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, 12 insertions, 5 deletions

diff --git a/clang/lib/CodeGen/CGBuiltin.cpp b/clang/lib/CodeGen/CGBuiltin.cpp
index c6d270567a1..7bb4c474ee1 100644
--- a/clang/lib/CodeGen/CGBuiltin.cpp
+++ b/clang/lib/CodeGen/CGBuiltin.cpp
@@ -1068,30 +1068,37 @@ llvm::Function *CodeGenFunction::generateBuiltinOSLogHelperFunction(
   if (llvm::Function *F = CGM.getModule().getFunction(Name))
     return F;
 
+  llvm::SmallVector<QualType, 4> ArgTys;
   llvm::SmallVector<ImplicitParamDecl, 4> Params;
   Params.emplace_back(Ctx, nullptr, SourceLocation(), &Ctx.Idents.get("buffer"),
                       Ctx.VoidPtrTy, ImplicitParamDecl::Other);
+  ArgTys.emplace_back(Ctx.VoidPtrTy);
 
   for (unsigned int I = 0, E = Layout.Items.size(); I < E; ++I) {
     char Size = Layout.Items[I].getSizeByte();
     if (!Size)
       continue;
 
+    QualType ArgTy = getOSLogArgType(Ctx, Size);
     Params.emplace_back(
         Ctx, nullptr, SourceLocation(),
-        &Ctx.Idents.get(std::string("arg") + llvm::to_string(I)),
-        getOSLogArgType(Ctx, Size), ImplicitParamDecl::Other);
+        &Ctx.Idents.get(std::string("arg") + llvm::to_string(I)), ArgTy,
+        ImplicitParamDecl::Other);
+    ArgTys.emplace_back(ArgTy);
   }
 
   FunctionArgList Args;
   for (auto &P : Params)
     Args.push_back(&P);
 
+  QualType ReturnTy = Ctx.VoidTy;
+  QualType FuncionTy = Ctx.getFunctionType(ReturnTy, ArgTys, {});
+
   // The helper function has linkonce_odr linkage to enable the linker to merge
   // identical functions. To ensure the merging always happens, 'noinline' is
   // attached to the function when compiling with -Oz.
   const CGFunctionInfo &FI =
-      CGM.getTypes().arrangeBuiltinFunctionDeclaration(Ctx.VoidTy, Args);
+      CGM.getTypes().arrangeBuiltinFunctionDeclaration(ReturnTy, Args);
   llvm::FunctionType *FuncTy = CGM.getTypes().GetFunctionType(FI);
   llvm::Function *Fn = llvm::Function::Create(
       FuncTy, llvm::GlobalValue::LinkOnceODRLinkage, Name, &CGM.getModule());
@@ -1107,9 +1114,9 @@ llvm::Function *CodeGenFunction::generateBuiltinOSLogHelperFunction(
   IdentifierInfo *II = &Ctx.Idents.get(Name);
   FunctionDecl *FD = FunctionDecl::Create(
       Ctx, Ctx.getTranslationUnitDecl(), SourceLocation(), SourceLocation(), II,
-      Ctx.VoidTy, nullptr, SC_PrivateExtern, false, false);
+      FuncionTy, nullptr, SC_PrivateExtern, false, false);
 
-  StartFunction(FD, Ctx.VoidTy, Fn, FI, Args);
+  StartFunction(FD, ReturnTy, Fn, FI, Args);
 
   // Create a scope with an artificial location for the body of this function.
   auto AL = ApplyDebugLocation::CreateArtificial(*this);