Author: Adam Czachorowski Date: 2021-01-25T15:02:25+01:00 New Revision: d462aa5a619ab9fdf8b024e48c19bc8820fe8781
URL: https://github.com/llvm/llvm-project/commit/d462aa5a619ab9fdf8b024e48c19bc8820fe8781 DIFF: https://github.com/llvm/llvm-project/commit/d462aa5a619ab9fdf8b024e48c19bc8820fe8781.diff LOG: [clang] Fix a nullptr dereference bug on invalid code When working with invalid code, we would try to dereference a nullptr while deducing template arguments in some dependend code operating on a lambda with invalid return type. Differential Revision: https://reviews.llvm.org/D95145 Added: clang/test/SemaCXX/subst-func-type-invalid-ret-type.cpp Modified: clang/lib/Sema/SemaTemplateInstantiateDecl.cpp Removed: ################################################################################ diff --git a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp index d3d6df5e0064..dc1e0ef60cac 100644 --- a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp +++ b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp @@ -4189,6 +4189,9 @@ TemplateDeclInstantiator::SubstFunctionType(FunctionDecl *D, for (unsigned OldIdx = 0, NumOldParams = OldProtoLoc.getNumParams(); OldIdx != NumOldParams; ++OldIdx) { ParmVarDecl *OldParam = OldProtoLoc.getParam(OldIdx); + if (!OldParam) + return nullptr; + LocalInstantiationScope *Scope = SemaRef.CurrentInstantiationScope; Optional<unsigned> NumArgumentsInExpansion; diff --git a/clang/test/SemaCXX/subst-func-type-invalid-ret-type.cpp b/clang/test/SemaCXX/subst-func-type-invalid-ret-type.cpp new file mode 100644 index 000000000000..c78ffff3ff50 --- /dev/null +++ b/clang/test/SemaCXX/subst-func-type-invalid-ret-type.cpp @@ -0,0 +1,16 @@ +// RUN: %clang -fsyntax-only -std=c++17 %s -Xclang -verify + +// The important part is that we do not crash. + +template<typename T> T declval(); + +template <typename T> +auto Call(T x) -> decltype(declval<T>()(0)) {} // expected-note{{candidate template ignored}} + +class Status {}; + +void fun() { + // The Status() (instead of Status) here used to cause a crash. + Call([](auto x) -> Status() {}); // expected-error{{function cannot return function type 'Status ()}} + // expected-error@-1{{no matching function for call to 'Call'}} +} _______________________________________________ llvm-branch-commits mailing list llvm-branch-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-branch-commits
