Index: lib/Sema/SemaTemplateInstantiate.cpp =================================================================== --- lib/Sema/SemaTemplateInstantiate.cpp +++ lib/Sema/SemaTemplateInstantiate.cpp @@ -209,9 +209,11 @@ sema::TemplateDeductionInfo *DeductionInfo) : SemaRef(SemaRef), SavedInNonInstantiationSFINAEContext( SemaRef.InNonInstantiationSFINAEContext) { - // Don't allow further instantiation if a fatal error has occcured. Any - // diagnostics we might have raised will not be visible. - if (SemaRef.Diags.hasFatalErrorOccurred()) { + // Don't allow further instantiation if a fatal error and an uncompilable + // error have occcured. Any diagnostics we might have raised will not be + // visible. + if (SemaRef.Diags.hasFatalErrorOccurred() && + SemaRef.Diags.hasUncompilableErrorOccurred()) { Invalid = true; return; } Index: test/SemaCXX/instantiate-template-fatal-error.cpp =================================================================== --- /dev/null +++ test/SemaCXX/instantiate-template-fatal-error.cpp @@ -0,0 +1,22 @@ +// RUN: %clang_cc1 -fsyntax-only -verify -std=c++14 %s + +#pragma clang diagnostic fatal "-Wall" +#pragma clang diagnostic fatal "-Wold-style-cast" + +template bool foo0(const long long *a, T* b) { + return a == (const long long*)b; // expected-error {{use of old-style cast}} +} + +template +struct S1 { +}; + +template +struct S2 : S1 { + bool m1(const long long *a, T *b) const { return foo0(a, b); } +}; + +bool foo1(const long long *a, int *b) { + S2 s2; + return s2.m1(a, b); +}