[php-src] Issue #9566: Fibers appear to be broken on FreeBSD i386

Issue: https://github.com/php/php-src/issues/9566 Author: arnaud-lb ### Description Not sure that this is a supported platform, but fibers appear to be broken on FreeBSD i386. The following code: ```php <?php $fiber = new Fiber(function() { }); $fiber->start(); ``` Resulted in this output: ``` Segmentation fault (core dumped) ``` But I expected this output instead: ``` ``` gdb: ``` gdb --args sapi/cli/php test.php (gdb) r Starting program: sapi/cli/php test.php Program received signal SIGSEGV, Segmentation fault. Address not mapped to object. jump_fcontext () at Zend/asm/jump_i386_sysv_elf_gas.S:60 60 movl %ecx, (%eax) (gdb) list 55 movl %eax, %esp 56 57 /* address of returned transport_t */ 58 movl 0x1c(%esp), %eax 59 /* return parent fcontext_t */ 60 movl %ecx, (%eax) 61 /* return data */ 62 movl %edx, 0x4(%eax) 63 64 movl 0x18(%esp), %ecx /* restore EIP */ (gdb) bt #0 jump_fcontext () at Zend/asm/jump_i386_sysv_elf_gas.S:60 #1 0x21059000 in ?? () Backtrace stopped: previous frame inner to this frame (corrupt stack?) ``` ### PHP Version master 17b0e498e5d6e4c82067cc8441f9aa72a350c2ca ### Operating System FreeBSD 13.0 i386