On little endian:
map->p == php_magic_database
map->magic[i] = pointer into the map
map->p == NULL
map->magic[i] = pointer to allocated memory
On big endian (ppc64, s390x, ...):
map->p != php_magic_database and map->p != NULL
map->magic[i] = pointer into a copy of the map
Trying to efree pointer in the later cause memory corruption
Thanks to dkatulek / Red Hat for the report.
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