Fix C++11 narrowing error on Mac OS

[dgerlanc]

Resolves #127

Previously, tests including the following would fail with the following errors:

FAILED tests/graph/test_compute_test_value.py::TestComputeTestValue::test_empty_elemwise - aesara.link.c.exceptions.CompileError: Compilation failed (return status=1):
FAILED tests/graph/test_compute_test_value.py::TestComputeTestValue::test_overided_function - aesara.link.c.exceptions.CompileError: Compilation failed (return status=1):
FAILED tests/graph/test_compute_test_value.py::TestComputeTestValue::test_scan_err1 - aesara.link.c.exceptions.CompileError: Compilation failed (return status=1):
FAILED tests/graph/test_compute_test_value.py::TestComputeTestValue::test_scan_err2 - aesara.link.c.exceptions.CompileError: Compilation failed (return status=1):

TODO: Add tests to verify modification of config.gcc__cxxflags

• [ ] No gcc_cxxflags
  • Darwin -> Add -Wno-c++11-narrowing
  • Other sys.platform -> No-Op
• [ ] Has gcc__cxxflags but no -Wno-c++11-narrowing
  • Darwin -> Add -Wno-c++11-narrowing and other flags preserved
  • Other platform -> other flags preserved
• [ ] Has gcc_cxxflags including -Wno-c++11-narrowing
  • All platforms -> gcc__cxxflags remain the same

[codecov[bot]]

Codecov Report

Merging #972 (40d12ff) into main (ead2c02) will decrease coverage by 0.02%. The diff coverage is 100.00%.

:exclamation: Current head 40d12ff differs from pull request most recent head 2bef458. Consider uploading reports for the commit 2bef458 to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #972      +/-   ##
==========================================
- Coverage   74.75%   74.73%   -0.02%     
==========================================
  Files         194      194              
  Lines       49896    49880      -16     
  Branches    10553    10550       -3     
==========================================
- Hits        37298    37278      -20     
- Misses      10270    10273       +3     
- Partials     2328     2329       +1     

Impacted Files	Coverage Δ
aesara/link/c/cmodule.py	52.32% <100.00%> (+0.27%)	:arrow_up:
aesara/tensor/__init__.py	95.55% <0.00%> (-0.75%)	:arrow_down:
aesara/tensor/math.py	90.42% <0.00%> (-0.27%)	:arrow_down:
aesara/scalar/basic.py	79.04% <0.00%> (-0.13%)	:arrow_down:
aesara/scalar/__init__.py	100.00% <0.00%> (ø)

[twiecki]

We do this by default in pymc: https://github.com/pymc-devs/pymc/blob/main/pymc/init.py#L36 it should be pretty safe to just always do that.

[dgerlanc]

I was going to make this a bit fancier by checking the existing flags gcc_cxxflags on a platform-dependent basis, and only adding the compatibility flags as necessary. I don't think it's an issue to have duplicate flags (if the user has already included them), but does add a bit of noise.

Still need to add tests to aesara whether we use the pymc code @twiecki linked to or my implementation. @brandonwillard Any preference?

[brandonwillard]

In general, we should try to apply OS/arch-specific settings only to said OS/arch's, whenever possible.

[dgerlanc]

I should probably check that we're on macOS and using the C backend. This probably doesn't apply with the numba backend.

Also, I need to add a test case for this.

@brandonwillard Is there an existing location for config-related test cases?

[brandonwillard]

@brandonwillard Is there an existing location for config-related test cases?

tests.test_config is for the general configuration classes, but there really isn't a place for testing specific config settings. Since this config setting is specific to C compilation, tests.link.c.test_basic is probably a suitable place.