Make it possible for builtins to expression FILE* arguments, so that

we can define builtins such as fprintf, vfprintf, and
__builtin___fprintf_chk. Give a nice error message when we need to
implicitly declare a function like fprintf.

llvm-svn: 64526

6 files changed, 44 insertions, 16 deletions

diff --git a/clang/lib/AST/Builtins.cpp b/clang/lib/AST/Builtins.cpp
index e7ec1372a8e..e345898b79c 100644
--- a/clang/lib/AST/Builtins.cpp
+++ b/clang/lib/AST/Builtins.cpp
@@ -87,6 +87,7 @@ Builtin::Context::isPrintfLike(unsigned ID, unsigned &FormatIdx,
 /// DecodeTypeFromStr - This decodes one type descriptor from Str, advancing the
 /// pointer over the consumed characters.  This returns the resultant type.
 static QualType DecodeTypeFromStr(const char *&Str, ASTContext &Context, 
+                                  Builtin::Context::GetBuiltinTypeError &Error,
                                   bool AllowTypeModifiers = true) {
   // Modifiers.
   bool Long = false, LongLong = false, Signed = false, Unsigned = false;
@@ -202,10 +203,23 @@ static QualType DecodeTypeFromStr(const char *&Str, ASTContext &Context,
     
     Str = End;
     
-    QualType ElementType = DecodeTypeFromStr(Str, Context, false);
+    QualType ElementType = DecodeTypeFromStr(Str, Context, Error, false);
     Type = Context.getVectorType(ElementType, NumElements);
     break;
   }
+  case 'P': {
+    IdentifierInfo *II = &Context.Idents.get("FILE");
+    DeclContext::lookup_result Lookup 
+      = Context.getTranslationUnitDecl()->lookup(II);
+    if (Lookup.first != Lookup.second && isa<TypeDecl>(*Lookup.first)) {
+      Type = Context.getTypeDeclType(cast<TypeDecl>(*Lookup.first));
+      break;
+    }
+    else {
+      Error = Builtin::Context::GE_Missing_FILE;
+      return QualType();
+    }
+  }
   }
   
   if (!AllowTypeModifiers)
@@ -231,16 +245,21 @@ static QualType DecodeTypeFromStr(const char *&Str, ASTContext &Context,
 }
 
 /// GetBuiltinType - Return the type for the specified builtin.
-QualType Builtin::Context::GetBuiltinType(unsigned id,
-                                          ASTContext &Context) const {
+QualType Builtin::Context::GetBuiltinType(unsigned id, ASTContext &Context,
+                                          GetBuiltinTypeError &Error) const {
   const char *TypeStr = GetRecord(id).Type;
   
   llvm::SmallVector<QualType, 8> ArgTypes;
   
-  QualType ResType = DecodeTypeFromStr(TypeStr, Context);
+  Error = GE_None;
+  QualType ResType = DecodeTypeFromStr(TypeStr, Context, Error);
+  if (Error != GE_None)
+    return QualType();
   while (TypeStr[0] && TypeStr[0] != '.') {
-    QualType Ty = DecodeTypeFromStr(TypeStr, Context);
-    
+    QualType Ty = DecodeTypeFromStr(TypeStr, Context, Error);
+    if (Error != GE_None)
+      return QualType();
+
     // Do array -> pointer decay.  The builtin should use the decayed type.
     if (Ty->isArrayType())
       Ty = Context.getArrayDecayedType(Ty);
diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index 03de730f655..ba77e44288c 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -852,7 +852,10 @@ llvm::Function *CodeGenModule::getBuiltinLibFunction(unsigned BuiltinID) {
     Name += 10;
   
   // Get the type for the builtin.
-  QualType Type = Context.BuiltinInfo.GetBuiltinType(BuiltinID, Context);
+  Builtin::Context::GetBuiltinTypeError Error;
+  QualType Type = Context.BuiltinInfo.GetBuiltinType(BuiltinID, Context, Error);
+  assert(Error == Builtin::Context::GE_None && "Can't get builtin type");
+
   const llvm::FunctionType *Ty = 
     cast<llvm::FunctionType>(getTypes().ConvertType(Type));
 
diff --git a/clang/lib/Sema/Sema.cpp b/clang/lib/Sema/Sema.cpp
index 45ef03506f2..4666250c4a7 100644
--- a/clang/lib/Sema/Sema.cpp
+++ b/clang/lib/Sema/Sema.cpp
@@ -133,9 +133,7 @@ Sema::Sema(Preprocessor &pp, ASTContext &ctxt, ASTConsumer &consumer)
 
   KnownFunctionIDs[id_NSLog]         = &IT.get("NSLog");
   KnownFunctionIDs[id_asprintf]      = &IT.get("asprintf");
-  KnownFunctionIDs[id_fprintf]       = &IT.get("fprintf");
   KnownFunctionIDs[id_vasprintf]     = &IT.get("vasprintf");
-  KnownFunctionIDs[id_vfprintf]      = &IT.get("vfprintf");
 
   StdNamespace = 0;
   TUScope = 0;
diff --git a/clang/lib/Sema/Sema.h b/clang/lib/Sema/Sema.h
index db0837710f6..f202ad409a1 100644
--- a/clang/lib/Sema/Sema.h
+++ b/clang/lib/Sema/Sema.h
@@ -182,9 +182,7 @@ public:
   enum {
     id_NSLog,
     id_asprintf,
-    id_fprintf,
     id_vasprintf,
-    id_vfprintf,
     id_num_known_functions
   };
   
diff --git a/clang/lib/Sema/SemaChecking.cpp b/clang/lib/Sema/SemaChecking.cpp
index ab712554965..7ecc304fc90 100644
--- a/clang/lib/Sema/SemaChecking.cpp
+++ b/clang/lib/Sema/SemaChecking.cpp
@@ -87,12 +87,10 @@ Sema::CheckFunctionCall(FunctionDecl *FDecl, CallExpr *TheCall) {
   } else if (FnInfo == KnownFunctionIDs[id_NSLog]) {
     format_idx = 0;
     HasVAListArg = false;
-  } else if (FnInfo == KnownFunctionIDs[id_asprintf] ||
-             FnInfo == KnownFunctionIDs[id_fprintf]) {
+  } else if (FnInfo == KnownFunctionIDs[id_asprintf]) {
     format_idx = 1;
     HasVAListArg = false;
-  } else if (FnInfo == KnownFunctionIDs[id_vasprintf] ||
-             FnInfo == KnownFunctionIDs[id_vfprintf]) {
+  } else if (FnInfo == KnownFunctionIDs[id_vasprintf]) {
     format_idx = 1;
     HasVAListArg = true;
   } else {
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index 3c02d4b2946..16e8691f10b 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -298,7 +298,19 @@ NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid,
   if (Context.BuiltinInfo.hasVAListUse(BID))
     InitBuiltinVaListType();
 
-  QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context);  
+  Builtin::Context::GetBuiltinTypeError Error;
+  QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context, Error);  
+  switch (Error) {
+  case Builtin::Context::GE_None:
+    // Okay
+    break;
+
+  case Builtin::Context::GE_Missing_FILE:
+    if (ForRedeclaration)
+      Diag(Loc, diag::err_implicit_decl_requires_stdio)
+        << Context.BuiltinInfo.GetName(BID);
+    return 0;
+  }
 
   if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) {
     Diag(Loc, diag::ext_implicit_lib_function_decl)