Core package Makefiles declare no phony targets, so a same-named file can silently skip a build step #3709

The four Makefiles under packages/core/ define their own targets and declare none of them phony. installer, platform, flux-aio and testing include only hack/common-envs.mk, which defines no targets, so nothing declares anything on their behalf either. All four are reached from the root Makefile build: target.

The failure is quiet. image: in the installer reads image: pre-checks image-operator image-packages chart, and chart: has a recipe and no prerequisites. Put a file or directory named chart next to that Makefile and make treats the target as up to date, skips the helm packaging step and exits 0 — a green build that packaged nothing. The same shape covers show, apply, diff, delete, help, test and unprotect across the four files.

Nothing collides today. No file or directory named after any of those targets exists under packages/core/, so this is preventive rather than a fix for present breakage.

The remedy is one .PHONY: line per file, naming the targets that file defines. It cannot be done centrally, and that is the point worth recording: hack/common-envs.mk does not define these targets, and naming a target in .PHONY that the including file does not define creates it as an empty target, turning a missing rule from No rule to make target (exit 2) into Nothing to be done (exit 0). #3353 closes the same class for the 159 package Makefiles that include hack/package.mk, and stops at the targets that file actually defines for exactly this reason.