i686 Multilib Question

i686 Multilib Question

[Armin K.]

Hi there, this is my first post on gcc mailing lists.

I have currently i686 system (Linux From Scratch) and I would like to 
bootstrap multilib compiler on that one. The problem is, I don't have 
any working multilib compiler, only i686 one. And I don't know where to 
start.

I have tried first enabling multilib and all targets in binutils, then 
statically compiling gcc.

I ran into problems in bootstrap stage and tought it was a bug. A more 
detailed report about this can be found in bug report 
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53662

Has anyone managed to bootstrap multilib compiler using i686 one? I 
would like to have i686 compiler, but also I want to be able to use -m64 
which is done by multilib right? I am aware that I need multilib 
binutils, static gcc to compile multilib glibc and use it to bootstrap 
full gcc with shared libraries and such. Am I right? But I am unable to 
accomplish that. Could anyone guide me in right direction? Google does 
not help very much. And yes, I want this. I don't want to install or 
build 64 bit operating system.

Regards.

Re: i686 Multilib Question

[Ian Lance Taylor]

"Armin K." <krejzi@email.com> writes:

> I have currently i686 system (Linux From Scratch) and I would like to
> bootstrap multilib compiler on that one. The problem is, I don't have
> any working multilib compiler, only i686 one. And I don't know where
> to start.
>
> I have tried first enabling multilib and all targets in binutils, then
> statically compiling gcc.
>
> I ran into problems in bootstrap stage and tought it was a bug. A more
> detailed report about this can be found in bug report
> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53662
>
> Has anyone managed to bootstrap multilib compiler using i686 one? I
> would like to have i686 compiler, but also I want to be able to use
> -m64 which is done by multilib right? I am aware that I need multilib
> binutils, static gcc to compile multilib glibc and use it to bootstrap
> full gcc with shared libraries and such. Am I right? But I am unable
> to accomplish that. Could anyone guide me in right direction? Google
> does not help very much. And yes, I want this. I don't want to install
> or build 64 bit operating system.

In order to build a GCC that can build 64-bit binaries, you need to have
a 64-bit C library and 64-bit binutils installed.  Do you?

There is a shell script config.guess in the top level GCC directory.
When you run it, does it print x86_64-unknown-linux-gnu or
i686-unknown-linux-gnu?  If it prints i686, that suggests that uname -m
on your system prints i686, and that suggests that your kernel is not
running in 64-bit mode.

Ian

Re: i686 Multilib Question

[Armin K.]

On 06/15/2012 12:03 AM, Ian Lance Taylor wrote:
> "Armin K."<krejzi@email.com>  writes:
>
>> Alright, I have built x86_64 cross compiler, built 64bit glibc with
>> which sort of works. I have built static i686 compiler with multilib
>> support (i686-linux-gnu-gcc/gcc -m64 works with that one), but now I
>> am trying to build shared set of compilers including c, c++ and ada
>> one (I have built static gnat stuff with static gcc), but I still keep
>> failing with same error as in the bug report, ie - no x86_64
>> support. Looking at config.log it seems to be using xgcc from stage1
>> bootstrap which isn't multilib capable for some reason. So, what am I
>> still doing wrong? I want i686 compiler, but I also want it to be able
>> to use -m64 with it.
>
>
> Sorry I missed saying this last time: please reply to gcc-help, not
> just to me.  Thanks.
>
> Did you configure with --enable-targets=all ?
>
> Ian

Whoops, sorry. I just hit reply and didn't pay attention to e mail 
address which was sent to.

Yes, I configured static gcc with --enable-targets=all and even dynamic.

$ /usr/gcc/bin/gcc -v
Using built-in specs.
COLLECT_GCC=/usr/gcc/bin/gcc
COLLECT_LTO_WRAPPER=/usr/gcc/lib/gcc/i686-linux-gnu/4.6.3/lto-wrapper
Target: i686-linux-gnu
Configured with: ../src/configure --prefix=/usr/gcc 
--libdir=/usr/gcc/lib --libexecdir=/usr/gcc/lib --without-headers 
--with-newlib --disable-shared --disable-nls --disable-decimal-float 
--disable-libgomp --disable-libmudflap --disable-libquadmath 
--disable-libssp --disable-threads --without-ppl --without-cloog 
--enable-targets=all --with-mpfr-include=/home/armin/src/src/mpfr/src 
--with-mpfr-lib=/home/armin/src/build/mpfr/.libs --enable-multilib 
--enable-bootstrap --enable-languages=c,ada --host=i686-linux-gnu 
--build=i686-linux-gnu --target=i686-linux-gnu
Thread model: single
gcc version 4.6.3 (GCC)