Warn on misuse of DiagnosticInfo classes that hold Twines (#137397)

This annotates the `Twine` passed to the constructors of the various
DiagnosticInfo subclasses with `[[clang::lifetimebound]]`, which causes
us to warn when we would try to print the twine after it had already
been destructed.

We also update `DiagnosticInfoUnsupported` to hold a `const Twine &`
like all of the other DiagnosticInfo classes, since this warning allows
us to clean up all of the places where it was being used incorrectly.

1 files changed, 1 insertions, 1 deletions

diff --git a/llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp b/llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
index e1bdc7e..b8c632d1 100644
--- a/llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
+++ b/llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
@@ -709,7 +709,7 @@ class LoweringDiagnosticInfo : public DiagnosticInfo {
   const Twine &Msg;
 
 public:
-  LoweringDiagnosticInfo(const Twine &DiagMsg,
+  LoweringDiagnosticInfo(const Twine &DiagMsg LLVM_LIFETIME_BOUND,
                          DiagnosticSeverity Severity = DS_Error)
       : DiagnosticInfo(DK_Lowering, Severity), Msg(DiagMsg) {}
   void print(DiagnosticPrinter &DP) const override { DP << Msg; }