diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp --- a/clang/lib/Sema/SemaExpr.cpp +++ b/clang/lib/Sema/SemaExpr.cpp @@ -16585,7 +16585,8 @@ } ExprResult Sema::CheckForImmediateInvocation(ExprResult E, FunctionDecl *Decl) { - if (!E.isUsable() || !Decl || !Decl->isConsteval() || isConstantEvaluated() || + if (isUnevaluatedContext() || !E.isUsable() || !Decl || + !Decl->isConsteval() || isConstantEvaluated() || RebuildingImmediateInvocation) return E; @@ -18702,8 +18703,8 @@ OdrUse = false; if (auto *FD = dyn_cast(E->getDecl())) - if (!isConstantEvaluated() && FD->isConsteval() && - !RebuildingImmediateInvocation) + if (!isUnevaluatedContext() && !isConstantEvaluated() && + FD->isConsteval() && !RebuildingImmediateInvocation) ExprEvalContexts.back().ReferenceToConsteval.insert(E); MarkExprReferenced(*this, E->getLocation(), E->getDecl(), E, OdrUse, RefsMinusAssignments); diff --git a/clang/test/CXX/basic/basic.def.odr/p2-typeid.cpp b/clang/test/CXX/basic/basic.def.odr/p2-typeid.cpp --- a/clang/test/CXX/basic/basic.def.odr/p2-typeid.cpp +++ b/clang/test/CXX/basic/basic.def.odr/p2-typeid.cpp @@ -1,4 +1,5 @@ // RUN: %clang_cc1 -fsyntax-only -verify %s +// RUN: %clang_cc1 -std=c++20 -fsyntax-only -verify %s // C++ [basic.def.odr]p2: // An expression is potentially evaluated unless it [...] is the @@ -16,7 +17,7 @@ struct NonPoly { }; -template +template struct X { Result f(T t) { return t + t; } // expected-error{{invalid operands}} @@ -34,3 +35,33 @@ // Triggers an error (as it should); xpr.g(Poly()); // expected-note{{instantiation of member function}} } + +#if __cplusplus >= 202002L + +namespace unevaluated { + +struct S { + void f(); +}; +struct T { + virtual void f(); +}; + +consteval S *null_s() { return nullptr; } +consteval S *make_s() { return new S; } +consteval T *null_t() { return nullptr; } +consteval T *make_t() { return new T; } // #alloc + +void func() { + (void)typeid(*null_s()); + (void)typeid(*make_s()); + (void)typeid(*null_t()); // expected-warning {{expression with side effects will be evaluated despite being used as an operand to 'typeid'}} + (void)typeid(*make_t()); // expected-error {{call to consteval function 'unevaluated::make_t' is not a constant expression}} \ + expected-note {{pointer to heap-allocated object is not a constant expression}} \ + expected-note@#alloc {{heap allocation performed here}} \ + expected-warning {{expression with side effects will be evaluated despite being used as an operand to 'typeid'}} +} + +} // namespace unevaluated + +#endif diff --git a/clang/test/SemaCXX/cxx2a-consteval.cpp b/clang/test/SemaCXX/cxx2a-consteval.cpp --- a/clang/test/SemaCXX/cxx2a-consteval.cpp +++ b/clang/test/SemaCXX/cxx2a-consteval.cpp @@ -594,3 +594,21 @@ } } // namespace special_ctor + +namespace unevaluated { + +template struct is_same { static const bool value = false; }; +template struct is_same { static const bool value = true; }; + +long f(); // expected-note {{declared here}} +auto consteval g(auto a) { + return a; +} + +auto e = g(f()); // expected-error {{is not a constant expression}} + // expected-note@-1 {{non-constexpr function 'f' cannot be used in a constant expression}} + +using T = decltype(g(f())); +static_assert(is_same::value); + +} // namespace unevaluated diff --git a/clang/www/cxx_status.html b/clang/www/cxx_status.html --- a/clang/www/cxx_status.html +++ b/clang/www/cxx_status.html @@ -1103,10 +1103,11 @@ Immediate functions (consteval) P1073R3 - No + Partial P1937R2 + Clang 13 std::is_constant_evaluated