Fix is_zend_ptr() huge block comparison #16938
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We should compare the block memory, not the block metadata (See zend_mm_add_huge_block). This caused random test failure for ext/ffi/tests/gh14626.phpt when the malloc() performed by the FFI code lies close to the block metadata, and the size of the block is large enough. This was reported by php#16902 (comment)
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We should compare the block memory allocation range, not the block metadata pointer (See zend_mm_add_huge_block).
This caused random test failure for ext/ffi/tests/gh14626.phpt when the malloc() performed by the FFI code lies close to the block metadata, and the size of the block is large enough.
This random crash was reported by #16902 (comment)
It only reproduced on 32-bit in like 1/12 tries on average on my system, so a bit hard to reproduce. Did not test on 64-bit but probably even harder to reproduce.