Re: using mkoctfile with autotools

[Mike Miller]

On Fri, Jan 18, 2013 at 9:53 AM, c. wrote:
> Hi,
>
> I am building a standalone program that links to Octave and I'm trying to use
> mkoctfile in an autoconf test to determine appropriate include and link flags,
> for example:
>
> AC_SUBST(OCTAVE_CPP_FLAGS, "$(mkoctfile -p CPPFLAGS)")
>
> the problem is that if a value is given for CPPFLAGS, in an environment 
> variable
> or on the configure command line, e.g.
>
> ./configure CPPFLAGS=-I/my_includes_dir
>
> then "mkoctfile -p CPPFLAGS" will return "/my_includes_dir" rather than the 
> the
> preprocessor flags needed to include Octave, and similar problems occur with 
> other
> variable like CXXFLAGS or CXXPICFLAG and so on …
>
> Is this behaviour of mkoctfile intended? Is there any way I can work around 
> it?

Looks intended inasmuch as it treats all variables the same way, and I
think most Forge packages use the environment to override at least
CFLAGS and LFLAGS.

To work around, both of the following work for me:

$(env -i PATH=$PATH mkoctfile -p CPPFLAGS)

$(unset CPPFLAGS; mkoctfile -p CPPFLAGS)

HTH
--
mike