support operator keywords used in Windows SDK

to support operator keywords used in Windows SDK, alter token type when 
seen in system headers

Hello, I submitted D33505 to address this problem, but the 
proposal was rejected as too big a hammer.
This change will allow clang to parse the WindowsSDK header <query.h> 
which uses the operator name "or" as a field name. Treat cpp operator 
keywords as ordinary identifiers inside the Microsoft headers, but 
treat them as usual in the user's program.

Original Submitter: Melanie Blower (mibintc)

Differential Revision: https://reviews.llvm.org/D33782

llvm-svn: 305087

1 files changed, 16 insertions, 0 deletions

diff --git a/clang/test/Headers/ms-cppoperkey.cpp b/clang/test/Headers/ms-cppoperkey.cpp
new file mode 100644
index 00000000000..ca56ee17bcb
--- /dev/null
+++ b/clang/test/Headers/ms-cppoperkey.cpp
@@ -0,0 +1,16 @@
+// RUN: %clang_cc1 \
+// RUN:     -fms-compatibility -x c++-cpp-output \
+// RUN:     -ffreestanding -fsyntax-only -Werror \
+// RUN:     %s -verify
+// expected-no-diagnostics
+# 1 "t.cpp"
+# 1 "query.h" 1 3
+// MS header <query.h> uses operator keyword as field name.  
+// Compile without syntax errors.
+struct tagRESTRICTION
+  {
+   union _URes 
+     {
+       int or; // Note use of cpp operator token
+     } res;
+  };