Re: vpath builds and include paths

[Guido Draheim]

Bob Friesenhahn wrote:
> On Mon, 22 Dec 2003 address@hidden wrote:
>
>
> > However, if I want to build in a separate build tree (relying on
> > VPATH), then I try the following:
> >
> > mkdir /build
> > cd /build
> > /test/configure
> > make
> >
> > This attempts to build in this new /build directory, but during
> > compilation it cannot locate the header file, myproj.hpp, and the rest
> > of the build fails.  What do I need to do in order to tell automake
> > where this header is?  I've already tried using the absolute path
> > variables in the Makefile.am:
> >
> > INCLUDE = -I$(abs_top_srcdir)/project2/sublevel/inc
>
>
> Note that abs_top_srcdir calculation was broken in Autoconf 2.58.  It
> is fixed in 2.59.
>
> Rather than using INCLUDE you should use AM_CPPFLAGS.  For example
>
> AM_CPPFLAGS = -I$(top_srcdir)/project2/sublevel/inc

*g* or override DEFS to let the local includes be found first always...
since the days I have had serious problems with includes I do tend
to make up projects only ever with a prefix/my.h which needs then only
-I$(top_srcdir) where top_srcdir/prefix/ exists. That needs to override
the default_includes as well to cut away the -I. -I$(srcdir) settings.
Personally, I'd never do myproj.h anymore, only ever now myproj/inc.h

just my 2cent,
-- guido                                http://AC-Archive.sf.net
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