[pull] master from php:master #492
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This bug happens because of a nested `SHM_UNPROTECT()` sequence. In particular: ``` unprotect memory at ext/opcache/ZendAccelerator.c:2127 protect memory at ext/opcache/ZendAccelerator.c:2160 unprotect memory at ext/opcache/ZendAccelerator.c:2164 unprotect memory at ext/opcache/jit/zend_jit_trace.c:7464 ^^^ Nested protect memory at ext/opcache/jit/zend_jit_trace.c:7591 ^^^ Problem is here: it should not protect again due to the nested unprotect protect memory at ext/opcache/ZendAccelerator.c:2191 ^^^ This one should actually protect, not the previous one ``` The reason this nesting happen is because: 1. We try to include the script, this eventually calls `cache_script_in_shared_memory` 2. `zend_optimize_script` will eventually run SCCP as part of the DFA pass. 3. SCCP will try to replace constants, but can also run destructors when a partial array is destructed here: https://github.com/php/php-src/blob/4e9cde758eadf30cc4d596d6398c2c34c64197b4/Zend/Optimizer/sccp.c#L2387-L2389 In this case, this destruction invokes the GC which invokes the tracing JIT, leading to the nested unprotects. This patch disables the GC to prevent invoking user code, as user code is not supposed to run during the optimizer pipeline. Closes GH-17249. Co-authored-by: Dmitry Stogov <[email protected]>
* PHP-8.3: Fix GH-17246: GC during SCCP causes segfault
* PHP-8.4: Fix GH-17246: GC during SCCP causes segfault
* PHP-8.3: [ci skip] Make build command for program using embed portable
* PHP-8.4: [ci skip] Make build command for program using embed portable
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