commit c0b4928df87a856696aee603ca994739df476675
author Alexander Kornienko <alexfh@google.com> Wed Aug 29 16:56:24 2012 +0000
committer Alexander Kornienko <alexfh@google.com> Wed Aug 29 16:56:24 2012 +0000
tree 36eac4a91b4f4a5684b87e55bfa8807211d47c15
parent 771f1607588293a2bd0f3d2a7686792cdcc5efee

Fixed a problem with #pragma push_macro/pop_macro implementation.

Summary:
The problem was with the following sequence:
  #pragma push_macro("long")
  #undef long
  #pragma pop_macro("long")
in case when "long" didn't represent a macro.
Fixed crash and removed code duplication for #undef/pop_macro case. Added regression tests.

Reviewers: doug.gregor, klimek

Reviewed By: doug.gregor

CC: cfe-commits, chapuni

Differential Revision: http://llvm-reviews.chandlerc.com/D31

llvm-svn: 162845

clang/lib/Lex/PPDirectives.cpp

diff --git a/clang/lib/Lex/PPDirectives.cpp b/clang/lib/Lex/PPDirectives.cpp
index 6de0e4a..738bed3 100644
--- a/clang/lib/Lex/PPDirectives.cpp
+++ b/clang/lib/Lex/PPDirectives.cpp
@@ -1921,10 +1921,7 @@
     WarnUnusedMacroLocs.erase(MI->getDefinitionLoc());
 
   MI->setUndefLoc(MacroNameTok.getLocation());
-  IdentifierInfo *II = MacroNameTok.getIdentifierInfo();
-  II->setHasMacroDefinition(false);
-  if (II->isFromAST())
-    II->setChangedSinceDeserialization();
+  clearMacroInfo(MacroNameTok.getIdentifierInfo());
 }
 
 

clang/lib/Lex/PPMacroExpansion.cpp

diff --git a/clang/lib/Lex/PPMacroExpansion.cpp b/clang/lib/Lex/PPMacroExpansion.cpp
index 936b370..3f27236 100644
--- a/clang/lib/Lex/PPMacroExpansion.cpp
+++ b/clang/lib/Lex/PPMacroExpansion.cpp
@@ -57,6 +57,15 @@
     II->setChangedSinceDeserialization();
 }
 
+/// \brief Undefine a macro for this identifier.
+void Preprocessor::clearMacroInfo(IdentifierInfo *II) {
+  assert(II->hasMacroDefinition() && "Macro is not defined!");
+  assert(Macros[II]->getUndefLoc().isValid() && "Macro is still defined!");
+  II->setHasMacroDefinition(false);
+  if (II->isFromAST())
+    II->setChangedSinceDeserialization();
+}
+
 /// RegisterBuiltinMacro - Register the specified identifier in the identifier
 /// table and mark it as a builtin macro to be expanded.
 static IdentifierInfo *RegisterBuiltinMacro(Preprocessor &PP, const char *Name){

clang/lib/Lex/Pragma.cpp

diff --git a/clang/lib/Lex/Pragma.cpp b/clang/lib/Lex/Pragma.cpp
index acf5c74..62ef8bf 100644
--- a/clang/lib/Lex/Pragma.cpp
+++ b/clang/lib/Lex/Pragma.cpp
@@ -737,13 +737,18 @@
     if (MacroInfo *CurrentMI = getMacroInfo(IdentInfo)) {
       if (CurrentMI->isWarnIfUnused())
         WarnUnusedMacroLocs.erase(CurrentMI->getDefinitionLoc());
+      CurrentMI->setUndefLoc(MessageLoc);
     }
 
     // Get the MacroInfo we want to reinstall.
     MacroInfo *MacroToReInstall = iter->second.back();
 
-    // Reinstall the previously pushed macro.
-    setMacroInfo(IdentInfo, MacroToReInstall);
+    if (MacroToReInstall) {
+      // Reinstall the previously pushed macro.
+      setMacroInfo(IdentInfo, MacroToReInstall);
+    } else if (IdentInfo->hasMacroDefinition()) {
+      clearMacroInfo(IdentInfo);
+    }
 
     // Pop PragmaPushMacroInfo stack.
     iter->second.pop_back();