Add basic support for -pthread.
 - Patch by David Chisnall, with PCH and Darwin support mixed in.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@80883 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Frontend/PCHReader.cpp b/lib/Frontend/PCHReader.cpp
index cb008c0..55dbd97 100644
--- a/lib/Frontend/PCHReader.cpp
+++ b/lib/Frontend/PCHReader.cpp
@@ -78,6 +78,7 @@
   PARSE_LANGOPT_IMPORTANT(NoBuiltin, diag::warn_pch_builtins);
   PARSE_LANGOPT_IMPORTANT(ThreadsafeStatics, 
                           diag::warn_pch_thread_safe_statics);
+  PARSE_LANGOPT_IMPORTANT(POSIXThreads, diag::warn_pch_posix_threads);
   PARSE_LANGOPT_IMPORTANT(Blocks, diag::warn_pch_blocks);
   PARSE_LANGOPT_BENIGN(EmitAllDecls);
   PARSE_LANGOPT_IMPORTANT(MathErrno, diag::warn_pch_math_errno);