Thanks for the bug report.

Changed bundled pcre to use noopt instead of noinline.

https://github.com/MariaDB/server/pull/2700/files

Also tried without success

@@ -676,7 +676,7 @@ if (ecode == NULL)

   else

     {

     int len = (int)((char *)&rdepth - (char *)eptr);

-    return (len > 0)? -len : len;

+    return [[clang::optnone]] (len > 0)? -len : len;

     }

   }

 #endif     /* NO_RECURSE */

@@ -6408,7 +6408,7 @@ result still unsigned". Hopefully the cast fixes that. */

 if (re == NULL && extra_data == NULL && subject == NULL && length == -999 &&

     start_offset == -999)

 #ifdef NO_RECURSE

-  return -((int)sizeof(heapframe));

+  return [[clang::optnone]] -((int)sizeof(heapframe));

 #else

   return match(NULL, NULL, NULL, 0, NULL, NULL, 0);

 #endif

Thanks for the bug report.

Sorry that its a pcre one to fix and might just end up being a distro carried patch.

Thanks for letting us know so at least we can fall back to a bundled fixed version.

liuzx did you have mtr troubles on tests: Failing test(s): main.execution_constants main.sp_notembedded main.sp-error ? There might be other aspects of stack length calculation that need to be fixed for clang

I did a test and no error or warning found.

1. ./mysql-test/mtr main.execution_constants
   Logging: /var/tmp/portage/dev-db/mariadb-10.4.30/work/mysql/mysql-test/mysql-test-run.pl main.execution_constants
   VS config:
   vardir: /var/tmp/portage/dev-db/mariadb-10.4.30/work/mysql_build/mysql-test/var
   Checking leftover processes...
   Removing old var directory...
   Creating var directory '/var/tmp/portage/dev-db/mariadb-10.4.30/work/mysql_build/mysql-test/var'...
   Checking supported features...
   MariaDB Version 10.4.30-MariaDB

• SSL connections supported
• binaries built with wsrep patch
  Collecting tests...
  Installing system database...

==============================================================================

TEST RESULT TIME (ms) or COMMENT
--------------------------------------------------------------------------

worker[1] Using MTR_BUILD_THREAD 300, with reserved ports 16000..16019
worker[1] mysql-test-run: WARNING: running this script as root will cause some tests to be skipped
main.execution_constants [ pass ] 197
--------------------------------------------------------------------------
The servers were restarted 0 times
Spent 0.197 of 4 seconds executing testcases

Completed: All 1 tests were successful.

thanks for confirming.

Obviously you're welcome to take my updated pcre patch to Gentoo in any form you choose.