From 86792438dc07ea1521ad254261536ecabffceb8a Mon Sep 17 00:00:00 2001
From: Rafael Espindola <rafael.espindola@gmail.com>
Date: Fri, 21 Sep 2012 20:39:32 +0000
Subject: [PATCH] Call CGM.SetLLVMFunctionAttributesForDefinition on thunks so
 that they get attributes like uwtable. Without uwtable a stack unwinder would
 be unable to go past the thunks.

llvm-svn: 164411
---
 clang/lib/CodeGen/CGVTables.cpp  |  2 ++
 clang/test/CodeGenCXX/thunks.cpp | 19 +++++++++++++++++--
 2 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/clang/lib/CodeGen/CGVTables.cpp b/clang/lib/CodeGen/CGVTables.cpp
index 76d2e9bc4bdb..774def26e9c7 100644
--- a/clang/lib/CodeGen/CGVTables.cpp
+++ b/clang/lib/CodeGen/CGVTables.cpp
@@ -466,6 +466,8 @@ void CodeGenVTables::EmitThunk(GlobalDecl GD, const ThunkInfo &Thunk,
     return;
   }
 
+  CGM.SetLLVMFunctionAttributesForDefinition(GD.getDecl(), ThunkFn);
+
   if (ThunkFn->isVarArg()) {
     // Varargs thunks are special; we can't just generate a call because
     // we can't copy the varargs.  Our implementation is rather
diff --git a/clang/test/CodeGenCXX/thunks.cpp b/clang/test/CodeGenCXX/thunks.cpp
index bf3b03e4e424..0659259c1799 100644
--- a/clang/test/CodeGenCXX/thunks.cpp
+++ b/clang/test/CodeGenCXX/thunks.cpp
@@ -1,5 +1,5 @@
-// RUN: %clang_cc1 %s -triple=x86_64-pc-linux-gnu -emit-llvm -o - | FileCheck %s
-// RUN: %clang_cc1 %s -triple=x86_64-pc-linux-gnu -fhidden-weak-vtables -emit-llvm -o - | FileCheck -check-prefix=HIDDEN %s
+// RUN: %clang_cc1 %s -triple=x86_64-pc-linux-gnu -munwind-tables -emit-llvm -o - | FileCheck %s
+// RUN: %clang_cc1 %s -triple=x86_64-pc-linux-gnu -munwind-tables -fhidden-weak-vtables -emit-llvm -o - | FileCheck -check-prefix=HIDDEN %s
 
 namespace Test1 {
 
@@ -327,6 +327,21 @@ namespace Test13 {
   // CHECK: ret %"struct.Test13::D"*
 }
 
+namespace Test14 {
+  class A {
+    virtual void f();
+  };
+  class B {
+    virtual void f();
+  };
+  class C : public A, public B  {
+    virtual void f();
+  };
+  void C::f() {
+  }
+  // CHECK: define void @_ZThn8_N6Test141C1fEv({{.*}}) {{.*}} uwtable
+}
+
 /**** The following has to go at the end of the file ****/
 
 // This is from Test5: