Illegal instruction: illegal operand when compiling with -fsanitize=address (openmpi 5.0.5)

[muralidhar-nalabothula]

Background information

What version of Open MPI are you using? (e.g., v4.1.6, v5.0.1, git branch name and hash, etc.)

v 5.0.5

Describe how Open MPI was installed (e.g., from a source/distribution tarball, from a git clone, from an operating system distribution package, etc.)

Operating system distribution package (pacman -S openmpi)

Please describe the system on which you are running

• Operating system/version: EndeavourOS VERSION=2024.06.25
• Computer hardware: x86_64 (Intel(R) Core(TM) i7-8550U CPU @ 1.80GHz)

---

Details of the problem

When using address sanitizer, I get Illegal instruction. (same with both gcc and clang). Please note that I donot see this error when using 4.1.6 version. This issue was mentioned previously: #12584 (comment)

#include <mpi.h>
int main(int argc, char* argv[])
{
    MPI_Init(NULL,NULL);
    MPI_Finalize();
    return 0; 
}

mpicc -g -fsanitize=address sample_prog.c
 ./a.out
 # output:
 Caught signal 4 (Illegal instruction: illegal operand)
AddressSanitizer:DEADLYSIGNAL
=================================================================
==2532896==ERROR: AddressSanitizer: SEGV on unknown address 0x7368917f1000 (pc 0x7368917f1000 bp 0x736892049050 sp 0x736892049020 T0)
==2532896==The signal is caused by a READ memory access.
==2532896==Hint: PC is at a non-executable region. Maybe a wild jump?
    #0 0x7368917f1000  (<unknown module>)

AddressSanitizer can not provide additional info.
SUMMARY: AddressSanitizer: SEGV (<unknown module>) 
==2532896==ABORTING

'''gdb output```

[New Thread 0x7ffff36006c0 (LWP 2533116)]

Thread 1 "a.out" received signal SIGILL, Illegal instruction.
0x00007ffff78526b7 in mprotect () from /usr/lib/libasan.so.8

[rhc54]

I don't see anything usable in that error output - an "illegal instruction somewhere in the code" is impossible to track down. Any chance you can localize that a bit?

[bosilca]

The culprit seems to be mprotect () from /usr/lib/libasan.so.8, that's not something this community we can fix.