Core Dump (Illegal Instruction)

[juliotux]

Issue:

• The build on Linux is causing Core Dump due to illegal instructions.
• Problem reported also in https://github.com/juliotux/astrometry-conda/issues/2
• Local build do not present any problem.

Debugging the stock package here, I got:

(astrometry) [julio@Dell7995 ~]$ gdb --args solve-field '/home/julio/Downloads/1_08D69jNUsgFzJZAvtsT5Hw.jpeg' 
...
Thread 1 "solve-field" received signal SIGILL, Illegal instruction.
main (argc=2, args=0x7fffffffe0e8) at solve-field.c:996
996 solve-field.c: No such file or directory.
...

Witch points to a memset function. https://github.com/dstndstn/astrometry.net/blob/97153471255c54b954e9fc4b9b191033cb9fa520/blind/solve-field.c#L996

However, I could not get layout asm of the debug, that returned:

Multi-thre Thread 0x7ffff506a7 In:                                 L??   PC: ??/home/conda/feedstock_root/build_artifacts/astrometry_1584289740927/_build_env/x86_64-conda_cos6-linux-gnu/sysroot/usr/include/bits/string3.h: No such file or directory.

So I couldn't find what illegal instruction happend.

[dstndstn]

Thanks for digging into this. We don't use BLAS directly, though gsl is used. If a system gsl is available, we use that (see SYSTEM_GSL in Makefile and util/makefile.gsl); otherwise, we use a vendored subset, in gsl-an (looks like we've currently got v 1.16).

As previously mentioned, architecture-specific flags (including preventing any defaults) can be set with the ARCH_FLAGS= environment variable).

You can also turn off optimization flags via OPTIMIZE=no . All this happens in util/makefile.common

To really dig into this, I would need to know:

• /proc/cpuinfo
• gcc --version
• build log, showing the compile command lines it's running during compile and link phases

It will also build on clang or icc if that's an option :)

And note that only setting CFLAGS is NOT sufficient; ARCH_FLAGS still get auto-detected.

[juliotux]

Thanks @dstndstn

My new test with manual setting generic arch flags in #9 it looks that the problem is solved. But this can be considered just a temporary solution. I will make more tests later, but all the log builds and system info are located in the conda-forge CI:

https://dev.azure.com/conda-forge/feedstock-builds/_build/results?buildId=131361&view=results

This correspond to the following recipe build: https://github.com/conda-forge/astrometry-feedstock/blob/47ed8e35a87aa0083134c15b898dd5d45f0fcb37/recipe/build.sh

[dstndstn]

Okay, that's great. If you need any changes to the astrometry.net code to address this, or make it easier to handle, please let me know. Thanks again for your work here.

[juliotux]

With the new build configs it seems to be solved.