Re: [PATCH] add CC_STATIC_LIBSTDCXX option for gcc-4.4 and newer

["Yann E. MORIN" <yann dot morin dot 1998 at anciens dot enib dot fr>]

Johannes, All,

On Thursday 29 July 2010 17:26:39 Johannes Stezenbach wrote:
> add CC_STATIC_LIBSTDCXX option for gcc-4.4 and newer

There had already been some trials at that, and I was not very happy
with the outcome. That one I like much better because we can then
have config knobs 'select' that if needed.

Eventually, I'd like that we push the idea a bit further. It seems
that on some hosts (eg. cygwin or mingw32), we always need to link
with libstdc++ statically (or at least it is an easy workaround).

But that will have to wait post-1.8.0.

> Idea and know-how taken from CodeSourcery build script.
> 
> Normal build:
>   $ ldd arm-unknown-linux-uclibcgnueabi-gcc 
> 	linux-gate.so.1 =>  (0xb77f3000)
> 	libstdc++.so.6 => /usr/lib/libstdc++.so.6 (0xb76e8000)
> 	libc.so.6 => /lib/i686/cmov/libc.so.6 (0xb75a1000)
> 	libm.so.6 => /lib/i686/cmov/libm.so.6 (0xb757a000)
> 	/lib/ld-linux.so.2 (0xb77f4000)
> 	libgcc_s.so.1 => /lib/libgcc_s.so.1 (0xb755c000)
> 
> CC_STATIC_LIBSTDCXX=y:
>   $ ldd arm-unknown-linux-uclibcgnueabi-gcc 
> 	linux-gate.so.1 =>  (0xb7843000)
> 	libc.so.6 => /lib/i686/cmov/libc.so.6 (0xb76e6000)
> 	/lib/ld-linux.so.2 (0xb7844000)
> 
> I made CC_STATIC_LIBSTDCXX default=y since I think
> it is always desirable.
> 
> Signed-off-by: Johannes Stezenbach <js@sig21.net>
> 
> diff -r 8ed7bda0e44d config/cc/gcc.in
> --- a/config/cc/gcc.in	Thu Jul 29 14:38:58 2010 +0200
> +++ b/config/cc/gcc.in	Thu Jul 29 16:44:29 2010 +0200
> @@ -183,6 +183,18 @@
>      default "4.0.4" if CC_V_4_0_4
>      default "3.4.6" if CC_V_3_4_6
>  
> +config CC_STATIC_LIBSTDCXX
> +    bool
> +    prompt "link libstdc++ statically into the gcc binary"
> +    default y
> +    depends on CC_GCC_4_4_or_later
> +    help
> +      Newer gcc versions use the PPL library which is C++ code.  Statically
> +      linking libstdc++ increases the likeliness that the gcc binary will
> +      run on machines other than the one which it was built on, without
> +      having to worry about distributing the matching version of libstdc++
> +      along with it.
> +
>  config CC_CXA_ATEXIT
>      bool
>      prompt "Use __cxa_atexit"
> diff -r 8ed7bda0e44d scripts/build/cc/gcc.sh
> --- a/scripts/build/cc/gcc.sh	Thu Jul 29 14:38:58 2010 +0200
> +++ b/scripts/build/cc/gcc.sh	Thu Jul 29 16:44:29 2010 +0200
> @@ -338,10 +338,16 @@
>          extra_config+=("--enable-cxx-flags=${CC_ENABLE_CXX_FLAGS}")
>      fi
>  
> -    # When companion libraries are build static (eg !shared),
> -    # the libstdc++ is not pulled automatically, although it
> -    # is needed. Shoe-horn it in our LDFLAGS
> -    if [ "${CT_COMPLIBS_SHARED}" != "y" ]; then
> +    if [ "${CT_CC_STATIC_LIBSTDCXX}" = "y" ]; then
> +        # this is from CodeSourcery arm-2010q1-202-arm-none-linux-gnueabi.src.tar.bz2
> +        # build script
> +        # FIXME: if the host gcc is gcc-4.5 then presumably we could use -static-libstdc++,
> +        # see http://gcc.gnu.org/ml/gcc-patches/2009-06/msg01635.html

Yes. Post-1.8.0.

> +        extra_config+=("--with-host-libstdcxx=-static-libgcc -Wl,-Bstatic,-lstdc++,-Bdynamic -lm")
> +    elif [ "${CT_COMPLIBS_SHARED}" != "y" ]; then
> +        # When companion libraries are build static (eg !shared),
> +        # the libstdc++ is not pulled automatically, although it
> +        # is needed. Shoe-horn it in our LDFLAGS
>          final_LDFLAGS='-lstdc++'
>      fi
>      if [ "${CT_CC_GCC_USE_GMP_MPFR}" = "y" ]; then

Queued for 1.8.0! :-)

Regards,
Yann E. MORIN.

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