Delete CC_Default and use the target default CC everywhere

Summary:
Makes functions with implicit calling convention compatible with
function types with a matching explicit calling convention.  This fixes
things like calls to qsort(), which has an explicit __cdecl attribute on
the comparator in Windows headers.

Clang will now infer the calling convention from the declarator.  There
are two cases when the CC must be adjusted during redeclaration:
1. When defining a non-inline static method.
2. When redeclaring a function with an implicit or mismatched
convention.

Fixes PR13457, and allows clang to compile CommandLine.cpp for the
Microsoft C++ ABI.

Excellent test cases provided by Alexander Zinenko!

Reviewers: rsmith

Differential Revision: http://llvm-reviews.chandlerc.com/D1231

llvm-svn: 189412

1 files changed, 1 insertions, 1 deletions

diff --git a/clang/lib/CodeGen/TargetInfo.cpp b/clang/lib/CodeGen/TargetInfo.cpp
index 70fc8fed5d4..b56684ba5c8 100644
--- a/clang/lib/CodeGen/TargetInfo.cpp
+++ b/clang/lib/CodeGen/TargetInfo.cpp
@@ -1262,7 +1262,7 @@ public:
     // that when AVX types are involved: the ABI explicitly states it is
     // undefined, and it doesn't work in practice because of how the ABI
     // defines varargs anyway.
-    if (fnType->getCallConv() == CC_Default || fnType->getCallConv() == CC_C) {
+    if (fnType->getCallConv() == CC_C) {
       bool HasAVXType = false;
       for (CallArgList::const_iterator
              it = args.begin(), ie = args.end(); it != ie; ++it) {