commit 196ac334f32f81d9fe040d51de4117c86c7087bf
author David Majnemer <david.majnemer@gmail.com> Thu Sep 11 23:05:02 2014 +0000
committer David Majnemer <david.majnemer@gmail.com> Thu Sep 11 23:05:02 2014 +0000
tree 1ed72f0ee4a978653049c6ecf2be7dc0b266250d
parent 42fa4af8fe4e672d0b8bd4a5ebeec9b45730a0ff

MS ABI: Use the correct this arg when generating implict copy ctor

We assumed that the incoming this argument would be the last argument.

However, this is not true under the MS ABI.

This fixes PR20897.

llvm-svn: 217642

clang/lib/CodeGen/CGClass.cpp

diff --git a/clang/lib/CodeGen/CGClass.cpp b/clang/lib/CodeGen/CGClass.cpp
index 1de325f..72869d8 100644
--- a/clang/lib/CodeGen/CGClass.cpp
+++ b/clang/lib/CodeGen/CGClass.cpp
@@ -914,11 +914,12 @@
   private:
 
     /// Get source argument for copy constructor. Returns null if not a copy
-    /// constructor. 
-    static const VarDecl* getTrivialCopySource(const CXXConstructorDecl *CD,
+    /// constructor.
+    static const VarDecl *getTrivialCopySource(CodeGenFunction &CGF,
+                                               const CXXConstructorDecl *CD,
                                                FunctionArgList &Args) {
       if (CD->isCopyOrMoveConstructor() && CD->isDefaulted())
-        return Args[Args.size() - 1];
+        return Args[CGF.CGM.getCXXABI().getSrcArgforCopyCtor(CD, Args)];
       return nullptr;
     }
 
@@ -949,7 +950,7 @@
   public:
     ConstructorMemcpyizer(CodeGenFunction &CGF, const CXXConstructorDecl *CD,
                           FunctionArgList &Args)
-      : FieldMemcpyizer(CGF, CD->getParent(), getTrivialCopySource(CD, Args)),
+      : FieldMemcpyizer(CGF, CD->getParent(), getTrivialCopySource(CGF, CD, Args)),
         ConstructorDecl(CD),
         MemcpyableCtor(CD->isDefaulted() &&
                        CD->isCopyOrMoveConstructor() &&