PyTensor fails to compile model after upgrading to mac OS 15.4

Questions v5
21

Is this a new conda env?

Have you tried that this?

import pytensor
pytensor.config.cxx = '/usr/bin/clang++'
22

Yes, new env, and have that.

23

Wow, so new env, you’ve followed the steps here, and none of this worked??

24

Yes, any idea on the error info above?

/.pytensor/compiledir_macOS-15.4-arm64-arm-64bit-arm-3.10.16-64/tmp_71um3ky/mod.cpp:496:9: error: non-constant-expression cannot be narrowed from type 'ssize_t' (aka 'long') to 'int' in initializer list [-Wc++11-narrowing]
2025-04-10 17:10:25|CRITICAL|log:182|log_lines():   496 |         V5_stride0, V5_stride1, V5_stride2,
25

This doesn’t look like the error we were talking about. Can you share the code and exact steps that lead to this please? Otherwise it’s hard to help out

26

Try adding the following block to your .pytensorrc file:

[gcc]
cxxflags = -Wno-c++11-narrowing
2 Likes
27

Sorry, I’m unable to share the exact code… the full error messages are listed above, and it happened when I called nutpie.sample().

28

Thanks for the suggestion, where does .pytensorrc file locate?

29

Here

1 Like
30

" Try adding the following block to your .pytensorrc file:

[gcc]
cxxflags = -Wno-c++11-narrowing

"

This works for me!! Thank you, and thanks to everyone providing help!!

1 Like
31

I found the

import pytensor
pytensor.config.cxx = '/usr/bin/clang++'

works perfectly for me. But I also have code that I run on Mac and Linux (where I don’t have the problem) - so adding my solution below for when you are running code in Mac and Linux environments:

import platform

if platform.system() == 'Darwin': # you are on a mac, set up the correct compiler. If not, you are OK
    import pytensor
    pytensor.config.cxx = '/usr/bin/clang++'
1 Like
32

Legend, this works as a good temp fix for me.

33

This is exactly the case where you should be setting the config via .pytensorrc

34

Yeap, you are right, implementing it now!

1 Like
35

Just chiming in – I had similar clang++ flavored error on two different Intel Macs.

On one Mac, adding pytensor.config.cxx = '/usr/bin/clang++' to the script and/or the .pytensorrc file didn’t work, but reinstalling the command line tools and rolling back to python 3.10 with a fresh environment ended up working fine.

On the other Mac, none of the above options worked, but step 5 from @jessegrabowski ‘s April 9th comment, conda remove-ing everything that conda list clang turned up, did the trick.

Thanks for the help!

1 Like
36

omg thank you so much, i used chatgpt and tried to fix this problem for like an hour, and your code just fixed it in one sec, i literally signed up a new account for this site just to say THANK YOU SO MUCH