Fix GH-15905: Assertion failure for TRACK_VARS_SERVER #15930
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When the superglobals are eagerly initialized, but "S" is not contained in `variables_order`, `TRACK_VARS_SERVER` is created as empty array with refcount > 1. Since this hash table may later be modified, a flag is set which allows such COW violations for assertions. However, when `register_argc_argv` is on, the so far uninitialized hash table is updated with `argv`, what causes the hash table to be initialized, what drops the allow-COW-violations flag. The following update with `argc` then triggers a refcount violation assertion. Since we consider `HT_ALLOW_COW_VIOLATION` a hack, we do not want to keep the flag during hash table initialization, so we initialize the hash table right away after creation for this code path.
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When the superglobals are eagerly initialized, but "S" is not contained in `variables_order`, `TRACK_VARS_SERVER` is created as empty array with refcount > 1. Since this hash table may later be modified, a flag is set which allows such COW violations for assertions. However, when `register_argc_argv` is on, the so far uninitialized hash table is updated with `argv`, what causes the hash table to be initialized, what drops the allow-COW-violations flag. The following update with `argc` then triggers a refcount violation assertion. Since we consider `HT_ALLOW_COW_VIOLATION` a hack, we do not want to keep the flag during hash table initialization, so we initialize the hash table right away after creation for this code path. Closes phpGH-15930.
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When the superglobals are eagerly initialized, but "S" is not contained in
variables_order,TRACK_VARS_SERVERis created as empty array with refcount > 1. Since this hash table may later be modified, a flag is set which allows such COW violations for assertions. However, whenregister_argc_argvis on, the so far uninitialized hash table is updated withargv, what causes the hash table to be initialized, what drops the allow-COW-violations flag. The following update withargcthen triggers a refcount violation assertion.Since we consider
HT_ALLOW_COW_VIOLATIONa hack, we do not want to keep the flag during hash table initialization, so we initialize the hash table right away after creation for this code path.