On Thu, Feb 12, 2026 at 10:47:37PM +0000, sagitter--- via devel wrote: > Hi all. > > I'm really sorry, i need to resend this mail again. > > I need help with recent MUMPS-5.8.* releases (not in Fedora) that produces > segmentation fault by running its example files. > I created the RPMs > (https://copr.fedorainfracloud.org/coprs/sagitter/ForTesting/build/10125628/) > including the files for testing. > > Debugging the previous release 5.8.1, Valgrind produces something like this > > $ mpirun -np 2 valgrind --tool=memcheck -s ./c_example > ==34094== Memcheck, a memory error detector > ==34094== Copyright (C) 2002-2024, and GNU GPL'd, by Julian Seward et al. > ==34094== Using Valgrind-3.25.1 and LibVEX; rerun with -h for copyright info > ==34094== Command: ./c_example > ==34094== > ==34095== Memcheck, a memory error detector > ==34095== Copyright (C) 2002-2024, and GNU GPL'd, by Julian Seward et al. > ==34095== Using Valgrind-3.25.1 and LibVEX; rerun with -h for copyright info > ==34095== Command: ./c_example > ==34095== > vex amd64->IR: unhandled instruction bytes: 0x6 0x0 0x0 0x0 0x0 0x0 0x0 0xD9 > 0x6 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
I tried disassembling this using https://defuse.ca/online-x86-assembler.htm (you have to turn 0x6 -> 0x06 etc). However it's unable to disassemble them: Disassembly Raw Hex (zero bytes in bold): 06000000000000D90600 String Literal: "\x06\x00\x00\x00\x00\x00\x00\xD9\x06\x00" Array Literal: { 0x06, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xD9, 0x06, 0x00 } Disassembly: 0: 06 (bad) 1: 00 00 add BYTE PTR [rax],al 3: 00 00 add BYTE PTR [rax],al 5: 00 00 add BYTE PTR [rax],al 7: d9 06 fld DWORD PTR [rsi] 9: 00 .byte 0x0 However this kind of valgrind error can happen because the code is using certain AVX512 instructions that valgrind hasn't implemented yet. You might try to recompile the program using: -mno-avx512f -mno-gfni (assuming that the MUMPS compiler can add C compiler flags? It's been nearly 40 years since I used MUMPS.) I'm not sure whether to believe the rest of the valgrind messages until this error is fixed. Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming and virtualization blog: http://rwmj.wordpress.com virt-top is 'top' for virtual machines. Tiny program with many powerful monitoring features, net stats, disk stats, logging, etc. http://people.redhat.com/~rjones/virt-top -- _______________________________________________ devel mailing list -- [email protected] To unsubscribe send an email to [email protected] Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/[email protected] Do not reply to spam, report it: https://forge.fedoraproject.org/infra/tickets/issues/new
