On Tue, May 26, 2026 at 09:38:33AM -0400, Marek Polacek wrote: > I'm not against this but I would think we may want to check error_operand_p > (h) > in process_metafunction instead?
That works too in reflect/* testing. 2026-05-26 Jakub Jelinek <[email protected]> PR c++/125412 * reflect.cc (process_metafunction): If ht is error_operand_p, set *non_constant_p and return NULL_TREE. * g++.dg/reflect/pr125412.C: New test. --- gcc/cp/reflect.cc.jj 2026-05-25 10:42:52.681817335 +0200 +++ gcc/cp/reflect.cc 2026-05-26 17:29:29.483733178 +0200 @@ -7887,6 +7887,11 @@ process_metafunction (const constexpr_ct if (*jump_target || *non_constant_p) return NULL_TREE; ht = REFLECT_EXPR_HANDLE (info); + if (error_operand_p (ht)) + { + *non_constant_p = true; + return NULL_TREE; + } if (METAFN_KIND_ARG (minfo, argno) == METAFN_KIND_ARG_TINFO && eval_is_type (ht) != boolean_true_node) return throw_exception_nontype (loc, ctx, fun, non_constant_p, --- gcc/testsuite/g++.dg/reflect/pr125412.C.jj 2026-05-25 12:02:08.456192292 +0200 +++ gcc/testsuite/g++.dg/reflect/pr125412.C 2026-05-25 12:10:38.405976096 +0200 @@ -0,0 +1,24 @@ +// PR c++/125412 +// { dg-do compile { target c++26 } } +// { dg-additional-options "-freflection" } + +#include <meta> + +void +foo () +{ +} + +auto bar (); + +template <typename T> +auto a = foo (); // { dg-error "variable or field 'a' declared void" } +template <typename T> +auto b = bar (); // { dg-error "use of 'auto bar\\\(\\\)' before deduction of 'auto'" } + +consteval { + auto c = substitute (^^a, { ^^int }); + std::meta::extract <int> (c); + auto d = substitute (^^b, { ^^int }); + std::meta::extract <int> (d); +} Jakub
