--------------
The developer is expected to write a makefile fragment, in each
-relevant subdirectory, called `Subdir.sd.mk'.
+relevant subdirectory, called `Dir.sd.mk'.
These fragments may contain ordinary make language. Unqualified
filenames are relative to the build toplevel, and all commands all run
`the build directory corresponding to this .sd.mk file', etc.
There are a variety of convenient constructions.
-The result is that to a large extent, the Subdir.sd.mk has an easy way
+The result is that to a large extent, the Dir.sd.mk has an easy way
to namespace its "local" make variables, and an easy way to refer to
its "local" filenames (and filenames in general).
-The Subdir.sd.mk's are filtered, fed through autoconf in the usual way
+The Dir.sd.mk's are filtered, fed through autoconf in the usual way
(for @..@-substitutions) and included by one autogenerated toplevel
makefile.
which exists purely to capture ordinary make invocations and arrange
for something suitable to happen.
-Where there are dependencies between subdirectories, each Subdir.sd.mk
+Where there are dependencies between subdirectories, each Dir.sd.mk
can simply refer to files in other subdirectories directly.
Invocation, "recursive" per-directory targets
subdirectory `src' has a target `src/all'. The rules for these are
automatically generated from the settings of the per-directory
&TARGETS variables. &TARGETS is magic in this way. (In
-src/Subdir.sd.mk, &TARGETS of course refers to a make variable called
+src/Dir.sd.mk, &TARGETS of course refers to a make variable called
src_TARGETS.)
The `all' target in a parent directory is taken to imply the `all'
The files Prefix.sd.mk and Suffix.sd.mk in the toplevel of the source
are automatically processed before and after each individual
-directory's Subdir.sd.mk, and the &-substituted contents therefore
+directory's Dir.sd.mk, and the &-substituted contents therefore
appear once for each subdirectory.
This lets you do per-directory boilerplate. Some useful boilerplate
&:include subdirmk/clean.sd.mk
For example you could put that in Suffix.sd.mk.
-The top-level Subdir.sd.mk is the first makefile included after the
+The top-level Dir.sd.mk is the first makefile included after the
autogenerated `main.mk' which merely has some basic settings and
includes. So if you want to get in early and set global variables,
-put them near the top of Subdir.sd.mk.
+put them near the top of Dir.sd.mk.
The file Final.sd.mk in the toplevel directory is processed and
included after all the other files.
------------------
If want to set global variables, such as CC, that should only be done
-once. You can put them in your top-level Subdir.sd.mk, or a separate
+once. You can put them in your top-level Dir.sd.mk, or a separate
file you `include' and declare using SUBDIRMK_MAKEFILES.
If you need different settings of variables like CC for different
subdirectories, you should probably do that with target-specific
variable settings. See the info node `(make) Target-specific'.
-Subdirectory templates `.sd.mk' vs plain autoconf templates `.mk.in'
+Directory templates `.sd.mk' vs plain autoconf templates `.mk.in'
--------------------------------------------------------------------
There are two kinds of template files.
Instantiated Usu. once per subdir Once only
- Need to be mentioned No, but Subdir.sd.mk All not in subdirmk/
+ Need to be mentioned No, but Dir.sd.mk All not in subdirmk/
in configure.ac? via SUBDIRMK_SUBDIRS via SUBDIRMK_MAKEFILES
How to include `&:include foo.sd.mk' `include foo.mk'
in all relevant .sd.mk in only one
- (but not needed for Subdir.sd.mk
+ (but not needed for Dir.sd.mk
Prefix, Suffix, Final)
If you `include subdirmk/regen.mk', dependency management and
(i) In the build tree, or in the source tree ?
- (ii) In (or relative to) the subdirectory to which this Subdir.sd.mk
+ (ii) In (or relative to) the subdirectory to which this Dir.sd.mk
relates, or relative to the project's top level ?
(iii) Absolute or relative pathname ? Usually relative pathnames
&:endm .. endef
NAME is processed for &
+&${..$..} => ${eval ${call ..$$..}}
+ (matches { } pairs to find the end)
+ content is $-doubled (unless it contains $- to turn that off)
+
+ Together &:macro and &${...} provide a more reasonable macro
+ facility than raw make. They solve the problem that make
+ expansions cannot directly generate multiple rules, variable,
+ etc.; instead, `$(eval )' must be used, but that re-expands
+ the argument, meaning that all the literal text must be
+ $-doubled. This applies to the macro text and to the
+ arguments. Also `$(eval $(call ...))' is an unfortunate syntax.
+ Hence &:macro and &${...}.
+
While dollar-doubling:
- - - - - - - - - - -
m4_include([subdirmk/subdirmk.ac])
SUBDIRMK_SUBDIRS([...list of subdirectories in relative syntax...])
-Write a Subdir.sd.mk in each directory. The toplevel one should
+Write a Dir.sd.mk in each directory. The toplevel one should
probably contain:
include subdirmk/usual.mk
-----
You can convert your project incrementally. Start with the top-level
-Makefile.in and rename it to Subdir.sd.mk, and add the appropriate
+Makefile.in and rename it to Dir.sd.mk, and add the appropriate
stuff to configure.ac, and fix everything up. Leave the existing
$(MAKE) -C for your existing subdirectories alone. Then you can
convert individual subdirectories, or classes of subdirectories, at
~ian / subdirmk.git / blobdiff