P0012R1: Make exception specifications be part of the type system. This

implements the bulk of the change (modifying the type system to include
exception specifications), but not all the details just yet.

llvm-svn: 284337

4 files changed, 17 insertions, 7 deletions

diff --git a/clang/include/clang/AST/Type.h b/clang/include/clang/AST/Type.h
index fb1b50f7aac..e9351a9e514 100644
--- a/clang/include/clang/AST/Type.h
+++ b/clang/include/clang/AST/Type.h
@@ -3364,9 +3364,15 @@ public:
     return reinterpret_cast<FunctionDecl *const *>(param_type_end())[1];
   }
   /// Determine whether this function type has a non-throwing exception
+  /// specification.
+  CanThrowResult canThrow(const ASTContext &Ctx) const;
+  /// Determine whether this function type has a non-throwing exception
   /// specification. If this depends on template arguments, returns
   /// \c ResultIfDependent.
-  bool isNothrow(const ASTContext &Ctx, bool ResultIfDependent = false) const;
+  bool isNothrow(const ASTContext &Ctx, bool ResultIfDependent = false) const {
+    return ResultIfDependent ? canThrow(Ctx) != CT_Can
+                             : canThrow(Ctx) == CT_Cannot;
+  }
 
   bool isVariadic() const { return Variadic; }
 
diff --git a/clang/include/clang/Basic/DiagnosticSemaKinds.td b/clang/include/clang/Basic/DiagnosticSemaKinds.td
index b92ca3d34b9..e274b464652 100644
--- a/clang/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/clang/include/clang/Basic/DiagnosticSemaKinds.td
@@ -1644,7 +1644,8 @@ def err_init_conversion_failed : Error<
   "%select{none|const|restrict|const and restrict|volatile|const and volatile|"
   "volatile and restrict|const, volatile, and restrict}5 vs "
   "%select{none|const|restrict|const and restrict|volatile|const and volatile|"
-  "volatile and restrict|const, volatile, and restrict}6)}4">;
+  "volatile and restrict|const, volatile, and restrict}6)"
+  "|: different exception specifications}4">;
 
 def err_lvalue_to_rvalue_ref : Error<"rvalue reference %diff{to type $ cannot "
   "bind to lvalue of type $|cannot bind to incompatible lvalue}0,1">;
@@ -3278,7 +3279,8 @@ def note_ovl_candidate : Note<"candidate "
     "%select{none|const|restrict|const and restrict|volatile|const and volatile"
     "|volatile and restrict|const, volatile, and restrict}3 but found "
     "%select{none|const|restrict|const and restrict|volatile|const and volatile"
-    "|volatile and restrict|const, volatile, and restrict}4)}2">;
+    "|volatile and restrict|const, volatile, and restrict}4)"
+    "| has different exception specification}2">;
 
 def note_ovl_candidate_inherited_constructor : Note<
     "constructor from base class %0 inherited here">;
@@ -6101,7 +6103,8 @@ def note_hidden_overloaded_virtual_declared_here : Note<
   "%select{none|const|restrict|const and restrict|volatile|const and volatile|"
   "volatile and restrict|const, volatile, and restrict}2 vs "
   "%select{none|const|restrict|const and restrict|volatile|const and volatile|"
-  "volatile and restrict|const, volatile, and restrict}3)}1">;
+  "volatile and restrict|const, volatile, and restrict}3)"
+  "|: different exception specifications}1">;
 def warn_using_directive_in_header : Warning<
   "using namespace directive in global context in header">,
   InGroup<HeaderHygiene>, DefaultIgnore;
@@ -6343,7 +6346,8 @@ def err_typecheck_convert_incompatible : Error<
   "%select{none|const|restrict|const and restrict|volatile|const and volatile|"
   "volatile and restrict|const, volatile, and restrict}5 vs "
   "%select{none|const|restrict|const and restrict|volatile|const and volatile|"
-  "volatile and restrict|const, volatile, and restrict}6)}4">;
+  "volatile and restrict|const, volatile, and restrict}6)"
+  "|: different exception specifications}4">;
 def err_typecheck_missing_return_type_incompatible : Error<
   "%diff{return type $ must match previous return type $|"
   "return type must match previous return type}0,1 when %select{block "
diff --git a/clang/include/clang/Sema/Overload.h b/clang/include/clang/Sema/Overload.h
index 1c2eb927895..b3447c58abb 100644
--- a/clang/include/clang/Sema/Overload.h
+++ b/clang/include/clang/Sema/Overload.h
@@ -62,7 +62,7 @@ namespace clang {
     ICK_Lvalue_To_Rvalue,      ///< Lvalue-to-rvalue conversion (C++ 4.1)
     ICK_Array_To_Pointer,      ///< Array-to-pointer conversion (C++ 4.2)
     ICK_Function_To_Pointer,   ///< Function-to-pointer (C++ 4.3)
-    ICK_NoReturn_Adjustment,   ///< Removal of noreturn from a type (Clang)
+    ICK_Function_Conversion,   ///< Function pointer conversion (C++17 4.13)
     ICK_Qualification,         ///< Qualification conversions (C++ 4.4)
     ICK_Integral_Promotion,    ///< Integral promotions (C++ 4.5)
     ICK_Floating_Promotion,    ///< Floating point promotions (C++ 4.6)
diff --git a/clang/include/clang/Sema/Sema.h b/clang/include/clang/Sema/Sema.h
index a50dd66791e..6e0f3797643 100644
--- a/clang/include/clang/Sema/Sema.h
+++ b/clang/include/clang/Sema/Sema.h
@@ -2373,7 +2373,7 @@ public:
                                     bool IgnoreBaseAccess);
   bool IsQualificationConversion(QualType FromType, QualType ToType,
                                  bool CStyle, bool &ObjCLifetimeConversion);
-  bool IsNoReturnConversion(QualType FromType, QualType ToType,
+  bool IsFunctionConversion(QualType FromType, QualType ToType,
                             QualType &ResultTy);
   bool DiagnoseMultipleUserDefinedConversion(Expr *From, QualType ToType);
   bool isSameOrCompatibleFunctionType(CanQualType Param, CanQualType Arg);