Thread safety analysis: Add note for double unlock
Summary:
When getting a warning that we release a capability that isn't held it's
sometimes not clear why. So just like we do for double locking, we add a
note on the previous release operation, which marks the point since when
the capability isn't held any longer.
We can find this previous release operation by looking up the
corresponding negative capability.
Reviewers: aaron.ballman, delesley
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D81352
diff --git a/clang/lib/Sema/AnalysisBasedWarnings.cpp b/clang/lib/Sema/AnalysisBasedWarnings.cpp
index 995d776..3b73568 100644
--- a/clang/lib/Sema/AnalysisBasedWarnings.cpp
+++ b/clang/lib/Sema/AnalysisBasedWarnings.cpp
@@ -1700,6 +1700,14 @@
: getNotes();
}
+ OptionalNotes makeUnlockedHereNote(SourceLocation LocUnlocked,
+ StringRef Kind) {
+ return LocUnlocked.isValid()
+ ? getNotes(PartialDiagnosticAt(
+ LocUnlocked, S.PDiag(diag::note_unlocked_here) << Kind))
+ : getNotes();
+ }
+
public:
ThreadSafetyReporter(Sema &S, SourceLocation FL, SourceLocation FEL)
: S(S), FunLocation(FL), FunEndLocation(FEL),
@@ -1726,13 +1734,14 @@
Warnings.emplace_back(std::move(Warning), getNotes());
}
- void handleUnmatchedUnlock(StringRef Kind, Name LockName,
- SourceLocation Loc) override {
+ void handleUnmatchedUnlock(StringRef Kind, Name LockName, SourceLocation Loc,
+ SourceLocation LocPreviousUnlock) override {
if (Loc.isInvalid())
Loc = FunLocation;
PartialDiagnosticAt Warning(Loc, S.PDiag(diag::warn_unlock_but_no_lock)
<< Kind << LockName);
- Warnings.emplace_back(std::move(Warning), getNotes());
+ Warnings.emplace_back(std::move(Warning),
+ makeUnlockedHereNote(LocPreviousUnlock, Kind));
}
void handleIncorrectUnlockKind(StringRef Kind, Name LockName,