Re: Automatic dependecy based compilation targets

[Ralf Wildenhues]

Hello Mihai, 

* Dizzy wrote on Fri, Feb 02, 2007 at 11:49:10AM CET:
> On Thursday 01 February 2007 19:40, Ralf Wildenhues wrote:
> >
> > If you want your libfoo and libbar to not be convenience archives, but
> > installable libraries, then for the EXTRA* stuff I think you need to put
> > "-rpath $(libdir)" yourself in libfoo_la_LDFLAGS etc. 
>
> I don't want libfoo/libbar to be installable libraries, I want them to be 
> convenience libraries that should be build only if at make time there is a 
> dependency on them (thus they are EXTRA but I cannot use 
> EXTRA_noinst_LTLIBRARIES because it says some error about some noinstdir 
> variable not declared). And I also want to have installable libraries be made 
> by incorporating code form libfoo/libbar convenience libraries. 

Ah, yes.  This is where your questions are answered:
<http://sources.redhat.com/automake/automake.html#Conditional-Libtool-Librar 
ies> 

Something like this should work: 

Makefile.am:
noinst_LTLIBRARIES = liba1.la @SUB1@
lib_LTLIBRARIES = libb1.la @SUB2@
EXTRA_LTLIBRARIES = liba2.la libb2.la
libb2_la_LDFLAGS = -rpath $(libdir) 

configure.ac:
# ...
AC_SUBST([SUB1], [liba2.la])
AC_SUBST([SUB2], [libb2.la]) 

and so on. 

> And then I want to link some installable executables (sbin_PROGRAMS) and 
> installable libraries (lib_LTLIBRARIES) with a set of those convenience 
> libraries (I know what dependency a final target like an installable 
> executable/library has and I express those dependencies listing as 
> LDADD/LIBADD the convenience libraries I know they directly need but 
> sometimes those convenience libraries themselves had a dependency on some 
> listed convenience libraries and this creates problems for lib_LTLIBRARIES 
> when eventually it gets to link duplicate convenience libraries). Now what I 
> noticed is that while there are no problems with linking duplicate 
> convenience libraries into executables, there are problems (those multiple 
> definitions linking errors) linking duplicate convenience libraries into an 
> installable library.

Well.  Neither is completely 100% portable; IIRC not even linking a
convenience library into a program is (but that is a Libtool limitation
that could be overcome, AFAIK).  I don't see a way around you making
sure you only incorporate each convenience library into an output at
most once. 

Hope that helps. 

Cheers,
Ralf