Trouble building a Cross Compiler to use to build a x86_64 kernel.

nLEyETn · 03-11-2007, 03:38 AM

I'm attempting to build a Cross Compiler and keep running into problems; so if anyone can please help me it would be much appreciated. I'm using a Slackware 11.0 host system with a 2.6.20.1 kernel with the default ARCH="i386" built by myself. I then downloaded 'binutils-2.17,' 'gcc-4.1.2' and 'glibc-2.5.' I then built binutils with the following sequence:

Code:

unset CFLAGS
unset CXXFLAGS
../binutils/binutils-2.17/configure  --prefix=/usr/local/env64 --target=x86_64-sw-linux --with-lib-path=/usr/local/tmp/lib --enable-shared --enable-64-bit-bfd --disable-multilib
make
make install

This seemed to work fine. I should mention that /usr/local/tmp and it's subdirectory lib are empty. I then built gcc as so:

Code:

export PATH=$PATH:/usr/local/env64
export CFLAGS='-Dinhibit_libc'
../gcc/gcc-4.1.2/configure   --prefix=/usr/local/env64 --target=x86_64-sw-linux --with-local-prefix=/usr/local/tmp --disable-shared --disable-multilib --disable-threads --enable-languages=c
make all-gcc
make install-gcc

This also seemed to build without any real problems. Then I tried to build glibc like so:

Code:

mkdir /usr/local/env64/x86_64-sw-linux/include
cp -r /usr/src/linux/include/linux /usr/local/env64/x86_64-sw-linux/include
cp -r /usr/src/linux/include/asm-generic /usr/local/env64/x86_64-sw-linux/include
cp -r /usr/src/linux/include/asm-x86_64 /usr/local/env64/x86_64-sw-linux/include/asm
BUILD_CC="gcc" CC="x86_64-sw-linux-gcc -m64" AR="x86_64-sw-linux-ar" RANLIB="x86_64-sw-linux-ranlib" ../glibc/glibc-2.5/configure --prefix=/usr/local/env64 --host=x86_64-sw-linux --build=i686-pc-linux-gnu --disable-profile --enable-add-ons --with-tls --enable-kernel=2.6.0 --with-binutils=/usr/local/env64/bin --with-headers=/usr/local/env64/x86_64-sw-linux/include

This gives me the following error:

"configure: error: forced unwind support is required." I have no idea what to do now, so if anyone can please help I'd appreciate it.

Mahonri · 05-07-2007, 06:51 AM

I've scoured the net trying to figure out how to overcome this. I'm trying to build a x86-64 -> i686 cross compiler. From what I can tell, the problem has something to do with a dependency on a libc. In other words, you need a libc to compile a libc!

Were you ever able to solve this problem?

nLEyETn · 05-08-2007, 06:35 PM

Sorry, no. I ended up installing Slamd64 in my case instead of using Slackware. Later on I decided to skip the headaches for now, and just go with Slackware. Slamd64 was nice but you really need a dual environment with 32 and 64 bits since there are some binaries which I cannot recompile because they are closed source. Such as video codecs. Basically I head to compile alot of stuff for both 32 and 64 bits, but that got tedious, so I decided to go with a strict 32 environment for now since everything is supported on that.