Re: libraries are not supported on this platform

[Simon Wright <simon@pushface.org>]

Vincent Aurele <vaurele@gmx.com> writes:

> I have a cross-compiler (target: arm-none-eabi) and I'm trying to
> compile my project with it. This project use a precompiled (static) C
> library so I have defined a 'library project' in lib.gpr with 'for
> Externally_Built use "True";'. Using my standard gnatmake, it works
> fine but when I try to compile my project with the cross-compiler, I
> have an error:
>
> lib.gpr:8:24: warning: libraries are not supported on this platform
>
> and my lib is not used by the linker (so the link fails)
>
> I understand that my target don't support dynamic library but static
> library are perfectly fine, so I think it should be work.  Is this an
> issue with my cross-compiler? Is there a way to make it work?

Poking around in GNAT GPL 2012, in {prefix}/share/gprconfig/linker.xml
there's an interesting section at line 326

  <!--  Systems with no support for shared libraries, but with static libraries -->
  <configuration>
    <targets>
       <target name="^.*aix.*$" />
       <target name="^.*lynxos.*$" />
       <target name="^powerpc-elf$" />
       <target name="^powerpc-eabispe$" />
       <target name="^erc32-elf$" />
       <target name="^leon-elf$" />
       <target name="^leon3-elf$" />
       <target name="^.*wrs-vxworks.*$" />
       <target name="^avr$" />
    </targets>
    <config>
   for Library_Support  use "static_only";
   for Library_Builder  use "${GPRCONFIG_PREFIX}libexec/gprbuild/gprlib";
    </config>
  </configuration>

and I think that the version of this file your cross-gnatmake (or
gprbuild) is using has instead, in the part that matches arm-none-eabi,

   for Library_Support  use "none";

You'll need to work out how teach it to use the correct cross-ar etc as
well.

There's the GPRBuild manual[1], and the section on GPRconfig may be
useful.

[1] http://docs.adacore.com/gprbuild-docs/html/gprbuild_ug.html