Fix diagnostic pragmas.

Diagnostic pragmas are broken because we don't keep track of the diagnostic state changes and we only check the current/latest state.
Problems manifest if a diagnostic is emitted for a source line that has different diagnostic state than the current state; this can affect
a lot of places, like C++ inline methods, template instantiations, the lexer, etc.

Fix the issue by having the Diagnostic object keep track of the source location of the pragmas so that it is able to know what is the diagnostic state at any given source location.

Fixes rdar://8365684.

llvm-svn: 121873

1 files changed, 5 insertions, 9 deletions

diff --git a/clang/lib/Lex/PPLexerChange.cpp b/clang/lib/Lex/PPLexerChange.cpp
index 4a404059926..eef42b69d87 100644
--- a/clang/lib/Lex/PPLexerChange.cpp
+++ b/clang/lib/Lex/PPLexerChange.cpp
@@ -250,15 +250,11 @@ bool Preprocessor::HandleEndOfFile(Token &Result, bool isEndOfMacro) {
 
   CurPPLexer = 0;
 
-  // This is the end of the top-level file.  If the diag::pp_macro_not_used
-  // diagnostic is enabled, look for macros that have not been used.
-  if (getDiagnostics().getDiagnosticLevel(diag::pp_macro_not_used) !=
-        Diagnostic::Ignored) {
-    for (macro_iterator I = macro_begin(false), E = macro_end(false); 
-         I != E; ++I)
-      if (!I->second->isUsed())
-        Diag(I->second->getDefinitionLoc(), diag::pp_macro_not_used);
-  }
+  // This is the end of the top-level file. 'WarnUnusedMacroLocs' has collected
+  // all macro locations that we need to warn because they are not used.
+  for (WarnUnusedMacroLocsTy::iterator
+         I=WarnUnusedMacroLocs.begin(), E=WarnUnusedMacroLocs.end(); I!=E; ++I)
+    Diag(*I, diag::pp_macro_not_used);
 
   return true;
 }