__builtin_cpu_init configure check relies on void return value

[Freaky]

Description

Testing enabling ifunc support on FreeBSD, alongside having to remove the hardcoded check that disables it I also run into:

  checking for __builtin_cpu_init... no

php-src/build/php.m4

Line 2735 in f6fae19

return __builtin_cpu_init()? 1 : 0;

  AC_LINK_IFELSE([AC_LANG_PROGRAM([], [[
    return __builtin_cpu_init()? 1 : 0;
  ]])], [

While this does technically appear to return int on gcc, it's documented as void __builtin_cpu_init (void), and indeed returns such on clang. Changing this to:

  AC_LINK_IFELSE([AC_LANG_PROGRAM([], [[
    __builtin_cpu_init(); return 1;
  ]])], [

Results in a successful check and much faster addslashes, base64_encode, etc.

PHP Version

PHP 8.1.23

Operating System

FreeBSD 13.2-RELEASE

[devnexen]

Would you mind creating a PR ?

[Freaky]

Created as #12274. Looks like the return is superfluous.

[devnexen]

Seeing what you've done in the bugzilla ticket, do you think it would be possible to make a more targeted version ? meaning still disabling ifunc for freebsd but release < 12 ? I think it would be good to have it here instead but just few months ago we had an user using freebsd 9.2.

[Freaky]

I just created #12288.