Disable _Pragma during HTML macro rewriting to keep from crashing.

The preprocessor's handling of diagnostic push/pops is stateful, so
encountering pragmas during a re-parse causes problems. HTMLRewrite
already filters out normal # directives including #pragma, so it's
clear it's not expected to be interpreting pragmas in this mode.

This fix adds a flag to Preprocessor to explicitly disable pragmas.
The "right" fix might be to separate pragma lexing from pragma
parsing so that we can throw away pragmas like we do preprocessor
directives, but right now it's important to get the fix in.

Note that this has nothing to do with the "hack" of re-using the
input preprocessor in HTMLRewrite. Even if we someday copy the
preprocessor instead of re-using it, the copy would (and should) include
the diagnostic level tables and have the same problems.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@158214 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 6 insertions, 0 deletions

diff --git a/include/clang/Lex/Preprocessor.h b/include/clang/Lex/Preprocessor.h
index 6589f84c93..0dd9477e92 100644
--- a/include/clang/Lex/Preprocessor.h
+++ b/include/clang/Lex/Preprocessor.h
@@ -131,6 +131,9 @@ class Preprocessor : public RefCountedBase<Preprocessor> {
   /// \brief Whether we have already loaded macros from the external source.
   mutable bool ReadMacrosFromExternalSource : 1;
 
+  /// \brief True if pragmas are enabled.
+  bool PragmasEnabled : 1;
+
   /// \brief True if we are pre-expanding macro arguments.
   bool InMacroArgPreExpansion;
 
@@ -416,6 +419,9 @@ public:
 
   bool getCommentRetentionState() const { return KeepComments; }
 
+  void setPragmasEnabled(bool Enabled) { PragmasEnabled = Enabled; }
+  bool getPragmasEnabled() const { return PragmasEnabled; }
+
   void SetSuppressIncludeNotFoundError(bool Suppress) {
     SuppressIncludeNotFoundError = Suppress;
   }