diff --git a/clang/include/clang/Basic/Diagnostic.h b/clang/include/clang/Basic/Diagnostic.h --- a/clang/include/clang/Basic/Diagnostic.h +++ b/clang/include/clang/Basic/Diagnostic.h @@ -1565,7 +1565,7 @@ /// currently in-flight diagnostic. class Diagnostic { const DiagnosticsEngine *DiagObj; - StringRef StoredDiagMessage; + std::optional StoredDiagMessage; public: explicit Diagnostic(const DiagnosticsEngine *DO) : DiagObj(DO) {} diff --git a/clang/lib/Basic/Diagnostic.cpp b/clang/lib/Basic/Diagnostic.cpp --- a/clang/lib/Basic/Diagnostic.cpp +++ b/clang/lib/Basic/Diagnostic.cpp @@ -793,8 +793,8 @@ /// array. void Diagnostic:: FormatDiagnostic(SmallVectorImpl &OutStr) const { - if (!StoredDiagMessage.empty()) { - OutStr.append(StoredDiagMessage.begin(), StoredDiagMessage.end()); + if (StoredDiagMessage.has_value()) { + OutStr.append(StoredDiagMessage->begin(), StoredDiagMessage->end()); return; } diff --git a/clang/unittests/Basic/DiagnosticTest.cpp b/clang/unittests/Basic/DiagnosticTest.cpp --- a/clang/unittests/Basic/DiagnosticTest.cpp +++ b/clang/unittests/Basic/DiagnosticTest.cpp @@ -9,6 +9,7 @@ #include "clang/Basic/Diagnostic.h" #include "clang/Basic/DiagnosticError.h" #include "clang/Basic/DiagnosticIDs.h" +#include "clang/Basic/DiagnosticLex.h" #include "gtest/gtest.h" #include @@ -128,4 +129,27 @@ EXPECT_EQ(*Value, std::make_pair(20, 1)); EXPECT_EQ(Value->first, 20); } + +TEST(DiagnosticTest, storedDiagEmptyWarning) { + DiagnosticsEngine Diags(new DiagnosticIDs(), new DiagnosticOptions, + new IgnoringDiagConsumer()); + + class CaptureDiagnosticConsumer : public DiagnosticConsumer { + public: + SmallVector StoredDiags; + + void HandleDiagnostic(DiagnosticsEngine::Level level, + const Diagnostic &Info) override { + StoredDiags.push_back(StoredDiagnostic(level, Info)); + } + }; + + CaptureDiagnosticConsumer CaptureConsumer; + Diags.setClient(&CaptureConsumer, /*ShouldOwnClient=*/false); + Diags.Report(diag::pp_hash_warning) << ""; + ASSERT_TRUE(CaptureConsumer.StoredDiags.size() == 1); + + // Make sure an empty warning can round-trip with \c StoredDiagnostic. + Diags.Report(CaptureConsumer.StoredDiags.front()); +} }