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Features of interest: Allow setting target local variables (similar to gmake) In META_MODE .MAKE.META.CMP_FILTER can be used for filtering commands before comparion. contrib/bmake/mk/cc-wrap.mk is an example of using these See ChangeLog for the gory details.
52 lines
1.1 KiB
Makefile
52 lines
1.1 KiB
Makefile
# $NetBSD: directive-ifdef.mk,v 1.5 2022/01/23 21:48:59 rillig Exp $
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#
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# Tests for the .ifdef directive, which evaluates bare words by calling
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# 'defined(word)'.
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DEFINED= defined
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# There is no variable named 'UNDEF', therefore the condition evaluates to
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# false.
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.ifdef UNDEF
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. error
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.endif
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# There is a variable named 'DEFINED', so the condition evaluates to true.
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.ifdef DEFINED
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.else
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. error
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.endif
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# Since a bare word is an abbreviation for 'defined(word)', these can be
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# used to construct complex conditions.
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.ifdef UNDEF && DEFINED
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. error
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.endif
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.ifdef UNDEF || DEFINED
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.else
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. error
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.endif
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# It looks redundant to have a call to defined() in an .ifdef, but it's
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# possible. The '.ifdef' only affects bare words, not function calls.
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.ifdef defined(DEFINED)
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.else
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. error
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.endif
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# String literals are handled the same in all variants of the '.if' directive,
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# they evaluate to true if they are not empty, therefore this particular
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# example looks confusing and is thus not found in practice.
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.ifdef ""
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. error
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.else
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.endif
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# Whitespace counts as non-empty as well.
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.ifdef " "
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.else
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. error
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.endif
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all: .PHONY
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