[BUG] Program crash with mojo 24.3.0 (9882e19d)

[mortax]

Bug description

i have a small program that worked perfectly using mojo 24.2.1 but crashes (segmentation fault) when compiled with mojo 24.3.0`.

it's interesting to note that the previous executable is quite a bit larger than the current one:

• older (working) binary: 578872
• new (crashing) binary: 305912

Steps to reproduce

• Include relevant code snippet or link to code that did not work as expected.

the hard thing for me is that i would prefer to not share the code (at least for the foreseeable future).

• If using the Playground, name the pre-existing notebook that failed and the steps that led to failure.

i will have a look at Playgrounds to see if they can help me.

• Include anything else that might help us debug the issue.

i was able to generate a core dump. i'm happy to look at that myself -- or pass it along (it is, off course, huge!).

System information

• On what OS did you do install Mojo?

Architecture:       arm64

ProductName:        macOS
ProductVersion:     14.4.1
BuildVersion:       23E224

• Provide version information for Mojo by pasting the output of mojo -v

mojo 24.3.0 (9882e19d)

• Provide Modular CLI version by pasting the output of modular -v

modular 0.7.4 (df7a9e8b)

[JoeLoser]

Can you provide the source code by chance? That'll be the easiest to figure out what the problem is and a solution.

[mortax]

thanks @JoeLoser. i should probably note that the crashing program performs a fairly large recursive calculation. i'm investigating whether i can provide some version of the source code. if so, i would only be comfortable doing that privately.

in the meantime, i tried using a Playground and it only indicates that the program failed. i also found that running the program using mojo run provides slightly more information:

[2950:31950374:20240505,123447.014769:WARNING in_range_cast.h:38] value -634136515 out of range
[2950:31950377:20240505,123447.041191:ERROR directory_reader_posix.cc:42] opendir /Users/jrd/.modular/crashdb/attachments/d8457116-9460-4fec-8387-c5b9c232eaeb: No such file or directory (2)
[2950:31950374:20240505,123447.041235:WARNING crash_report_exception_handler.cc:257] UniversalExceptionRaise: (os/kern) failure (5)
zsh: illegal hardware instruction  source/recursive/program.mojo 1 3999999
{132} [univac]$ 

the crash above happens at/during the next recursive all. let me know is that helps at all.

i am also happy to provide one (or more) of these:

[univac]$ ls -lt /Users/jrd/.modular/crashdb/completed/* | head -1
-rw-------@ 1 jrd  staff  176557824 May  5 12:44 /Users/jrd/.modular/crashdb/completed/dca35d71-fa5e-497b-8b7e-a37bd0b312f0.dmp
[univac]$ file /Users/jrd/.modular/crashdb/completed/dca35d71-fa5e-497b-8b7e-a37bd0b312f0.dmp
/Users/jrd/.modular/crashdb/completed/dca35d71-fa5e-497b-8b7e-a37bd0b312f0.dmp: Mini DuMP crash report, 8 streams, Sun May  5 19:44:10 2024, 0 type

---

aside - i find this amusing:

[2950:31950377:20240505,123447.041191:ERROR directory_reader_posix.cc:42] opendir /Users/jrd/.modular/crashdb/attachments/d8457116-9460-4fec-8387-c5b9c232eaeb: No such file or directory (2)

because mkdir -p /Users/jrd/.modular/crashdb/attachments fixed it:

[3766:31966598:20240505,124410.952548:WARNING in_range_cast.h:38] value -634136515 out of range
[3766:31966598:20240505,124411.031207:WARNING crash_report_exception_handler.cc:257] UniversalExceptionRaise: (os/kern) failure (5)
zsh: illegal hardware instruction (core dumped)  source/recursive/program.mojo 1 3999999

[mortax]

@JoeLoser i guess that doesn't help.