[Bug libstdc++/127219] <format>: make __valid_types_for_check_dynamic_spec static so check_dynamic_spec<Ts...> works with clang and EDG

[stevensudit at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=127219

Steve Sudit <stevensudit at gmail dot com> changed:

           What    |Removed                     |Added
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           Keywords|                            |patch

--- Comment #5 from Steve Sudit <stevensudit at gmail dot com> ---
Patch posted for review:
https://gcc.gnu.org/pipermail/libstdc++/2026-September/067717.html
(also on gcc-patches:
https://gcc.gnu.org/pipermail/gcc-patches/2026-September/730491.html)

Tested x86_64-pc-linux-gnu against trunk r17-3939 with the std/format
subset of the libstdc++ testsuite at -std=gnu++20, 23 and 26; no
failures. clang 23.1 accepts the attached test against the patched header