SUMMARY valgrind memcheck 3.25.1 errors on AMD Ryzen 9 7950X3D STEPS TO REPRODUCE 1. get AMD Ryzen 9 7950X3D or equivalent Zen 4 CPU. 2. compile program with GCC version 14.3.0, option "-march=native", "-O2" or "-O0". A simple C program like "int main(void) { return 0; }" is sufficient, because the program start breaks in glibc. 3. compile glibc with GCC version 14.3.0, option "-march=native -ggdb -Og" 4. execute program with valgrind memcheck OBSERVED RESULT vex amd64->IR: unhandled instruction bytes: 0x62 0xF1 0x7F 0x48 0x7F 0x84 0x24 0x20 0x0 0x0 vex amd64->IR: REX=0 REX.W=0 REX.R=0 REX.X=0 REX.B=0 vex amd64->IR: VEX=0 VEX.L=0 VEX.nVVVV=0x0 ESC=NONE vex amd64->IR: PFX.66=0 PFX.F2=0 PFX.F3=0 ==12277== valgrind: Unrecognised instruction at address 0x4023a7d. ==12277== at 0x4023A7D: _dl_start (rtld.c:565) ==12277== by 0x40215C7: ??? (in /lib64/ld-linux-x86-64.so.2) EXPECTED RESULT memcheck the program SOFTWARE/OS VERSIONS Gentoo Linux. Kernel 6.12.40 64bit ADDITIONAL INFORMATION workaround exists with gcc option "-march=znver3 -mtune=znver4". option "-march=znver4" does not work
This op code is vmovdqu8 ZMMWORD PTR [rsp-0x6fffffe0],zmm0 which is AVX512. *** This bug has been marked as a duplicate of bug 383010 ***