It is possible to define the
SUBDIRS variable conditionally if,
as in the case of GNU Inetutils, you want to only build a subset of
the entire package.
To illustrate how this works, let’s assume we have two directories
src/ and opt/. src/ should always be built, but we
want to decide in
configure whether opt/ will be built
or not. (For this example we will assume that opt/ should be
built when the variable ‘$want_opt’ was set to ‘yes’.)
make should thus always recurse into src/, and
only conditionally into opt/.
However ‘make dist’ should always recurse into both src/
and opt/ unconditionally, because opt/ should be distributed even
if it is not needed in the current configuration, so
opt/Makefile needs to be created.
The main way to manage conditionally built subdirectories is to always
configure in all subdirectories. This is achieved with the
variable. Alternatively, it may be possible not to configure a subdirectory
you need to distribute: see Unconfigured Subdirectories, below.
|• Subdirectories with AM_CONDITIONAL|
|• Subdirectories with AC_SUBST|
|• Unconfigured Subdirectories|