Fix undefined behaviour in phpdbg_load_module_or_extension #10157
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If zend_register_module_ex were to return NULL, then module_entry will be set to NULL, and the if's body will load module_entry->name. Since module_entry is NULL, loading the name would cause a NULL pointer dereference. However, since a NULL pointer dereference is undefined behaviour, the compiler is free to remove the check. Fix it by using *name instead of module_entry->name.
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If
zend_register_module_exwere to return NULL, thenmodule_entrywill be set to NULL, and the if's body will loadmodule_entry->name. Since module_entry is NULL, loading the name would cause a NULL pointer dereference. However, since a NULL pointer dereference is undefined behaviour, the compiler is free to remove the check.I verified this on my system's compiler, and indeed that check is actually removed when using Clang as a compiler. I did not test GCC, but I expect the behaviour of GCC to be the same in this case.
Fix it by using *name instead of module_entry->name.
Note: I found this using a static analysis tool and manually verified the issue.
EDIT: test failure "Test function gzfile() reading a gzip relative file [C:\projects\php-src\ext\zlib\tests\gzfile_basic.phpt]" seems unrelated