Author: Matheus Izvekov Date: 2021-09-07T10:45:35-07:00 New Revision: c30b2813a1d522eb9adeec2d73b1e79a8020c998
URL: https://github.com/llvm/llvm-project/commit/c30b2813a1d522eb9adeec2d73b1e79a8020c998 DIFF: https://github.com/llvm/llvm-project/commit/c30b2813a1d522eb9adeec2d73b1e79a8020c998.diff LOG: [clang] fix error recovery ICE on copy elision when returing invalid variable See PR51708. Attempting copy elision in dependent contexts with invalid variable, such as a variable with incomplete type, would cause a crash when attempting to calculate it's alignment. The fix is to just skip this optimization on invalid VarDecl, as otherwise this provides no benefit to error recovery: This functionality does not try to diagnose anything, it only calculates a flag which will affect where the variable will be allocated during codegen. Signed-off-by: Matheus Izvekov <mizve...@gmail.com> Reviewed By: rtrieu Differential Revision: https://reviews.llvm.org/D109191 (cherry picked from commit d98c34f4d7950f531661ba3f498222ccf6239a0f) Added: Modified: clang/lib/Sema/SemaTemplateInstantiateDecl.cpp clang/test/CXX/class/class.init/class.copy.elision/p3.cpp Removed: ################################################################################ diff --git a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp index be4c519307898..25f1348687581 100644 --- a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp +++ b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp @@ -1087,7 +1087,7 @@ Decl *TemplateDeclInstantiator::VisitVarDecl(VarDecl *D, SemaRef.BuildVariableInstantiation(Var, D, TemplateArgs, LateAttrs, Owner, StartingScope, InstantiatingVarTemplate); - if (D->isNRVOVariable()) { + if (D->isNRVOVariable() && !Var->isInvalidDecl()) { QualType RT; if (auto *F = dyn_cast<FunctionDecl>(DC)) RT = F->getReturnType(); diff --git a/clang/test/CXX/class/class.init/class.copy.elision/p3.cpp b/clang/test/CXX/class/class.init/class.copy.elision/p3.cpp index cd981264c9b69..7055acad6ccf9 100644 --- a/clang/test/CXX/class/class.init/class.copy.elision/p3.cpp +++ b/clang/test/CXX/class/class.init/class.copy.elision/p3.cpp @@ -518,3 +518,37 @@ template <class T> X<T> test_dependent_invalid_decl() { template X<int> test_dependent_invalid_decl<int>(); // expected-note {{requested here}} } // namespace test_auto_variables + +namespace PR51708 { + +class a1; // expected-note 4 {{forward declaration of 'PR51708::a1'}} +template <class> class A2; // expected-note 4 {{template is declared here}} +using a2 = A2<int>; + +template <class b> b f() { + // expected-error@-1 {{incomplete result type 'PR51708::a1' in function definition}} + // expected-error@-2 {{implicit instantiation of undefined template 'PR51708::A2<int>}} + + b d; + // expected-error@-1 {{variable has incomplete type 'PR51708::a1'}} + // expected-error@-2 {{implicit instantiation of undefined template 'PR51708::A2<int>}} + + return d; +} +template a1 f<a1>(); // expected-note-re {{in instantiation {{.*}} requested here}} +template a2 f<a2>(); // expected-note-re {{in instantiation {{.*}} requested here}} + +template <class b> b g() { + // expected-error@-1 {{incomplete result type 'PR51708::a1' in function definition}} + // expected-error@-2 {{implicit instantiation of undefined template 'PR51708::A2<int>}} + + b d __attribute__((aligned(1))); + // expected-error@-1 {{variable has incomplete type 'PR51708::a1'}} + // expected-error@-2 {{implicit instantiation of undefined template 'PR51708::A2<int>}} + + return d; +} +template a1 g<a1>(); // expected-note-re {{in instantiation {{.*}} requested here}} +template a2 g<a2>(); // expected-note-re {{in instantiation {{.*}} requested here}} + +} // namespace PR51708 _______________________________________________ llvm-branch-commits mailing list llvm-branch-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-branch-commits