libstdc++.so depends on libstdc++.so

[Andrew Haley]

tp@fonz.de wrote:
> Hi,
> 
> I'm cross-compiling gcc (with c++ enabled) to run on an arm target.
> Overall it works well, except:
> 
> $ arm-unknown-linux-uclibc-readelf -d libstdc++.so.6.0.8
> ...
>  0x00000001 (NEEDED)                     Shared library: [libstdc++.so.6]
>  0x0000000e (SONAME)                     Library soname: [libstdc++.so.6]
>  0x0000000f (RPATH)                      Library rpath: [/home/.../arm-unknown-linux-uclibc/lib]
> 
> The resulting libstdc++ depends on libstdc++ and has an rpath into the
> cross-tools directory. I've had the same with a glibc-based toolchain
> and with gcc 3.4, 4.1 and 4.2.

That doesn't happen to me: I get

 $ ./bin/arm-linux-gnueabi-readelf -d ./arm-linux-gnueabi/lib/libstdc++.so.6.0.10 

Dynamic section at offset 0xc5ef4 contains 29 entries:
  Tag        Type                         Name/Value
 0x00000001 (NEEDED)                     Shared library: [libm.so.6]
 0x00000001 (NEEDED)                     Shared library: [libc.so.6]
 0x00000001 (NEEDED)                     Shared library: [libgcc_s.so.1]
 0x0000000e (SONAME)                     Library soname: [libstdc++.so.6]

I'd like to know exactly how this was configured and built.

> Comments in the configure scripts and Makefiles indicate that
> libstdc++ is not to be linked with target-g++, because that includes
> -lstdc++. But it's exactly doing that. I haven't found a way to make
> it do the right thing, except dirty sed'ding various libtool and
> configure scripts. 
> 
> Another annoyance appears when libiconv is installed in the target
> sysroot. If gcc's configure detects iconv.h there, the
> target-sysroot/include path ends up in CPPFLAGS in gcc/Makefile, which
> in turn is used to build gcc/build/gen* - which of course fails
> (mixing glibc host headers and uclibc target headers). None of
> --without-iconv-prefix, --with-iconv-prefix=/target-sysroot or
> --with-iconv-prefix=/usr helped. Sed'ding gcc/Makefile (remove
> CPPFLAGS from BUILD_CFLAGS) helps.

This doesn't happen to me either.  I have iconv.h in my sysroot too.

Here's what I did:

  $ /home/aph/gcc/trunk/configure --prefix=/local/x-arm-gcc/install --with-build-sysroot=/local/x-arm-gcc/rootfs-f8 --disable-libssp --disable-libgomp --disable-libmudflap --enable-libgcj --disable-bootstrap --disable-multilib --disable-static --disable-sjlj-exceptions --target=arm-linux-gnueabi --enable-languages=c,c++,java

Andrew.