Fix preloaded constant propagated to file-cached script#21281
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iluuu1994 wants to merge 3 commits intophp:PHP-8.4from
Closed
Fix preloaded constant propagated to file-cached script#21281iluuu1994 wants to merge 3 commits intophp:PHP-8.4from
iluuu1994 wants to merge 3 commits intophp:PHP-8.4from
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Since phpGH-15021 preloaded constants are propagated to compiled scripts. This is problematic for file cache, which assumes all referenced zvals are either persistently allocated or local to the current script. However, preloaded constants live in shm as immutable, but not persistent. To solve this, we'd need to duplicate propagated constants in the optimizer when file cache is used. This is error prone given it needs to happen in many places. It's debatable whether constant propagation is even correct in this case, as running the preloaded script on a restart isn't guaranteed to produce the same result. Hence, avoid the issue for now by just not relying on preloaded symbols when file cache is used. Fixes phpGH-21052
dstogov
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Feb 24, 2026
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| if (CG(compiler_options) & ZEND_COMPILE_WITH_FILE_CACHE) { | ||
| return true; | ||
| } |
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What is the reason for this change?
It's not covered by test(s) and it's not related to constants propagation.
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I'm using the term constant propagation in the loose sense. It's function inlining in this case that causes the issue. I expanded the test to cover this case as well.
dstogov
approved these changes
Feb 24, 2026
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Since GH-15021 preloaded constants are propagated to compiled scripts. This is problematic for file cache, which assumes all referenced zvals are either persistently allocated or local to the current script. However, preloaded constants live in shm as immutable, but not persistent.
To solve this, we'd need to duplicate propagated constants in the optimizer when file cache is used. This is error prone given it needs to happen in many places. It's debatable whether constant propagation is even correct in this case, as running the preloaded script on a restart isn't guaranteed to produce the same result.
Hence, avoid the issue for now by just not relying on preloaded symbols when file cache is used.
Fixes GH-21052