Initial commit - Begun rewrite of website generator

pages/2012-06-13-Cross-Compiler.md

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+layout: post
+title: "Cross compiler"
+subtitle: "Setting up under OSX Lion"
+tags: [osdev]
+
+For simplicity, I chose to set up a so-called cross compiler for osdeving.  In
+OSX Lion, this is what I did.
+
+First of all, I installed Xcode from the Mac App store.  Since version 4.3,
+Xcode doesn't install any command line tools anymore, so this had to be done
+manually:
+
+- Open Xcode
+- Go the Preferences
+- Choose Downloads
+- Find Command Line Tools and click Install.
+
+This is better than some earlier versions, though, which use a buggy
+c-compiler. An update was required on one of my computers.
+
+Compiling gcc also requires the mpfr package to be installed. This I did with
+[Homebrew](http://mxcl.github.com/homebrew/).
+
+	brew install mpfr
+{: .prettyprint}
+
+I downloaded all the sources I needed from [gnu.org](http://gnu.org).
+
+	curl -O http://ftp.gnu.org/gnu/binutils/binutils-2.22.tar.gz
+	curl -O http://ftp.gnu.org/gnu/gcc/gcc-4.6.3/gcc-core-4.6.3.tar.gz
+	
+	curl -O http://ftp.gnu.org/gnu/gmp/gmp-5.0.2.tar.gz
+	curl -O http://ftp.gnu.org/gnu/mpfr/mpfr-3.1.0.tar.gz
+	curl -O http://www.multiprecision.org/mpc/download/mpc-0.9.tar.gz
+{: .prettyprint .lang-bash}
+
+Feel free to use later versions, but if you do, I cannot guarantee that the
+code posted in my logs will work for you (it's very likely to work, but not
+*guaranteed*).  Gmp, mpfr and mpc are floating point libraries that are used by
+gcc, so after extracting all archives, they are simply copied into the gcc
+source
+
+	mv gmp-5.0.2 gcc-4.6.3/gmp
+	mv mpfr-3.1.0 gcc-4.6.3/mpfr
+	mv mpc-0.9 gcc-4.6.3/mpc
+{: .prettyprint .lang-sh}
+
+In order not to mess up the source, binutils and gcc were built out of tree.
+
+	mkdir build-binutils
+	cd build-binutils
+	
+	export PREFIX=/usr/local/cross
+	export TARGET=i386-elf
+	../binutils-2.22/configure --target=$TARGET --prefix=$PREFIX --disable-nls
+	make all
+	make install
+{: .prettyprint .lang-bash}
+
+And the same for gcc, using the new binutils
+
+	cd ..
+	mkdir build-gcc
+	cd build-gcc
+	export PATH=$PATH:$PREFIX/bin
+	../gcc-4.6.3/configure --target=$TARGET --prefix=$PREFIX --disable-nls --enable-languages=c --without-headers
+	make all-gcc
+	make install-gcc
+{: .prettyprint .lang-bash}
+
+It's really important to run _make all-gcc_ and _make install-gcc_ and __not__
+_make all_ and _make install_ here. It probably works anyway - if you ever
+manage to get it to actually compile...
+
+And that's it!