TCGETA, TCSETA, TCSETAF, TCSETAW termios ioctl no longer usable on all architectures with glibc 2.42

Bug report

Bug description:

The build of cpython is broken with glibc 2.42 on at least the alpha, hppa and sparc64 architectures, as reported for example on Gentoo: https://bugs.gentoo.org/962600, but also affecting Buildroot: https://autobuild.buildroot.net/results/e7d/e7d951b06e9338e622fe96b0fb02823b1ef5235c/build-end.log. The build failure looks like this:

./Modules/termios.c:1119:16: error: invalid application of 'sizeof' to incomplete type 'struct termio'
 1119 |     {"TCGETA", TCGETA},
      |                ^~~~~~
./Modules/termios.c:1131:16: error: invalid application of 'sizeof' to incomplete type 'struct termio'
 1131 |     {"TCSETA", TCSETA},
      |                ^~~~~~
./Modules/termios.c:1134:17: error: invalid application of 'sizeof' to incomplete type 'struct termio'
 1134 |     {"TCSETAF", TCSETAF},
      |                 ^~~~~~~
./Modules/termios.c:1137:17: error: invalid application of 'sizeof' to incomplete type 'struct termio'
 1137 |     {"TCSETAW", TCSETAW},
      |                 ^~~~~~~

The problem is that on those architectures, ioctls.h reference "struct termio", which has been removed from glibc 2.42. https://lists.gnu.org/archive/html/info-gnu/2025-07/msg00011.html.

While the issue is being fixed in the upstream Linux kernel, it will take time for those fixes to propagate, and a fix in Python would be relevant. PR coming.

CPython versions tested on:

3.13

Operating systems tested on:

Linux

Linked PRs

• gh-142380

Bắt đầu trong Modules/termios.c, xung quanh các mục TCGETA, TCSETA, TCSETAF và TCSETAW, rồi xem xét lỗi glibc 2.42 trên alpha, hppa và sparc64. Nếu có thể, hãy tái hiện bản build bị ảnh hưởng; công việc được xem là hoàn tất khi CPython build thành công trên các kiến trúc đó mà không có lỗi về struct termio chưa hoàn chỉnh.