Pass the function type instead of the return type to FunctionDecl::Create

Fix places where the return type of a FunctionDecl was being used in
place of the function type

FunctionDecl::Create() takes as its T parameter the type of function
that should be created, not the return type. Passing in the return type
looks to have been copypasta'd around a bit, but the number of correct
usages outweighs the incorrect ones so I've opted for keeping what T is
the same and fixing up the call sites instead.

This fixes a crash in Clang when attempting to compile the following
snippet of code with -fblocks -fsanitize=function -x objective-c++ (my
original repro case):

  void g(void(^)());
  void f()
  {
      __block int a = 0;
        g(^(){ a++; });
  }

as well as the following which only requires -fsanitize=function -x c++:

  void f(char * buf)
  {
      __builtin_os_log_format(buf, "");
  }

Patch by: Ben (bobsayshilol)

Differential revision: https://reviews.llvm.org/D53263

llvm-svn: 346601

1 files changed, 6 insertions, 7 deletions

diff --git a/clang/lib/Frontend/Rewrite/RewriteModernObjC.cpp b/clang/lib/Frontend/Rewrite/RewriteModernObjC.cpp
index 8b27a417369..8c2d4994bf6 100644
--- a/clang/lib/Frontend/Rewrite/RewriteModernObjC.cpp
+++ b/clang/lib/Frontend/Rewrite/RewriteModernObjC.cpp
@@ -3099,10 +3099,9 @@ Expr *RewriteModernObjC::SynthMsgSendStretCallExpr(FunctionDecl *MsgSendStretFla
                                                  SmallVectorImpl<Expr*> &MsgExprs,
                                                  ObjCMethodDecl *Method) {
   // Now do the "normal" pointer to function cast.
-  QualType castType = getSimpleFunctionType(returnType, ArgTypes,
-                                            Method ? Method->isVariadic()
-                                                   : false);
-  castType = Context->getPointerType(castType);
+  QualType FuncType = getSimpleFunctionType(
+      returnType, ArgTypes, Method ? Method->isVariadic() : false);
+  QualType castType = Context->getPointerType(FuncType);
 
   // build type for containing the objc_msgSend_stret object.
   static unsigned stretCount=0;
@@ -3176,9 +3175,9 @@ Expr *RewriteModernObjC::SynthMsgSendStretCallExpr(FunctionDecl *MsgSendStretFla
 
   // AST for __Stretn(receiver, args).s;
   IdentifierInfo *ID = &Context->Idents.get(name);
-  FunctionDecl *FD = FunctionDecl::Create(*Context, TUDecl, SourceLocation(),
-                                          SourceLocation(), ID, castType,
-                                          nullptr, SC_Extern, false, false);
+  FunctionDecl *FD =
+      FunctionDecl::Create(*Context, TUDecl, SourceLocation(), SourceLocation(),
+                           ID, FuncType, nullptr, SC_Extern, false, false);
   DeclRefExpr *DRE = new (Context) DeclRefExpr(FD, false, castType, VK_RValue,
                                                SourceLocation());
   CallExpr *STCE = new (Context) CallExpr(*Context, DRE, MsgExprs,