]; const char *p, *end; int byte, wchar_bytes, charwidth, bitpos; if (TREE_CODE (constructor_type) != ARRAY_TYPE) abort (); if (TYPE_PRECISION (TREE_TYPE (TREE_TYPE (str))) == TYPE_PRECISION (char_type_node)) wchar_bytes = 1; else if (TYPE_PRECISION (TREE_TYPE (TREE_TYPE (str))) == TYPE_PRECISION (wchar_type_node)) wchar_bytes = TYPE_PRECISION (wchar_type_node) / BITS_PER_UNIT; else abort (); charwidth = TYPE_PRECISION (char_type_node); type = TREE_TYPE (constructor_type); p = TREE_STRING_POINTER (str); end = p + TREE_STRING_LENGTH (str); for (purpose = bitsize_zero_node; p < end && !tree_int_cst_lt (constructor_max_index, purpose); purpose = size_binop (PLUS_EXPR, purpose, bitsize_one_node)) { if (wchar_bytes == 1) { val[1] = (unsigned char) *p++; val[0] = 0; } else { val[0] = 0; val[1] = 0; for (byte = 0; byte < wchar_bytes; byte++) { if (BYTES_BIG_ENDIAN) bitpos = (wchar_bytes - byte - 1) * charwidth; else bitpos = byte * charwidth; val[bitpos < HOST_BITS_PER_WIDE_INT] |= ((unsigned HOST_WIDE_INT) ((unsigned char) *p++)) << (bitpos % HOST_BITS_PER_WIDE_INT); } } if (!TREE_UNSIGNED (type)) { bitpos = ((wchar_bytes - 1) * charwidth) + HOST_BITS_PER_CHAR; if (bitpos < HOST_BITS_PER_WIDE_INT) { if (val[1] & (((HOST_WIDE_INT) 1) << (bitpos - 1))) { val[1] |= ((HOST_WIDE_INT) -1) << bitpos; val[0] = -1; } } else if (bitpos == HOST_BITS_PER_WIDE_INT) { if (val[1] < 0) val[0] = -1; } else if (val[0] & (((HOST_WIDE_INT) 1) << (bitpos - 1 - HOST_BITS_PER_WIDE_INT))) val[0] |= ((HOST_WIDE_INT) -1) << (bitpos - HOST_BITS_PER_WIDE_INT); } value = build_int_2 (val[1], val[0]); TREE_TYPE (value) = type; add_pending_init (purpose, value); } constructor_incremental = 0; } /* Return value of FIELD in pending initializer or zero if the field was not initialized yet. */ static tree find_init_member (field) tree field; { struct init_node *p; if (TREE_CODE (constructor_type) == ARRAY_TYPE) { if (constructor_incremental && tree_int_cst_lt (field, constructor_unfilled_index)) set_nonincremental_init (); p = constructor_pending_elts; while (p) { if (tree_int_cst_lt (field, p->purpose)) p = p->left; else if (tree_int_cst_lt (p->purpose, field)) p = p->right; else return p->value; } } else if (TREE_CODE (constructor_type) == RECORD_TYPE) { tree bitpos = bit_position (field); if (constructor_incremental && (!constructor_unfilled_fields || tree_int_cst_lt (bitpos, bit_position (constructor_unfilled_fields)))) set_nonincremental_init (); p = constructor_pending_elts; while (p) { if (field == p->purpose) return p->value; else if (tree_int_cst_lt (bitpos, bit_position (p->purpose))) p = p->left; else p = p->right; } } else if (TREE_CODE (constructor_type) == UNION_TYPE) { if (constructor_elements && TREE_PURPOSE (constructor_elements) == field) return TREE_VALUE (constructor_elements); } return 0; } /* "Output" the next constructor element. At top level, really output it to assembler code now. Otherwise, collect it in a list from which we will make a CONSTRUCTOR. TYPE is the data type that the containing data type wants here. FIELD is the field (a FIELD_DECL) or the index that this element fills. PENDING if non-nil means output pending elements that belong right after this element. (PENDING is normally 1; it is 0 while outputting pending elements, to avoid recursion.) */ static void output_init_element (value, type, field, pending) tree value, type, field; int pending; { if (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE || (TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE && !(TREE_CODE (value) == STRING_CST && TREE_CODE (type) == ARRAY_TYPE && TREE_CODE (TREE_TYPE (type)) == INTEGER_TYPE) && !comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (value)), TYPE_MAIN_VARIANT (type)))) value = default_conversion (value); if (TREE_CODE (value) == COMPOUND_LITERAL_EXPR && require_constant_value && !flag_isoc99 && pending) { /* As an extension, allow initializing objects with static storage duration with compound literals (which are then treated just as the brace enclosed list they contain). */ tree decl = COMPOUND_LITERAL_EXPR_DECL (value); value = DECL_INITIAL (decl); } if (value == error_mark_node) constructor_erroneous = 1; else if (!TREE_CONSTANT (value)) constructor_constant = 0; else if (initializer_constant_valid_p (value, TREE_TYPE (value)) == 0 || ((TREE_CODE (constructor_type) == RECORD_TYPE || TREE_CODE (constructor_type) == UNION_TYPE) && DECL_C_BIT_FIELD (field) && TREE_CODE (value) != INTEGER_CST)) constructor_simple = 0; if (require_constant_value && ! TREE_CONSTANT (value)) { error_init ("initializer element is not constant"); value = error_mark_node; } else if (require_constant_elements && initializer_constant_valid_p (value, TREE_TYPE (value)) == 0) pedwarn ("initializer element is not computable at load time"); /* If this field is empty (and not at the end of structure), don't do anything other than checking the initializer. */ if (field && (TREE_TYPE (field) == error_mark_node || (COMPLETE_TYPE_P (TREE_TYPE (field)) && integer_zerop (TYPE_SIZE (TREE_TYPE (field))) && (TREE_CODE (constructor_type) == ARRAY_TYPE || TREE_CHAIN (field))))) return; value = digest_init (type, value, require_constant_value); if (value == error_mark_node) { constructor_erroneous = 1; return; } /* If this element doesn't come next in sequence, put it on constructor_pending_elts. */ if (TREE_CODE (constructor_type) == ARRAY_TYPE && (!constructor_incremental || !tree_int_cst_equal (field, constructor_unfilled_index))) { if (constructor_incremental && tree_int_cst_lt (field, constructor_unfilled_index)) set_nonincremental_init (); add_pending_init (field, value); return; } else if (TREE_CODE (constructor_type) == RECORD_TYPE && (!constructor_incremental || field != constructor_unfilled_fields)) { /* We do this for records but not for unions. In a union, no matter which field is specified, it can be initialized right away since it starts at the beginning of the union. */ if (constructor_incremental) { if (!constructor_unfilled_fields) set_nonincremental_init (); else { tree bitpos, unfillpos; bitpos = bit_position (field); unfillpos = bit_position (constructor_unfilled_fields); if (tree_int_cst_lt (bitpos, unfillpos)) set_nonincremental_init (); } } add_pending_init (field, value); return; } else if (TREE_CODE (constructor_type) == UNION_TYPE && constructor_elements) { if (TREE_SIDE_EFFECTS (TREE_VALUE (constructor_elements))) warning_init ("initialized field with side-effects overwritten"); /* We can have just one union field set. */ constructor_elements = 0; } /* Otherwise, output this element either to constructor_elements or to the assembler file. */ if (field && TREE_CODE (field) == INTEGER_CST) field = copy_node (field); constructor_elements = tree_cons (field, value, constructor_elements); /* Advance the variable that indicates sequential elements output. */ if (TREE_CODE (constructor_type) == ARRAY_TYPE) constructor_unfilled_index = size_binop (PLUS_EXPR, constructor_unfilled_index, bitsize_one_node); else if (TREE_CODE (constructor_type) == RECORD_TYPE) { constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields); /* Skip any nameless bit fields. */ while (constructor_unfilled_fields != 0 && DECL_C_BIT_FIELD (constructor_unfilled_fields) && DECL_NAME (constructor_unfilled_fields) == 0) constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields); } else if (TREE_CODE (constructor_type) == UNION_TYPE) constructor_unfilled_fields = 0; /* Now output any pending elements which have become next. */ if (pending) output_pending_init_elements (0); } /* Output any pending elements which have become next. As we output elements, constructor_unfilled_{fields,index} advances, which may cause other elements to become next; if so, they too are output. If ALL is 0, we return when there are no more pending elements to output now. If ALL is 1, we output space as necessary so that we can output all the pending elements. */ static void output_pending_init_elements (all) int all; { struct init_node *elt = constructor_pending_elts; tree next; retry: /* Look thru the whole pending tree. If we find an element that should be output now, output it. Otherwise, set NEXT to the element that comes first among those still pending. */ next = 0; while (elt) { if (TREE_CODE (constructor_type) == ARRAY_TYPE) { if (tree_int_cst_equal (elt->purpose, constructor_unfilled_index)) output_init_element (elt->value, TREE_TYPE (constructor_type), constructor_unfilled_index, 0); else if (tree_int_cst_lt (constructor_unfilled_index, elt->purpose)) { /* Advance to the next smaller node. */ if (elt->left) elt = elt->left; else { /* We have reached the smallest node bigger than the current unfilled index. Fill the space first. */ next = elt->purpose; break; } } else { /* Advance to the next bigger node. */ if (elt->right) elt = elt->right; else { /* We have reached the biggest node in a subtree. Find the parent of it, which is the next bigger node. */ while (elt->parent && elt->parent->right == elt) elt = elt->parent; elt = elt->parent; if (elt && tree_int_cst_lt (constructor_unfilled_index, elt->purpose)) { next = elt->purpose; break; } } } } else if (TREE_CODE (constructor_type) == RECORD_TYPE || TREE_CODE (constructor_type) == UNION_TYPE) { tree ctor_unfilled_bitpos, elt_bitpos; /* If the current record is complete we are done. */ if (constructor_unfilled_fields == 0) break; ctor_unfilled_bitpos = bit_position (constructor_unfilled_fields); elt_bitpos = bit_position (elt->purpose); /* We can't compare fields here because there might be empty fields in between. */ if (tree_int_cst_equal (elt_bitpos, ctor_unfilled_bitpos)) { constructor_unfilled_fields = elt->purpose; output_init_element (elt->value, TREE_TYPE (elt->purpose), elt->purpose, 0); } else if (tree_int_cst_lt (ctor_unfilled_bitpos, elt_bitpos)) { /* Advance to the next smaller node. */ if (elt->left) elt = elt->left; else { /* We have reached the smallest node bigger than the current unfilled field. Fill the space first. */ next = elt->purpose; break; } } else { /* Advance to the next bigger node. */ if (elt->right) elt = elt->right; else { /* We have reached the biggest node in a subtree. Find the parent of it, which is the next bigger node. */ while (elt->parent && elt->parent->right == elt) elt = elt->parent; elt = elt->parent; if (elt && (tree_int_cst_lt (ctor_unfilled_bitpos, bit_position (elt->purpose)))) { next = elt->purpose; break; } } } } } /* Ordinarily return, but not if we want to output all and there are elements left. */ if (! (all && next != 0)) return; /* If it's not incremental, just skip over the gap, so that after jumping to retry we will output the next successive element. */ if (TREE_CODE (constructor_type) == RECORD_TYPE || TREE_CODE (constructor_type) == UNION_TYPE) constructor_unfilled_fields = next; else if (TREE_CODE (constructor_type) == ARRAY_TYPE) constructor_unfilled_index = next; /* ELT now points to the node in the pending tree with the next initializer to output. */ goto retry; } /* Add one non-braced element to the current constructor level. This adjusts the current position within the constructor's type. This may also start or terminate implicit levels to handle a partly-braced initializer. Once this has found the correct level for the new element, it calls output_init_element. */ void process_init_element (value) tree value; { tree orig_value = value; int string_flag = value != 0 && TREE_CODE (value) == STRING_CST; designator_depth = 0; designator_errorneous = 0; /* Handle superfluous braces around string cst as in char x[] = {"foo"}; */ if (string_flag && constructor_type && TREE_CODE (constructor_type) == ARRAY_TYPE && TREE_CODE (TREE_TYPE (constructor_type)) == INTEGER_TYPE && integer_zerop (constructor_unfilled_index)) { if (constructor_stack->replacement_value) error_init ("excess elements in char array initializer"); constructor_stack->replacement_value = value; return; } if (constructor_stack->replacement_value != 0) { error_init ("excess elements in struct initializer"); return; } /* Ignore elements of a brace group if it is entirely superfluous and has already been diagnosed. */ if (constructor_type == 0) return; /* If we've exhausted any levels that didn't have braces, pop them now. */ while (constructor_stack->implicit) { if ((TREE_CODE (constructor_type) == RECORD_TYPE || TREE_CODE (constructor_type) == UNION_TYPE) && constructor_fields == 0) process_init_element (pop_init_level (1)); else if (TREE_CODE (constructor_type) == ARRAY_TYPE && (constructor_max_index == 0 || tree_int_cst_lt (constructor_max_index, constructor_index))) process_init_element (pop_init_level (1)); else break; } /* In the case of [LO ... HI] = VALUE, only evaluate VALUE once. */ if (constructor_range_stack) { /* If value is a compound literal and we'll be just using its content, don't put it into a SAVE_EXPR. */ if (TREE_CODE (value) != COMPOUND_LITERAL_EXPR || !require_constant_value || flag_isoc99) value = save_expr (value); } while (1) { if (TREE_CODE (constructor_type) == RECORD_TYPE) { tree fieldtype; enum tree_code fieldcode; if (constructor_fields == 0) { pedwarn_init ("excess elements in struct initializer"); break; } fieldtype = TREE_TYPE (constructor_fields); if (fieldtype != error_mark_node) fieldtype = TYPE_MAIN_VARIANT (fieldtype); fieldcode = TREE_CODE (fieldtype); /* Error for non-static initialization of a flexible array member. */ if (fieldcode == ARRAY_TYPE && !require_constant_value && TYPE_SIZE (fieldtype) == NULL_TREE && TREE_CHAIN (constructor_fields) == NULL_TREE) { error_init ("non-static initialization of a flexible array member"); break; } /* Accept a string constant to initialize a subarray. */ if (value != 0 && fieldcode == ARRAY_TYPE && TREE_CODE (TREE_TYPE (fieldtype)) == INTEGER_TYPE && string_flag) value = orig_value; /* Otherwise, if we have come to a subaggregate, and we don't have an element of its type, push into it. */ else if (value != 0 && !constructor_no_implicit && value != error_mark_node && TYPE_MAIN_VARIANT (TREE_TYPE (value)) != fieldtype && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE || fieldcode == UNION_TYPE)) { push_init_level (1); continue; } if (value) { push_member_name (constructor_fields); output_init_element (value, fieldtype, constructor_fields, 1); RESTORE_SPELLING_DEPTH (constructor_depth); } else /* Do the bookkeeping for an element that was directly output as a constructor. */ { /* For a record, keep track of end position of last field. */ if (DECL_SIZE (constructor_fields)) constructor_bit_index = size_binop (PLUS_EXPR, bit_position (constructor_fields), DECL_SIZE (constructor_fields)); constructor_unfilled_fields = TREE_CHAIN (constructor_fields); /* Skip any nameless bit fields. */ while (constructor_unfilled_fields != 0 && DECL_C_BIT_FIELD (constructor_unfilled_fields) && DECL_NAME (constructor_unfilled_fields) == 0) constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields); } constructor_fields = TREE_CHAIN (constructor_fields); /* Skip any nameless bit fields at the beginning. */ while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields) && DECL_NAME (constructor_fields) == 0) constructor_fields = TREE_CHAIN (constructor_fields); } else if (TREE_CODE (constructor_type) == UNION_TYPE) { tree fieldtype; enum tree_code fieldcode; if (constructor_fields == 0) { pedwarn_init ("excess elements in union initializer"); break; } fieldtype = TREE_TYPE (constructor_fields); if (fieldtype != error_mark_node) fieldtype = TYPE_MAIN_VARIANT (fieldtype); fieldcode = TREE_CODE (fieldtype); /* Warn that traditional C rejects initialization of unions. We skip the warning if the value is zero. This is done under the assumption that the zero initializer in user code appears conditioned on e.g. __STDC__ to avoid "missing initializer" warnings and relies on default initialization to zero in the traditional C case. We also skip the warning if the initializer is designated, again on the assumption that this must be conditional on __STDC__ anyway (and we've already complained about the member-designator already). */ if (warn_traditional && !in_system_header && !constructor_designated && !(value && (integer_zerop (value) || real_zerop (value)))) warning ("traditional C rejects initialization of unions"); /* Accept a string constant to initialize a subarray. */ if (value != 0 && fieldcode == ARRAY_TYPE && TREE_CODE (TREE_TYPE (fieldtype)) == INTEGER_TYPE && string_flag) value = orig_value; /* Otherwise, if we have come to a subaggregate, and we don't have an element of its type, push into it. */ else if (value != 0 && !constructor_no_implicit && value != error_mark_node && TYPE_MAIN_VARIANT (TREE_TYPE (value)) != fieldtype && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE || fieldcode == UNION_TYPE)) { push_init_level (1); continue; } if (value) { push_member_name (constructor_fields); output_init_element (value, fieldtype, constructor_fields, 1); RESTORE_SPELLING_DEPTH (constructor_depth); } else /* Do the bookkeeping for an element that was directly output as a constructor. */ { constructor_bit_index = DECL_SIZE (constructor_fields); constructor_unfilled_fields = TREE_CHAIN (constructor_fields); } constructor_fields = 0; } else if (TREE_CODE (constructor_type) == ARRAY_TYPE) { tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type)); enum tree_code eltcode = TREE_CODE (elttype); /* Accept a string constant to initialize a subarray. */ if (value != 0 && eltcode == ARRAY_TYPE && TREE_CODE (TREE_TYPE (elttype)) == INTEGER_TYPE && string_flag) value = orig_value; /* Otherwise, if we have come to a subaggregate, and we don't have an element of its type, push into it. */ else if (value != 0 && !constructor_no_implicit && value != error_mark_node && TYPE_MAIN_VARIANT (TREE_TYPE (value)) != elttype && (eltcode == RECORD_TYPE || eltcode == ARRAY_TYPE || eltcode == UNION_TYPE)) { push_init_level (1); continue; } if (constructor_max_index != 0 && (tree_int_cst_lt (constructor_max_index, constructor_index) || integer_all_onesp (constructor_max_index))) { pedwarn_init ("excess elements in array initializer"); break; } /* Now output the actual element. */ if (value) { push_array_bounds (tree_low_cst (constructor_index, 0)); output_init_element (value, elttype, constructor_index, 1); RESTORE_SPELLING_DEPTH (constructor_depth); } constructor_index = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node); if (! value) /* If we are doing the bookkeeping for an element that was directly output as a constructor, we must update constructor_unfilled_index. */ constructor_unfilled_index = constructor_index; } else if (TREE_CODE (constructor_type) == VECTOR_TYPE) { tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type)); /* Do a basic check of initializer size. Note that vectors always have a fixed size derived from their type. */ if (tree_int_cst_lt (constructor_max_index, constructor_index)) { pedwarn_init ("excess elements in vector initializer"); break; } /* Now output the actual element. */ if (value) output_init_element (value, elttype, constructor_index, 1); constructor_index = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node); if (! value) /* If we are doing the bookkeeping for an element that was directly output as a constructor, we must update constructor_unfilled_index. */ constructor_unfilled_index = constructor_index; } /* Handle the sole element allowed in a braced initializer for a scalar variable. */ else if (constructor_fields == 0) { pedwarn_init ("excess elements in scalar initializer"); break; } else { if (value) output_init_element (value, constructor_type, NULL_TREE, 1); constructor_fields = 0; } /* Handle range initializers either at this level or anywhere higher in the designator stack. */ if (constructor_range_stack) { struct constructor_range_stack *p, *range_stack; int finish = 0; range_stack = constructor_range_stack; constructor_range_stack = 0; while (constructor_stack != range_stack->stack) { if (!constructor_stack->implicit) abort (); process_init_element (pop_init_level (1)); } for (p = range_stack; !p->range_end || tree_int_cst_equal (p->index, p->range_end); p = p->prev) { if (!constructor_stack->implicit) abort (); process_init_element (pop_init_level (1)); } p->index = size_binop (PLUS_EXPR, p->index, bitsize_one_node); if (tree_int_cst_equal (p->index, p->range_end) && !p->prev) finish = 1; while (1) { constructor_index = p->index; constructor_fields = p->fields; if (finish && p->range_end && p->index == p->range_start) { finish = 0; p->prev = 0; } p = p->next; if (!p) break; push_init_level (2); p->stack = constructor_stack; if (p->range_end && tree_int_cst_equal (p->index, p->range_end)) p->index = p->range_start; } if (!finish) constructor_range_stack = range_stack; continue; } break; } constructor_range_stack = 0; } /* Build a simple asm-statement, from one string literal. */ tree simple_asm_stmt (expr) tree expr; { STRIP_NOPS (expr); if (TREE_CODE (expr) == ADDR_EXPR) expr = TREE_OPERAND (expr, 0); if (TREE_CODE (expr) == STRING_CST) { tree stmt; stmt = add_stmt (build_stmt (ASM_STMT, NULL_TREE, expr, NULL_TREE, NULL_TREE, NULL_TREE)); ASM_INPUT_P (stmt) = 1; return stmt; } error ("argument of `asm' is not a constant string"); return NULL_TREE; } /* Build an asm-statement, whose components are a CV_QUALIFIER, a STRING, some OUTPUTS, some INPUTS, and some CLOBBERS. */ tree build_asm_stmt (cv_qualifier, string, outputs, inputs, clobbers) tree cv_qualifier; tree string; tree outputs; tree inputs; tree clobbers; { tree tail; if (TREE_CODE (string) != STRING_CST) { error ("asm template is not a string constant"); return NULL_TREE; } if (cv_qualifier != NULL_TREE && cv_qualifier != ridpointers[(int) RID_VOLATILE]) { warning ("%s qualifier ignored on asm", IDENTIFIER_POINTER (cv_qualifier)); cv_qualifier = NULL_TREE; } /* We can remove output conversions that change the type, but not the mode. */ for (tail = outputs; tail; tail = TREE_CHAIN (tail)) { tree output = TREE_VALUE (tail); STRIP_NOPS (output); TREE_VALUE (tail) = output; /* Allow conversions as LHS here. build_modify_expr as called below will do the right thing with them. */ while (TREE_CODE (output) == NOP_EXPR || TREE_CODE (output) == CONVERT_EXPR || TREE_CODE (output) == FLOAT_EXPR || TREE_CODE (output) == FIX_TRUNC_EXPR || TREE_CODE (output) == FIX_FLOOR_EXPR || TREE_CODE (output) == FIX_ROUND_EXPR || TREE_CODE (output) == FIX_CEIL_EXPR) output = TREE_OPERAND (output, 0); lvalue_or_else (TREE_VALUE (tail), "invalid lvalue in asm statement"); } /* Remove output conversions that change the type but not the mode. */ for (tail = outputs; tail; tail = TREE_CHAIN (tail)) { tree output = TREE_VALUE (tail); STRIP_NOPS (output); TREE_VALUE (tail) = output; } /* Perform default conversions on array and function inputs. Don't do this for other types as it would screw up operands expected to be in memory. */ for (tail = inputs; tail; tail = TREE_CHAIN (tail)) TREE_VALUE (tail) = default_function_array_conversion (TREE_VALUE (tail)); return add_stmt (build_stmt (ASM_STMT, cv_qualifier, string, outputs, inputs, clobbers)); } /* Expand an ASM statement with operands, handling output operands that are not variables or INDIRECT_REFS by transforming such cases into cases that expand_asm_operands can handle. Arguments are same as for expand_asm_operands. */ void c_expand_asm_operands (string, outputs, inputs, clobbers, vol, filename, line) tree string, outputs, inputs, clobbers; int vol; const char *filename; int line; { int noutputs = list_length (outputs); int i; /* o[I] is the place that output number I should be written. */ tree *o = (tree *) alloca (noutputs * sizeof (tree)); tree tail; /* Record the contents of OUTPUTS before it is modified. */ for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++) { o[i] = TREE_VALUE (tail); if (o[i] == error_mark_node) return; } /* Generate the ASM_OPERANDS insn; store into the TREE_VALUEs of OUTPUTS some trees for where the values were actually stored. */ expand_asm_operands (string, outputs, inputs, clobbers, vol, filename, line); /* Copy all the intermediate outputs into the specified outputs. */ for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++) { if (o[i] != TREE_VALUE (tail)) { expand_expr (build_modify_expr (o[i], NOP_EXPR, TREE_VALUE (tail)), NULL_RTX, VOIDmode, EXPAND_NORMAL); free_temp_slots (); /* Restore the original value so that it's correct the next time we expand this function. */ TREE_VALUE (tail) = o[i]; } /* Detect modification of read-only values. (Otherwise done by build_modify_expr.) */ else { tree type = TREE_TYPE (o[i]); if (TREE_READONLY (o[i]) || TYPE_READONLY (type) || ((TREE_CODE (type) == RECORD_TYPE || TREE_CODE (type) == UNION_TYPE) && C_TYPE_FIELDS_READONLY (type))) readonly_warning (o[i], "modification by `asm'"); } } /* Those MODIFY_EXPRs could do autoincrements. */ emit_queue (); } /* Expand a C `return' statement. RETVAL is the expression for what to return, or a null pointer for `return;' with no value. */ tree c_expand_return (retval) tree retval; { tree valtype = TREE_TYPE (TREE_TYPE (current_function_decl)); if (TREE_THIS_VOLATILE (current_function_decl)) warning ("function declared `noreturn' has a `return' statement"); if (!retval) { current_function_returns_null = 1; if ((warn_return_type || flag_isoc99) && valtype != 0 && TREE_CODE (valtype) != VOID_TYPE) pedwarn_c99 ("`return' with no value, in function returning non-void"); } else if (valtype == 0 || TREE_CODE (valtype) == VOID_TYPE) { current_function_returns_null = 1; if (pedantic || TREE_CODE (TREE_TYPE (retval)) != VOID_TYPE) pedwarn ("`return' with a value, in function returning void"); } else { tree t = convert_for_assignment (valtype, retval, _("return"), NULL_TREE, NULL_TREE, 0); tree res = DECL_RESULT (current_function_decl); tree inner; current_function_returns_value = 1; if (t == error_mark_node) return NULL_TREE; inner = t = convert (TREE_TYPE (res), t); /* Strip any conversions, additions, and subtractions, and see if we are returning the address of a local variable. Warn if so. */ while (1) { switch (TREE_CODE (inner)) { case NOP_EXPR: case NON_LVALUE_EXPR: case CONVERT_EXPR: case PLUS_EXPR: inner = TREE_OPERAND (inner, 0); continue; case MINUS_EXPR: /* If the second operand of the MINUS_EXPR has a pointer type (or is converted from it), this may be valid, so don't give a warning. */ { tree op1 = TREE_OPERAND (inner, 1); while (! POINTER_TYPE_P (TREE_TYPE (op1)) && (TREE_CODE (op1) == NOP_EXPR || TREE_CODE (op1) == NON_LVALUE_EXPR || TREE_CODE (op1) == CONVERT_EXPR)) op1 = TREE_OPERAND (op1, 0); if (POINTER_TYPE_P (TREE_TYPE (op1))) break; inner = TREE_OPERAND (inner, 0); continue; } case ADDR_EXPR: inner = TREE_OPERAND (inner, 0); while (TREE_CODE_CLASS (TREE_CODE (inner)) == 'r') inner = TREE_OPERAND (inner, 0); if (TREE_CODE (inner) == VAR_DECL && ! DECL_EXTERNAL (inner) && ! TREE_STATIC (inner) && DECL_CONTEXT (inner) == current_function_decl) warning ("function returns address of local variable"); break; default: break; } break; } retval = build (MODIFY_EXPR, TREE_TYPE (res), res, t); } return add_stmt (build_return_stmt (retval)); } struct c_switch { /* The SWITCH_STMT being built. */ tree switch_stmt; /* A splay-tree mapping the low element of a case range to the high element, or NULL_TREE if there is no high element. Used to determine whether or not a new case label duplicates an old case label. We need a tree, rather than simply a hash table, because of the GNU case range extension. */ splay_tree cases; /* The next node on the stack. */ struct c_switch *next; }; /* A stack of the currently active switch statements. The innermost switch statement is on the top of the stack. There is no need to mark the stack for garbage collection because it is only active during the processing of the body of a function, and we never collect at that point. */ static struct c_switch *switch_stack; /* Start a C switch statement, testing expression EXP. Return the new SWITCH_STMT. */ tree c_start_case (exp) tree exp; { enum tree_code code; tree type, orig_type = error_mark_node; struct c_switch *cs; if (exp != error_mark_node) { code = TREE_CODE (TREE_TYPE (exp)); orig_type = TREE_TYPE (exp); if (! INTEGRAL_TYPE_P (orig_type) && code != ERROR_MARK) { error ("switch quantity not an integer"); exp = integer_zero_node; } else { type = TYPE_MAIN_VARIANT (TREE_TYPE (exp)); if (warn_traditional && !in_system_header && (type == long_integer_type_node || type == long_unsigned_type_node)) warning ("`long' switch expression not converted to `int' in ISO C"); exp = default_conversion (exp); type = TREE_TYPE (exp); } } /* Add this new SWITCH_STMT to the stack. */ cs = (struct c_switch *) xmalloc (sizeof (*cs)); cs->switch_stmt = build_stmt (SWITCH_STMT, exp, NULL_TREE, orig_type); cs->cases = splay_tree_new (case_compare, NULL, NULL); cs->next = switch_stack; switch_stack = cs; return add_stmt (switch_stack->switch_stmt); } /* Process a case label. */ tree do_case (low_value, high_value) tree low_value; tree high_value; { tree label = NULL_TREE; if (switch_stack) { label = c_add_case_label (switch_stack->cases, SWITCH_COND (switch_stack->switch_stmt), low_value, high_value); if (label == error_mark_node) label = NULL_TREE; } else if (low_value) error ("case label not within a switch statement"); else error ("`default' label not within a switch statement"); return label; } /* Finish the switch statement. */ void c_finish_case () { struct c_switch *cs = switch_stack; RECHAIN_STMTS (cs->switch_stmt, SWITCH_BODY (cs->switch_stmt)); /* Pop the stack. */ switch_stack = switch_stack->next; splay_tree_delete (cs->cases); free (cs); }