From 83f71e7cebb887d19b7ef2098e520d54129324c6 Mon Sep 17 00:00:00 2001 From: "Yann E. MORIN" Date: Mon, 1 Aug 2022 22:42:27 +0200 Subject: [PATCH] Makefile: fix show-vars for good this time Commit 5c54c3ef3db2 (Makefile: workaround make 4.3 issue for 'printvars and 'show-vars') did not fully fix the show-vars case, which still segfaults. Overall, show-vars generates a JSON blurb. That is supposed to be machine-readable, so we do not care that the variables are sorted, so we get rid of it to (slightly) simplify the code. Then, we currently iterate twice on the list of variables: the first one to filter-out the 'internal' variables, and the second one to filter only the variables matching the pattern. We can do away by iterating only once, and applying both filters at once. Since we now have an 'and' condition, we can take advantage of it: when none of the items in $(and) are empty, $(and) evaluates to the last item, while it evaluates to empty if any of the items is empty. So we can coalesce the $(if) and $(and) together: $(if $(and a,b),c) is equivalent to: $(and a,b,c) ; this gains us one parentheses depth. Finally, the cause for the segfault is an overly-long call to $(info). Reducing that is not easy: we want to call clean-json on the whole of the JSON blurb, so we can't emit the individual variables one by one, or the trailing comma would not be trimmed away. So, we go crazy: we just output each word from clean-json with $(info). We can do that, because mk-json-str transforms all spaces in a string to an escaped UTF-8 sequence, so we will never have spaces in values; the keys are the variables, so they won't have spaces either; spaces in the rest of the JSON blurb are totally optional, so we don't care how many there are. We know there are spaces, because we explicitly introduce some (after "expanded" or "raw", for example), so we should never hit a too-big word for $(info) to print. Thanks to Henri for the suggestion to push $(info) further inside the macro. Reported-by: Quentin Schulz Signed-off-by: Yann E. MORIN Cc: Roosen Henri Cc: Arnout Vandecappelle (Essensium/Mind) Cc: Thomas Petazzoni Tested-by: Quentin Schulz Signed-off-by: Thomas Petazzoni --- Makefile | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) diff --git a/Makefile b/Makefile index a743e42f91..07b594ea8a 100644 --- a/Makefile +++ b/Makefile @@ -1073,17 +1073,24 @@ printvars: show-vars: VARS?=% show-vars: @: - $(info $(call clean-json, { \ + $(foreach i, \ + $(call clean-json, { \ $(foreach V, \ - $(sort $(foreach X, $(.VARIABLES), $(filter $(VARS),$(X)))), \ - $(if $(filter-out environment% default automatic, $(origin $V)), \ + $(.VARIABLES), \ + $(and $(filter $(VARS),$(V)) \ + , \ + $(filter-out environment% default automatic, $(origin $V)) \ + , \ "$V": { \ "expanded": $(call mk-json-str,$($V))$(comma) \ "raw": $(call mk-json-str,$(value $V)) \ }$(comma) \ ) \ ) \ - } )) + } ) \ + , \ + $(info $(i)) \ + ) .PHONY: clean clean: