Implement support for -fwrapv, rdar://7221421

As part of this, pull together trapv handling into the same enum.

This also add support for NSW multiplies.

This also makes PCH disagreement on overflow behavior silent, since it
really doesn't matter except for warnings and codegen (no macros get 
defined etc).

llvm-svn: 106956

1 files changed, 2 insertions, 5 deletions

diff --git a/clang/lib/Frontend/PCHWriter.cpp b/clang/lib/Frontend/PCHWriter.cpp
index 3c42d474dc0..efed0f0a6c4 100644
--- a/clang/lib/Frontend/PCHWriter.cpp
+++ b/clang/lib/Frontend/PCHWriter.cpp
@@ -833,11 +833,8 @@ void PCHWriter::WriteLanguageOptions(const LangOptions &LangOpts) {
   Record.push_back(LangOpts.MathErrno); // Math functions must respect errno
                                   // (modulo the platform support).
 
-  Record.push_back(LangOpts.OverflowChecking); // Extension to call a handler function when
-                                  // signed integer arithmetic overflows.
-
-  Record.push_back(LangOpts.HeinousExtensions); // Extensions that we really don't like and
-                                  // may be ripped out at any time.
+  Record.push_back(LangOpts.getSignedOverflowBehavior());
+  Record.push_back(LangOpts.HeinousExtensions);
 
   Record.push_back(LangOpts.Optimize); // Whether __OPTIMIZE__ should be defined.
   Record.push_back(LangOpts.OptimizeSize); // Whether __OPTIMIZE_SIZE__ should be