https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120882
Bug ID: 120882
Summary: internal compiler error in
/opt/compiler-explorer/gcc-trunk-20250630/include/c++/
16.0.0/concepts since 11.1 only with -std=c++23, with
c++20 works fine
Product: gcc
Version: 16.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: mario.rodriguezb1 at um dot es
Target Milestone: ---
Program:
```
#include <cstdarg>
#include <string_view>
void print_all(const char *,...) {
va_list args;
va_start(args, __builtin_va_arg_pack());
std::apply([=](const std::string_view& fmt, auto... args) {
print(fmt.c_str(), std::forward<decltype(args)>(args)...);
}, std::tuple(std::string_view{args}...));
va_end(args);
```
Stack dump:
```
/opt/compiler-explorer/gcc-trunk-20250630/include/c++/16.0.0/concepts:59:15:
required for the satisfaction of '__same_as<_Tp, _Up>'in set_diagnostic_buffer,
at diagnostic.cc:1960
0x2844425 diagnostic_context::diagnostic_impl(rich_location*,
diagnostic_metadata const*, diagnostic_option_id, char const*, __va_list_tag
(*) [1], diagnostic_t)
???:0
0x2866fc6 internal_error(char const*, ...)
???:0
0xaede72 fancy_abort(char const*, int, char const*)
???:0
0x284383b diagnostic_context::finish()
???:0
0x2843b87 diagnostic_context::action_after_output(diagnostic_t)
???:0
0x284430e diagnostic_context::report_diagnostic(diagnostic_info*)
???:0
0x2844425 diagnostic_context::diagnostic_impl(rich_location*,
diagnostic_metadata const*, diagnostic_option_id, char const*, __va_list_tag
(*) [1], diagnostic_t)
???:0
0x2865821 warning(diagnostic_option_id, char const*, ...)
???:0
0xe05148 build_type_attribute_qual_variant(tree_node*, tree_node*, int)
???:0
0xdc5dd2 cp_build_type_attribute_variant(tree_node*, tree_node*)
???:0
0xd23306 canonicalize_type_argument(tree_node*, int)
???:0
0xd69e73 coerce_template_parms(tree_node*, tree_node*, tree_node*, int, bool)
???:0
0xd4a08f lookup_template_class(tree_node*, tree_node*, tree_node*, tree_node*,
int)
???:0
0xd4b562 tsubst(tree_node*, tree_node*, int, tree_node*)
???:0
0xd4be07 tsubst(tree_node*, tree_node*, int, tree_node*)
???:0
0xc0e05a maybe_print_single_constraint_context(diagnostic_text_output_format&,
tree_node*)
???:0
0x2864678 diagnostic_text_output_format::on_report_diagnostic(diagnostic_info
const&, diagnostic_t)
???:0
0x2843f76 diagnostic_context::report_diagnostic(diagnostic_info*)
???:0
0x2844425 diagnostic_context::diagnostic_impl(rich_location*,
diagnostic_metadata const*, diagnostic_option_id, char const*, __va_list_tag
(*) [1], diagnostic_t)
???:0
0x2865821 warning(diagnostic_option_id, char const*, ...)
???:0
```
To quickly reproduce:
https://godbolt.org/z/1hGM97qvc
