[echoix]

Problem

The Docker builds in CI intermittently fail, and often pass on rerun. The make -j 4 step fails in python/grass/app with:

sed ... resource_paths.py > .../etc/python/grass/app/resource_paths.py
/bin/sh: 1: cannot create .../etc/python/grass/app/resource_paths.py: Directory nonexistent
make[5]: *** [Makefile:23: .../resource_paths.py] Error 2

python/grass/app is then not installed, so g.extension fails with ModuleNotFoundError: No module named 'grass.app.runtime', and the build exits with code 2.

Failing runs with this error: 37145943141, 37127864658 (passed on rerun), 37127518048.

Cause

The $(DSTDIR)/resource_paths.py rule redirects sed output into $(DSTDIR) but does not depend on it. With parallel make, the redirect can run before the mkdir -p for that directory (started for another target) has finished. The pattern rule for the other files already has | $(DSTDIR).

Fix

Add $(DSTDIR) as an order-only prerequisite of the resource_paths.py rule.

Testing

The race window is tiny, so it was reproduced and checked on a copy of python/grass/app/Makefile with the real Python.make and a slowed mkdir (MKDIR='sleep 1; mkdir -p', make -j8):

• Before the change: fails with the exact Directory nonexistent error above.
• After the change: builds successfully and installs all files (__init__.py, __main__.py, cli.py, data.py, runtime.py, resource_paths.py).

Without the slowed mkdir, neither version failed in 300 plain -j8 runs, which matches the intermittent behavior in CI.

The Docker workflow does not run on PRs that only touch this Makefile, so it was dispatched manually on this branch's fork: run 37152838494 built all four images (alpine, debian, ubuntu, ubuntu_wxgui) successfully. Since the failure is intermittent, one green run is supporting evidence. The Docker workflow runs on main after merge will provide more.

Developed with AI assistance (Claude Code).