Make check-klayout an order-only prereq of merged GDS#4296
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maliberty merged 1 commit intoJun 17, 2026
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The phony check-klayout target was a normal prerequisite of $(GDS_MERGED_FILE), which forced the KLayout def2stream merge to re-run on every `make finish`/`make metadata` invocation regardless of whether the GDS inputs had changed. Moving it behind `|` keeps the KLayout availability check when the GDS needs building, without marking the GDS perpetually out-of-date. Signed-off-by: Matt Liberty <mliberty@precisioninno.com>
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This pull request updates the flow/Makefile to make check-klayout an order-only prerequisite for the $(GDS_MERGED_FILE) target. This prevents unnecessary rebuilds of the merged GDS file when the check-klayout target is executed. There are no review comments, and I have no additional feedback to provide.
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Problem
Running
make finish(ormake metadata, which depends onfinish) repeatedly re-runs the KLayoutdef2streamGDS merge every single time, even when nothing upstream changed.Root cause
The phony
check-klayouttarget was a normal prerequisite of$(GDS_MERGED_FILE):A phony prerequisite has no file on disk, so Make treats it as always newer than the target — forcing the merge recipe to run on every invocation regardless of timestamps. The re-merge then cascades into the
$(GDS_FINAL_FILE)copy and downstreamfinish/metadatawork.Fix
Move
check-klayoutbehind|so it's an order-only prerequisite. The KLayout availability check still runs when the GDS actually needs building, but its phony status no longer marks the GDS perpetually out-of-date.The
klayout_%viewer shortcuts at the othercheck-klayoutuse-site are intentionally left unchanged — those targets are themselves.PHONY(interactive viewers meant to run on demand).Verification
make finish -non an already-builtnangate45/gcd/baseno longer schedulesdo-gds-merged/def2stream, whereas before the fix it did on every run.