Compatibility macro detection for the -Wimplicit-fallthrough diagnostic.
Summary:
When issuing a diagnostic message for the -Wimplicit-fallthrough diagnostics, always try to find the latest macro, defined at the point of fallthrough, which is immediately expanded to "[[clang::fallthrough]]", and use it's name instead of the actual sequence.
Known issues:
* uses PP.getSpelling() to compare macro definition with a string (anyone can suggest a convenient way to fill a token array, or maybe lex it in runtime?);
* this can be generalized and used in other similar cases, any ideas where it should reside then?
Reviewers: doug.gregor, rsmith
Reviewed By: rsmith
CC: cfe-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D50
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@164858 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Lex/MacroInfo.cpp b/lib/Lex/MacroInfo.cpp
index 7a4964f..ffe31f2 100644
--- a/lib/Lex/MacroInfo.cpp
+++ b/lib/Lex/MacroInfo.cpp
@@ -58,6 +58,18 @@
setArgumentList(MI.ArgumentList, MI.NumArguments, PPAllocator);
}
+const MacroInfo *MacroInfo::findDefinitionAtLoc(SourceLocation L,
+ SourceManager &SM) const {
+ assert(L.isValid() && "SourceLocation is invalid.");
+ for (const MacroInfo *MI = this; MI; MI = MI->PreviousDefinition) {
+ if (MI->Location.isInvalid() || // For macros defined on the command line.
+ SM.isBeforeInTranslationUnit(MI->Location, L))
+ return (MI->UndefLocation.isInvalid() ||
+ SM.isBeforeInTranslationUnit(L, MI->UndefLocation)) ? MI : NULL;
+ }
+ return NULL;
+}
+
unsigned MacroInfo::getDefinitionLengthSlow(SourceManager &SM) const {
assert(!IsDefinitionLengthCached);
IsDefinitionLengthCached = true;