On Wed, Oct 15, 2025 at 2:17 PM Jonathan Wakely <[email protected]> wrote:
> The preprocessor condition for defining the new __to_timeout_timespec
> function templates did not match all the conditions under which it's
> needed.
>
> std::this_thread::sleep_for is defined #if ! defined _GLIBCXX_NO_SLEEP
> but it relies on __to_timeout_timespec which was only being defined for
> targets that use nanosleep, or clock_gettime, or use gthreads.
>
> For a non-gthreads target that uses POSIX sleep to implement
> std::this_thread::sleep_for, the build fails with:
>
> include/bits/this_thread_sleep.h:71:40: error: '__to_timeout_timespec' is
> not a member of 'std::chrono' [-Wtemplate-body]
> 71 | struct timespec __ts =
> chrono::__to_timeout_timespec(__rtime);
> | ^~~~~~~~~~~~~~~~~~~~~
>
> Presumably the same would happen for mingw-w64 if configured with
> --disable-threads (as that would be a non-gthreads target that doesn't
> use nanosleep or clock_gettime).
>
> libstdc++-v3/ChangeLog:
>
> * include/bits/chrono.h (__to_timeout_timespec): Fix
> preprocessor condition to match the conditions under which
> callers of this function are defined.
> * include/bits/this_thread_sleep.h: Remove unused include.
> ---
>
> Bootstrapped arm-eabi, testing on powerpc64le-linux now.
>
Do we need to even try to ifdef this function, it's template and would not
be instantiated.
Except ::timespec, there seems to be nothing that it would depend on that
wouldn't be generally available.
> libstdc++-v3/include/bits/chrono.h | 4 ++--
> libstdc++-v3/include/bits/this_thread_sleep.h | 1 -
> 2 files changed, 2 insertions(+), 3 deletions(-)
>
> diff --git a/libstdc++-v3/include/bits/chrono.h
> b/libstdc++-v3/include/bits/chrono.h
> index 7f505aa0f0ff..2b0550b15f76 100644
> --- a/libstdc++-v3/include/bits/chrono.h
> +++ b/libstdc++-v3/include/bits/chrono.h
> @@ -1515,8 +1515,8 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
> } // namespace filesystem
> #endif // C++17 && HOSTED
>
> -#if defined _GLIBCXX_USE_NANOSLEEP || defined _GLIBCXX_USE_CLOCK_REALTIME
> \
> - || defined _GLIBCXX_HAS_GTHREADS
> +#if ! defined _GLIBCXX_NO_SLEEP || defined _GLIBCXX_HAS_GTHREADS \
> + || _GLIBCXX_HAVE_LINUX_FUTEX
> namespace chrono
> {
> /// @cond undocumented
> diff --git a/libstdc++-v3/include/bits/this_thread_sleep.h
> b/libstdc++-v3/include/bits/this_thread_sleep.h
> index 01f25dda2af0..7c9d573d86d8 100644
> --- a/libstdc++-v3/include/bits/this_thread_sleep.h
> +++ b/libstdc++-v3/include/bits/this_thread_sleep.h
> @@ -36,7 +36,6 @@
>
> #if __cplusplus >= 201103L
> #include <bits/chrono.h> // std::chrono::*
> -#include <ext/numeric_traits.h> // __int_traits
>
> #ifdef _GLIBCXX_USE_NANOSLEEP
> # include <cerrno> // errno, EINTR
> --
> 2.51.0
>
>
