cfenollosa_os-tutorial/24-el-capitan

Goal: Update our build system to El Capitan

If you were following this guide from the beginning and upgraded to El Capitan only to find that Makefiles don't compile anymore, follow these instructions to upgrade your cross-compiler.

Otherwise, move on to the next lesson

Upgrading the cross-compiler

We will follow the same instructions as in lesson 11, more or less.

First, run brew upgrade and you will get your gcc upgraded to version 5.0 (at the time this guide was written)

Then run xcode-select --install to update OSX commandline tools

Once installed, find where your packaged gcc is (remember, not clang) and export it. For example:

export CC=/usr/local/bin/gcc-5
export LD=/usr/local/bin/gcc-5

We will need to recompile binutils and our cross-compiled gcc. Export the targets and prefix:

export PREFIX="/usr/local/i386elfgcc"
export TARGET=i386-elf
export PATH="$PREFIX/bin:$PATH"

binutils

Remember: always be careful before pasting walls of text from the internet. I recommend copying line by line.

mkdir /tmp/src
cd /tmp/src
curl -O http://ftp.gnu.org/gnu/binutils/binutils-2.24.tar.gz # If the link 404's, look for a more recent version
tar xf binutils-2.24.tar.gz
mkdir binutils-build
cd binutils-build
../binutils-2.24/configure --target=$TARGET --enable-interwork --enable-multilib --disable-nls --disable-werror --prefix=$PREFIX 2>&1 | tee configure.log
make all install 2>&1 | tee make.log

gcc

cd /tmp/src
curl -O http://mirror.bbln.org/gcc/releases/gcc-4.9.1/gcc-4.9.1.tar.bz2
tar xf gcc-4.9.1.tar.bz2
mkdir gcc-build
cd gcc-build
../gcc-4.9.1/configure --target=$TARGET --prefix="$PREFIX" --disable-nls --disable-libssp --enable-languages=c --without-headers
make all-gcc 
make all-target-libgcc 
make install-gcc 
make install-target-libgcc 

Now try to type make on this lesson's folder and check that everything compiles smoothly