================
@@ -711,6 +711,26 @@ void InitListChecker::FillInEmptyInitForField(unsigned
Init, FieldDecl *Field,
if (VerifyOnly)
return;
+ // Enter a lifetime extension context, then we can support lifetime
+ // extension of temporary created by aggregate initialization using a
+ // default member initializer (DR1815 https://wg21.link/CWG1815).
+ //
+ // In a lifetime extension context, BuildCXXDefaultInitExpr will clone
the
+ // initializer expression on each use that would lifetime extend its
+ // temporaries.
+ EnterExpressionEvaluationContext LifetimeExtensionContext(
+ SemaRef, Sema::ExpressionEvaluationContext::PotentiallyEvaluated,
+ /*LambdaContextDecl=*/nullptr,
+ Sema::ExpressionEvaluationContextRecord::EK_Other, true);
+
+ // Lifetime extension in default-member-init.
+ auto &LastRecord = SemaRef.ExprEvalContexts.back();
+
+ // Just copy previous record, make sure we haven't forget anything.
+ LastRecord =
+ SemaRef.ExprEvalContexts[SemaRef.ExprEvalContexts.size() - 2];
+ LastRecord.InLifetimeExtendingContext = true;
----------------
zygoloid wrote:
This doesn't look right -- this would lifetime-extend *all* temporaries in the
initializer. Only those that are actually bound to a reference member should be
extended here.
Perhaps instead of these changes involving `InLifetimeExtendedContext`, you
could change `BuildCXXDefaultInitExpr` to always rebuild the initializer if it
contains any temporaries (if the initializer expression is an
`ExprWithCleanups`). Then make sure the normal lifetime extension code recurses
into the default initializer and does lifetime extension when warranted.
https://github.com/llvm/llvm-project/pull/87933
_______________________________________________
cfe-commits mailing list
cfe-commits@lists.llvm.org
https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
