https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92257

            Bug ID: 92257
           Summary: AVX512 incorrect usage of aligned loads and stores
           Product: gcc
           Version: 9.2.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: ilya at alfs dot me
  Target Milestone: ---

Hello,

I had few segmentation faults while writing AVX512 code. SEGFAULTs were caused
by aligned loads used when data alignment can not be guaranteed in compile
time.

test.c:
#include <immintrin.h>

__m512i foo(__m512i *a) {
        return a[100];
}

gcc -S -O3 -march=icelake-client -mavx512f ./test.c

test.s:
        .file   "test.c"
        .text
        .p2align 4
        .globl  foo
        .type   foo, @function
foo:
.LFB5279:
        .cfi_startproc
        vmovdqa64       6400(%rdi), %zmm0
        ret
        .cfi_endproc
.LFE5279:
        .size   foo, .-foo
        .ident  "GCC: (GNU) 9.2.1 20190827 (Red Hat 9.2.1-1)"
        .section        .note.GNU-stack,"",@progbits

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