From: Rafael Espindola <rafael.espindola@gmail.com>
Date: Mon, 13 Jul 2015 06:07:58 +0000 (+0000)
Subject: Set the linkage before setting the visibility.
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=83475c76f1e311fabf708dd17734917108dddaf0;p=clang

Set the linkage before setting the visibility.

Otherwise the visibility setting code would not know that a given
function was available_externally.

Fixes PR24097.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@242012 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/CodeGen/CGVTables.cpp b/lib/CodeGen/CGVTables.cpp
index 6493062894..e36051c205 100644
--- a/lib/CodeGen/CGVTables.cpp
+++ b/lib/CodeGen/CGVTables.cpp
@@ -364,7 +364,7 @@ void CodeGenFunction::EmitMustTailThunk(const CXXMethodDecl *MD,
   FinishFunction();
 }
 
-void CodeGenFunction::GenerateThunk(llvm::Function *Fn,
+void CodeGenFunction::generateThunk(llvm::Function *Fn,
                                     const CGFunctionInfo &FnInfo,
                                     GlobalDecl GD, const ThunkInfo &Thunk) {
   StartThunk(Fn, GD, FnInfo);
@@ -376,13 +376,6 @@ void CodeGenFunction::GenerateThunk(llvm::Function *Fn,
 
   // Make the call and return the result.
   EmitCallAndReturnForThunk(Callee, &Thunk);
-
-  // Set the right linkage.
-  CGM.setFunctionLinkage(GD, Fn);
-
-  // Set the right visibility.
-  const CXXMethodDecl *MD = cast<CXXMethodDecl>(GD.getDecl());
-  setThunkVisibility(CGM, MD, Thunk, Fn);
 }
 
 void CodeGenVTables::emitThunk(GlobalDecl GD, const ThunkInfo &Thunk,
@@ -455,11 +448,17 @@ void CodeGenVTables::emitThunk(GlobalDecl GD, const ThunkInfo &Thunk,
         CodeGenFunction(CGM).GenerateVarArgsThunk(ThunkFn, FnInfo, GD, Thunk);
   } else {
     // Normal thunk body generation.
-    CodeGenFunction(CGM).GenerateThunk(ThunkFn, FnInfo, GD, Thunk);
+    CodeGenFunction(CGM).generateThunk(ThunkFn, FnInfo, GD, Thunk);
   }
 
+  CGM.setFunctionLinkage(GD, ThunkFn);
   CGM.getCXXABI().setThunkLinkage(ThunkFn, ForVTable, GD,
                                   !Thunk.Return.isEmpty());
+
+  // Set the right visibility.
+  const CXXMethodDecl *MD = cast<CXXMethodDecl>(GD.getDecl());
+  setThunkVisibility(CGM, MD, Thunk, ThunkFn);
+
   if (CGM.supportsCOMDAT() && ThunkFn->isWeakForLinker())
     ThunkFn->setComdat(CGM.getModule().getOrInsertComdat(ThunkFn->getName()));
 }
diff --git a/lib/CodeGen/CodeGenFunction.h b/lib/CodeGen/CodeGenFunction.h
index 58bec1c248..f2bc402f8b 100644
--- a/lib/CodeGen/CodeGenFunction.h
+++ b/lib/CodeGen/CodeGenFunction.h
@@ -1294,8 +1294,8 @@ public:
   void EmitMustTailThunk(const CXXMethodDecl *MD, llvm::Value *AdjustedThisPtr,
                          llvm::Value *Callee);
 
-  /// GenerateThunk - Generate a thunk for the given method.
-  void GenerateThunk(llvm::Function *Fn, const CGFunctionInfo &FnInfo,
+  /// Generate a thunk for the given method.
+  void generateThunk(llvm::Function *Fn, const CGFunctionInfo &FnInfo,
                      GlobalDecl GD, const ThunkInfo &Thunk);
 
   llvm::Function *GenerateVarArgsThunk(llvm::Function *Fn,
diff --git a/test/CodeGenCXX/pr24097.cpp b/test/CodeGenCXX/pr24097.cpp
new file mode 100644
index 0000000000..122bf88506
--- /dev/null
+++ b/test/CodeGenCXX/pr24097.cpp
@@ -0,0 +1,20 @@
+// RUN: %clang_cc1 %s -triple=x86_64-pc-linux -fvisibility hidden -emit-llvm -O1 -disable-llvm-optzns -o - | FileCheck %s
+
+struct Filter {
+  virtual void Foo();
+};
+struct Sender {
+  virtual bool Send();
+};
+struct SyncMessageFilter : public Filter, public Sender {
+  bool Send();
+};
+struct TestSyncMessageFilter : public SyncMessageFilter {
+};
+void bar() {
+  TestSyncMessageFilter f;
+  f.Send();
+}
+
+// Test that it is not hidden
+// CHECK: define available_externally zeroext i1 @_ZThn8_N17SyncMessageFilter4SendEv