[PATCH] Warn on malformed header guards

[Richard Smith]

  LGTM with one suggested change (and corresponding test).


================
Comment at: include/clang/Lex/MultipleIncludeOpt.h:103
@@ +102,3 @@
+  bool getImmediatelyAfterTopLevelIfndef() const {
+    return ImmediatelyAfterTopLevelIfndef;
+  }
----------------
Maybe this should be "ImmediatelyAfterTopLevelIfndef && !ReadAnyTokens"? I think we don't want this to fire on:

#ifndef FOO
some stuff here
#define BAR
#endif


http://llvm-reviews.chandlerc.com/D898