On Tue, Oct 26 2021, Jeff King wrote: > Since 8650c6298c (doc lint: make "lint-docs" non-.PHONY, 2021-10-15), we > put the output for gitlink linter into .build/lint-docs/gitlink. There > are order-only dependencies to create the sequence of subdirs like: > > .build/lint-docs: | .build > $(QUIET)mkdir $@ > .build/lint-docs/gitlink: | .build/lint-docs > $(QUIET)mkdir $@ > > where each level has to depend on the prior one (since the parent > directory must exist for us to create something inside it). But the > "howto" and "config" subdirectories of gitlink have the wrong > dependency; they depend on "lint-docs", not "lint-docs/gitlink". > > This usually works out, because the LINT_DOCS_GITLINK targets which > depend on "gitlink/howto" also depend on just "gitlink", so the > directory gets created anyway. But since we haven't given make an > explicit ordering, things can racily happen out of order. > > If you stick a "sleep 1" in the rule to build "gitlink" like this: > > ## Lint: gitlink > .build/lint-docs/gitlink: | .build/lint-docs > - $(QUIET)mkdir $@ > + $(QUIET)sleep 1 && mkdir $@ > > then "make clean; make lint-docs" will fail reliably. Or you can see it > as-is just by building the directory in isolation: > > $ make clean > [...] > $ make .build/lint-docs/gitlink/howto > GEN mergetools-list.made > GEN cmd-list.made > GEN doc.dep > SUBDIR ../ > make[1]: 'GIT-VERSION-FILE' is up to date. > SUBDIR ../ > make[1]: 'GIT-VERSION-FILE' is up to date. > mkdir: cannot create directory ‘.build/lint-docs/gitlink/howto’: No such file or directory > make: *** [Makefile:476: .build/lint-docs/gitlink/howto] Error 1 > > The fix is easy: we just need to depend on the correct parent directory. > > Signed-off-by: Jeff King <peff@xxxxxxxx> > --- > The problem starts in ab/fix-make-lint-docs, which is in master. > > I wasn't able to trigger the problem locally even with running 'make > clean; make lint-docs' in a loop, but I did see it in the wild in a CI > documentation job: > > https://github.com/peff/git/runs/4005766641?check_suite_focus=true#step:4:60 > > It would have been a lot easier to diagnose from the CI output if the > mkdir lines weren't silent. I.e., if we had a $(QUIET_MKDIR) which > printed "MKDIR $@" rather than nothing at all. > > Documentation/Makefile | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/Documentation/Makefile b/Documentation/Makefile > index 911b6bf79c..ed656db2ae 100644 > --- a/Documentation/Makefile > +++ b/Documentation/Makefile > @@ -472,9 +472,9 @@ print-man1: > ## Lint: gitlink > .build/lint-docs/gitlink: | .build/lint-docs > $(QUIET)mkdir $@ > -.build/lint-docs/gitlink/howto: | .build/lint-docs > +.build/lint-docs/gitlink/howto: | .build/lint-docs/gitlink > $(QUIET)mkdir $@ > -.build/lint-docs/gitlink/config: | .build/lint-docs > +.build/lint-docs/gitlink/config: | .build/lint-docs/gitlink > $(QUIET)mkdir $@ > LINT_DOCS_GITLINK = $(patsubst %.txt,.build/lint-docs/gitlink/%.ok,$(HOWTO_TXT) $(DOC_DEP_TXT)) > $(LINT_DOCS_GITLINK): | .build/lint-docs/gitlink Thanks a lot for fixing that bug, and sorry for not spotting it. This fix LGTM and is obviously correct. I'll try to do something about the $(QUIET*) as a follow-up, I was trying to find the right balance between over-verbosity & "tracing".
