SIGSEGV, Segmentation fault with memcpy_avx_unaligned

Question

I am trying to copy 4 bytes form s to handler->data didn't understand the error.

Tried to debug with gdb, but everything looks good.

memcpy(handler->data + handler->len, s->begin, num_bytes);   
(gdb) p handler->data   
$5 = (uint8_t *) 0x0   
(gdb) p s->begin   
$6 = (const uint8_t *) 0x7ffcfda705b2 "D"   
(gdb) s  
__memcpy_avx_unaligned () at ../sysdeps/x86_64/multiarch/memcpy-avx-unaligned.S:41 41     
../sysdeps/x86_64/multiarch/memcpy-avx-unaligned.S: No such file or directory.

score -1 · Answer 1 · answered Aug 28 '20 at 14:57

-1

I found the issue. I failed to initialize this handler->data.

answered Aug 28 '20 at 14:57

Nabz C

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And that is _obvious_ from the `p handler->data` in your GDB output (copying to `NULL` pointer isn't going to end well). – Employed Russian Aug 28 '20 at 18:45
Right, I have a weak understanding of pointers, so didn't think initially that was an issue. – Nabz C Aug 29 '20 at 20:26

SIGSEGV, Segmentation fault with memcpy_avx_unaligned

1 Answers1