Crash micropython in pairheap.h

Hello Team,

Can you help us to identify why this crash appears or what we can do to avoid it? (ESP32 micropython port)

assertion "node->child == NULL && node->next == NULL" failed: file "../../py/pairheap.h", line 88, function: mp_pairheap_push
abort() was called at PC 0x40178577 on core 0

ELF file SHA256: 0000000000000000

Backtrace: 0x40095138:0x3ffce620 0x4009556d:0x3ffce640 0x40178577:0x3ffce660 0x400ef1c2:0x3ffce690 0x400e4136:0x3ffce6b0 0x400dfe71:0x3ffce6e0 0x400dffad:0x3ffce700 0x400ee07f:0x3ffce720 0x400e41f8:0x3ffce7c0 0x400dfe71:0x3ffce7f0 0x400edff9:0x3ffce810 0x400e41f8:0x3ffce8b0 0x400dfe71:0x3ffce920 0x400dffad:0x3ffce940 0x400ee07f:0x3ffce960 0x400e41f8:0x3ffcea00 0x400dfe71:0x3ffcea70 0x400dfe9a:0x3ffcea90 0x400dff0b:0x3ffceab0 0x400eb251:0x3ffceb40 0x400eb597:0x3ffceb70 0x400e0032:0x3ffcec50 0x400ee339:0x3ffcec90 0x400e41f8:0x3ffced30 0x400dfe71:0x3ffced90 0x400dfe9a:0x3ffcedb0 0x40107d1a:0x3ffcedd0 0x40107ede:0x3ffcee60 0x400f79bd:0x3ffceeb0 0x40095b61:0x3ffceee0

looking into the pairheap.h:

// Push new node onto existing heap.  Returns the new heap.
static inline mp_pairheap_t *mp_pairheap_push(mp_pairheap_lt_t lt, mp_pairheap_t *heap, mp_pairheap_t *node) {    
                 assert(node->child == NULL && node->next == NULL);    
                 return mp_pairheap_meld(lt, node, heap); // node is first to be stable
}

What means "push a new node"? This is related with uasyncio? (We are using uasyncio)

Thanks for help us.

Start with py/pairheap.h, especially the assertion at line 88 in mp_pairheap_push, and review how the ESP32 MicroPython port uses it with uasyncio. Use the supplied backtrace and a reproducible workload to identify why a pushed node already has child or next links. Done means documenting the cause and a supported way to avoid the crash.