Zephyr 3.7.0-rc1 issue: heap failure

[RobMeades]

I'm testing the move from 3.6.0 to 3.7.0 and one of our tests (running on an STM32F7), which has run happily for years on Zephyr (3.6.0 and earlier), Linux, Windows, etc, is now failing when it tries to free a memory block:

E: ***** BUS FAULT *****
E:   Imprecise data bus error
E: r0/a1:  0x20028400  r1/a2:  0x00002dbf  r2/a3:  0x00003fff
E: r3/a4:  0x00003fff r12/ip:  0x200142e0 r14/lr:  0x0806adc1
E:  xpsr:  0x81000000
E: r4/v1:  0x20028400  r5/v2:  0x0000059b  r6/v3:  0x00002cd8
E: r7/v4:  0x2002b0d8  r8/v5:  0x00000000  r9/v6:  0x00000000
E: r10/v7: 0x00000000  r11/v8: 0x00000000    psp:  0x20051f08
E: EXC_RETURN: 0xfffffffd
E: Faulting instruction address (r15/pc): 0x0806aea6
E: >>> ZEPHYR FATAL ERROR 26: Unknown error on CPU 0
E: Current thread: 0x20021b90 (main)
### Dumping current thread (main) ###
    0x0806aea6: free_chunk                   /home/zephyr_native-v3.7.0-rc1/zephyr/lib/heap/heap.c:144 (discriminator 1)
    0x0806adbc: free_list_remove             /home/zephyr_native-v3.7.0-rc1/zephyr/lib/heap/heap.c:64
    0x08042e2c: sys_heap_free                /home/zephyr_native-v3.7.0-rc1/zephyr/lib/heap/heap.c:197
    0x08056bf6: k_heap_free                  /home/zephyr_native-v3.7.0-rc1/zephyr/kernel/kheap.c:153
    0x08077a96: k_free                       /home/zephyr_native-v3.7.0-rc1/zephyr/kernel/mempool.c:54

Has anyone else seen anything like this and are there any heap debug options (guards etc.) in Zephyr that would help us track down what's going on?

[ajarmouni-st]

@RobMeades I think it would be better to open a bug issue.