Last one for today: recommendations on proper style/form

There are two things I am not quite clear on from the autoconf and automake
documentation, and hoped to get some pointers on what is considered ?best
practice?:

(1) If I have flags that I do not want overridden by users when configure is
executed, it seems like the recommendation is to place those flags in
variables such as AM_CFLAGS and AM_LDFLAGS. But what wasn't clear was
whether or not it was kosher, or recommended, or bad practice to set the
values of these in configure.ac as a result of some tests and then
AC_SUBST([...]) those variables at the end of configure.ac so that they are
written to the Makefile. What is the current recommended practice?

(2) If I want to add includes (e.g., "-I/path/to/include" to only certain
modules within my build tree where they apply, how do I go about it? My
concern is that thinks like foo_CPPFLAGS overrides the CPPFLAGS setting, and
I want to add the includes, not override the defaults.

Thanks in advance,
Greg

--
J. Gregory Wright <gwright@xxxxxxxxxxxxxxxxxx>
 
Integrity Applications Incorporated <http://www.integrity-apps.com>
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