Fix GH-20767: build failure with preserve_none attribute enabled on mac.

[devnexen]

Established that build < 1700.4.4.1 tends to fail thus we disable the preserve_none attribute feature for these cases.

[dktapps]

This doesn't fix the issue for me. I also don't see any sign of the Apple clang build train message in my config.log.

Output of clang --version if it's helpful:

% clang --version
Apple clang version 17.0.0 (clang-1700.0.13.5)
Target: arm64-apple-darwin24.6.0
Thread model: posix
InstalledDir: /Library/Developer/CommandLineTools/usr/bin

[dktapps]

Removing the -n from the sed command allowed it to check the version, but the check still passes. Looks like AS_VERSION_COMPARE doesn't understand it.

It might be better to use this, which is defined by clang:

#define __apple_build_version__ 17000013

The working version should be 17000404 I believe.

[devnexen]

let me know if this is working out for you this time. Cheers.

[dktapps]

Yep, that did the trick

[arnaud-lb]

@devnexen do you think it would work if we added the __apple_build_version__ check here instead of what I suggested earlier?

It would be simpler, and would more directly be related to musttail.

[petk]

Would this work instead of parsing the build version from a command in shell?

diff --git a/Zend/Zend.m4 b/Zend/Zend.m4
index 33009e9909f..b89f1f26d74 100644
--- a/Zend/Zend.m4
+++ b/Zend/Zend.m4
@@ -476,6 +476,13 @@ AC_DEFUN([ZEND_CHECK_PRESERVE_NONE], [dnl
   AC_CACHE_CHECK([for preserve_none calling convention],
    [php_cv_preserve_none],
    [AC_RUN_IFELSE([AC_LANG_SOURCE([[
+
+#ifdef __apple_build_version__
+# if __apple_build_version__ < 17000404
+#  error This version of Apple Clang doesn't support preserve_none
+# endif
+#endif
+
 #include <stdio.h>
 #include <stdint.h>

[devnexen]

nice suggestion, going to try it.

[arnaud-lb]

I’m not able to test right now, but the zend_portability.h change looks right to me, and is probably enough. It also makes sense that it’s disabling musttail rather than preserve_none, even if the end result is the same, as the build issue is related to musttail.

[arnaud-lb]

Nit: please indent the nested cpp directives (with a space after the #)

[devnexen]

I do not get your suggestion @henderkes, it is not within a nested part is it ?

[henderkes]

Oops, didn't see the #endif just above. Ignore the suggestion then.

[arnaud-lb]

Thank you @devnexen!

[dktapps]

Thanks. Confirmed working on both broken clang (1700.0.13.5) and working (1700.6.3.2) with expected VM types.