CODEWITHSUNDEEP
makefile
Brent.Longborough
Brent.Longborough

Reputation: 9775

Make - How can I define a generic pattern for extensionless files

I'm experimenting with some semi-literate programming, and need to build some files that have no .extension. I'd like to use a generic patter in my Makefile, but can't get it to work.

Here's my Makefile, reduced to an MWE:

all: jcb jcbsetup
jcbsetup: jcb.org
%.: %.org
    ./weborg2asm.awk $< > $@

In this case, make -B says "nothing to be done"

If I try changing %.: to % :, it builds only jcb, not jcbsetup.

Obviously, I can code the recipe for each explicit target, but for obvious reasons I'd like to use a pattern. I can (sort of) understand why this doesn't work, but is there something that does work?

I'm using Gnu Make 4.0, under cygwin.

Upvotes: 0

Views: 112

Answers (1)

Norman Gray
Norman Gray

Reputation: 12514

As shown, this shows how to build jcb. from jcb.org, and says nothing about jcb.

If (as looks correct) you change the rule to %: %.org then that would appear to do the correct thing, and your makefile is doing what you asked.

Note that your target jcbsetup: jcb.org doesn't have any actions, and therefore it's saying that "when jcb.org is made, then jcbsetup is up-to-date, too", and it won't do anything extra to make jcbsetup.

If you have a jcbsetup.org, then the %: %.org would match, and this would indicate how to create jcbsetup from jcbsetup.org. But this would happen only in this case.

Note that it's usual for the pattern rules (involving %) to go before the first concrete rule; they may not be recognised afterwards (even if they are, it's more conventional/readable for them to go first).

Upvotes: 1

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