[Bug] Unable to compile addons with GRASS in conda

[petrasovaa]

Describe the bug

When GRASS is installed via conda, the include/Make/Platform.make file contains hardcoded absolute paths to compilers from the build environment. For example:

CC = /home/conda/feedstock_root/build_artifacts/grass_1768323359793/_build_env/bin/x86_64-conda-linux-gnu-cc

These paths do not exist on the user's system, causing g.extension to fail when attempting to compile addons:

/bin/sh: line 1: /home/conda/feedstock_root/build_artifacts/grass_1768323359793/_build_env/bin/x86_64-conda-linux-gnu-cc: No such file or directory

While this may need to be addressed in https://github.com/conda-forge/grass-feedstock, I opened it here for more visibility and in case there is something in GRASS itself that can be fixed.

[sakirr05]

hey @petrasovaa I've been looking into this and it seems related to compiler paths coming from Platform.make for Make-based builds, the CMake code path in g.extension already handles this (around lines 2074–2075) by checking CC/CXX in the environment and validating the compiler. The Make-based path doesn’t appear to do a similar check and ends up using whatever is defined in Platform.make.

One option could be to add similar validation to the Make path: check whether the configured compiler exists and fall back to system compilers if not. This would also cover Nix, Spack, and other cases where paths may get baked in at build time.

I can put together a PR if this seems reasonable, but wanted to check first in case there’s a better or preferred approach.
(And yes, agreed there’s probably also a conda-forge-side fix needed as you mentioned, but this would provide a fallback for any packaging system.)

[nilason]

Probably this should be addressed in the conda recipe. The generated Platform.make should be patched on installation, replacing build time prefix to run time prefix. Perhaps https://github.com/conda/conda-prefix-replacement can be used?
cc @HuidaeCho