Assertion violation in ZendAccelerator.c

[cmb69]

Description

Even with a minimal x86 debug build on Windows, as soon as OPcache is enabled, php.exe always triggers an assertion violation.

buildconf && configure --disable-all --enable-cli --disable-debug-pack --enable-debug --disable-zts --enable-opcache --enable-test-ini && nmake
nmake run ARGS=-v

outputs

Assertion failed: ((uintptr_t)(accel_shared_globals->interned_strings).start & 0x7) == 0, file ext\opcache\ZendAccelerator.c, line 2880

php-src/ext/opcache/ZendAccelerator.c

Line 2890 in bb35da3

ZEND_ASSERT(((uintptr_t)ZCSG(interned_strings).start & 0x7) == 0); /* should be 8 byte aligned */

Some relevant debug info:

&ZCSG(interned_strings)         0x200000c4
sizeof(zend_string_table)       0x18
hash_size+1                     0x80000
sizeof(zend_string_table_pos_t) 0x4
sizeof(zend_string)             0x14
ZCSG(interned_strings).start    0x2020017c

So it seems to me that sizeof(zend_string) doesn't meet the expectation of being a multiple of 8. No, the problem is more likely that &ZCSG(interned_strings) is not a multiple of 8.

I bisected this down to 1bae61a. @arnaud-lb, can you please clarify?

PHP Version

PHP 8.4

Operating System

Windows x86