This is the mail archive of the
libstdc++@gcc.gnu.org
mailing list for the libstdc++ project.
RE: cross libstdc++-v3 configuration
- From: Matthew Jones <matthewjones at vw1600e dot org dot uk>
- To: bkoz at redhat dot com, libstdc++ at gcc dot gnu dot org
- Cc: crossgcc at sources dot redhat dot com
- Date: Thu, 17 Feb 2005 16:35:08 +0000
- Subject: RE: cross libstdc++-v3 configuration
> > I'm trying to build libstdc++-v3 for a cross development system.
>
> How, exactly?
$ /cygdrive/c/gnu/gcc-3.4.3/libstdc++-v3/configure <blah blah>
> How did you arrange your sources?
In the normal way for running crosstool script:
The gcc 3.4.3 tar is expanded here: /cygdrive/c/gnu/gcc-3.4.3
> How did you configure?
I have tried all sorts of combinations of parameters for configure.
> Did you try reading the docs first?
Yes, they aren't helping, as I mentioned:
> > Even after reading libstdc++-v3/configure --help,
> > it is not clear to me what I need to set.
> > Host is i686-pc-cygwin, target system is powerpc-ibm-eabi.
>
> All you should have to do is specify --target=powerpc-eabisim.
That didn't work, I'm afraid.
> Please, crosstools mail should just be posted on the crosstool list.
This is an issue with building libstdc++-v3 for a cross target, not especially a
crosstool problem. I have cross-posted but nobody on crossgcc is answering.
I have been poring over libstdc++-v3/configure and found this gem:
# You will slowly go insane if you do not grok the following fact: when
# building v3 as part of the compiler, the top-level /target/ becomes the
# library's /host/. configure then causes --target to default to --host,
# exactly like any other package using autoconf. Therefore, 'target' and
# 'host' will always be the same. This makes sense both for native and
# cross compilers, just think about it for a little while. :-)
#
# Also, if v3 is being configured as part of a cross compiler, the top-level
# configure script will pass the "real" host as $with_cross_host.
This helped enormously. I have been slowly going insane.
Another thing I found was that libstdc++-v3/configure seems to ignore --prefix
when looking for the compiler etc. It just looks in the path, and therefore
gets gcc from /usr/bin. This is usually the native compiler. When I copied the
cross compliler there it got further but gave me the good old "No support for
this host/target combination".
I am now pursuing the cause of this error in the hope that I can patch the
configure script to make it work.
--
Matthew JONES
http://www.tandbergtv.com/