I stand to be corrected however, no. Not a direct answer to your question but in my experience, the best way is to approach such situations is to let Make figure out what depends on what, should it make a particular target or not and to avoid `if' and `define' as much as possible.
-- Bahman On Tue, 2023-09-26 at 16:30 +0000, Ed L Wolf wrote: > The problem is that $(eval SUPPLIER_A2l := $(sort $(shell find > $(DIR_A2LGEN_SUPPLIER) -type f -name "*.a2l"))) runs before the > directory was created and the a2l files were copied to the directory. > Since this ran before the directory creation and copy of the a2l > file SUPPLIER_A2L is always null. IS there anyway to force this > statement to be ran in the exact sequence its listed? > > Ed L Wolf > Technical Advisor - Embedded Software > e.l.w...@cummins.com > Cummins Inc. > Mail Code: C7004 > 1460 National Road > Columbus, Indiana 47201 > United States > > -----Original Message----- > From: Bahman Movaqar <bah...@bahmanm.com> > Sent: Tuesday, September 26, 2023 12:11 PM > To: Ed L Wolf <e.l.w...@cummins.com>; bug-make@gnu.org > Subject: Re: Problem setting a variable inside a target > > EXTERNAL SENDER: This email originated outside of Cummins. Do not > click links or open attachments unless you verify the sender and know > the content is safe. > > > OK, it took me a while but I think I may have something relatively > more readable. > > The idea is to let Make handle the prerequisites and the order of > build for you by using well laid out targets. > > The challenge I was facing trying to understand your code was that > you'd condensed the original hierarchy of `*.a2l' files into > `DIR_A2LGEN_SUPPLIER' which had made very difficult to tell Make how > to make a target and when. > > Here's my further slimmed down version of your snippet. Let me know > if that makes sense and whether it solves your problem. You can also > view on pastebin w/ syntax highlighting: > https://pastebin.com/cHy8CuUt > > > 🙶 > > SHELL := /usr/bin/env -S bash -o pipefail .DEFAULT_GOAL := all > > ##################################################################### > ## > > ROOT := $(dir $(abspath $(lastword $(MAKEFILE_LIST)))) build.dir := > $(ROOT)build/ src.dir := $(ROOT) > > ##################################################################### > ## > > A2L-files.src = $(shell find $(src.dir) -type f -name '*.a2l') A2L- > files.dst = $(subst $(src.dir),$(build.dir),$(A2L-files.src)) > > ##################################################################### > ## > > $(build.dir) : > mkdir -p $(@) > > ##################################################################### > ## > > $(build.dir)%.a2l : $(src.dir)%.a2l > mkdir -p $(build.dir)$(subst $(src.dir),,$(dir $(<))) \ > && cp $(<) $(@) > > ##################################################################### > ## > > .PHONY : merge > > ifneq ($(A2L-files.dst),) > > merge : $(A2L-files.dst) > @echo MERGE POSSIBLE > @echo ... > > else > > merge : > @echo MERGE NOT POSSIBLE > @echo ... > > endif > > ##################################################################### > ## > > .PHONY : clean > > clean : > -rm -rf $(build.dir) > > ##################################################################### > ## > > .PHONY : all > > all : | $(build.dir) > all : merge > > 🙷 > > > -- > Bahman > > > On Tue, 2023-09-26 at 12:17 +0000, Ed L Wolf wrote: > > Here is the strip down version > > > > $(DIR_A2LGEN_SETUP)/McData-setup.a2l: > > @echo "A2L $@" > > > > > > @find $(DIR_BSWPROJECT) -type f -name "*.a2l" | xargs - > > i > > cp {} $(DIR_A2LGEN_SETUP) > > > > > > > > > > ifneq ($(wildcard $(DIR_SUPPLIER)),) > > @find $(DIR_SUPPLIER) -type f -name "*.a2l" | xargs -i > > cp > > {} $(DIR_A2LGEN_SUPPLIER) > > $(eval SUPPLIER_A2l := $(sort $(shell find > > $(DIR_A2LGEN_SUPPLIER) -type f -name "*.a2l"))) > > @echo "A2L Supplier folder detected" > > @echo "Supplier a2l $(SUPPLIER_A2l)" > > > > > > # Just becuase there is a supplier folder does not mean it has a2l > > files. > > ifeq ($(SUPPLIER_A2l),"*.a2l") > > @echo "A2L Supplier a2l files > > found" > > > > else > > @cp $(DIR_A2LGEN_SETUP)/McData-copyright-can.a2l > > $(DIR_A2LGEN_SETUP)/McData-setup.a2l > > @echo "A2L Supplier folder detected but no a2l > > files present" > > endif > > > > else > > @cp $(DIR_A2LGEN_SETUP)/McData-copyright-can.a2l > > $(DIR_A2LGEN_SETUP)/McData-setup.a2l > > @echo "A2L Supplier folder not available" > > endif > > > > Ed L Wolf > > Technical Advisor - Embedded Software > > e.l.w...@cummins.com > > Cummins Inc. > > Mail Code: C7004 > > 1460 National Road > > Columbus, Indiana 47201 > > United States > > > > -----Original Message----- > > From: Bahman Movaqar <bah...@bahmanm.com> > > Sent: Tuesday, September 26, 2023 6:35 AM > > To: Ed L Wolf <e.l.w...@cummins.com>; bug-make@gnu.org > > Subject: Re: Problem setting a variable inside a target > > > > EXTERNAL SENDER: This email originated outside of Cummins. Do not > > click links or open attachments unless you verify the sender and > > know > > the content is safe. > > > > > > On Sun, 2023-09-24 at 17:23 +0000, Ed L Wolf wrote: > > > > > > > > ifneq ($(wildcard $(DIR_SUPPLIER)),) ... > > > > $(eval SUPPLIER_A2l := $(sort $(shell find > > > > $(DIR_A2LGEN_SUPPLIER) > > > > - > > > > type f -name "*.a2l"))) > > > ... > > > ifeq ($(SUPPLIER_A2l),"*.a2l") > > > > > > > Quickly skimming through your code, I can see that the above > > `ifneq' > > and `ifeq' are evaluated at the very same time/pass. That means > > the > > result of `eval' will not be visible to `ifeq'. > > > > HTH, > > > > > > PS: I could have tried to come up w/ an alternative approach to > > laying > > out the code but, I found the snippet crowded w/ too much logic > > specific to your case which makes it hard for me to see the > > abstract > > patterns in play. Can you try to slim down the snippet and push it > > to > > a public repo somewhere so I can take a look? > > > > -- > > Bahman
