OK, forget all what I said about temperature - now it hanged at 62"C (active cooling) but always at the same compilation progress.
Sep 17 07:38:41 opi4 kernel: oom_kill_process+0x130/0x2d8
Sep 17 07:38:41 opi4 kernel: out_of_memory+0xe0/0x59c
Sep 17 07:38:41 opi4 kernel: __alloc_pages+0xc40/0xe48
The default trip points are working well.
Sorry for disturbing 😗