Occasionally it is useful to know which Makefile variables Automake uses for compilations; for instance, you might need to do your own compilation in some special cases.
Some variables are inherited from Autoconf; these are CC
,
CFLAGS
, CPPFLAGS
, DEFS
, LDFLAGS
, and
LIBS
.
There are some additional variables that Automake defines on its own:
AM_CPPFLAGS
Automake already provides some -I options automatically. In
particular it generates -I$(srcdir), -I., and a
-I pointing to the directory holding config.h (if
you've used AC_CONFIG_HEADERS
or AM_CONFIG_HEADER
). You
can disable the default -I options using the
nostdinc option.
AM_CPPFLAGS
is ignored in preference to a per-executable (or
per-library) _CPPFLAGS
variable if it is defined.
INCLUDES
AM_CPPFLAGS
(or any per-target
_CPPFLAGS
variable if it is used). It is an older name for the
same functionality. This variable is deprecated; we suggest using
AM_CPPFLAGS
and per-target _CPPFLAGS
instead.
AM_CFLAGS
_CFLAGS
.
COMPILE
AM_LDFLAGS
_LDFLAGS
.
LINK
CFLAGS
); it takes as “arguments” the names of the object files
and libraries to link in.