mirror of
https://github.com/cfenollosa/os-tutorial.git
synced 2024-10-27 20:34:19 +00:00
77 lines
2.5 KiB
Markdown
77 lines
2.5 KiB
Markdown
*Concepts you may want to Google beforehand: cross-compiler*
|
|
|
|
**Goal: Create a development environment to build your kernel**
|
|
|
|
If you're using a Mac, you will need to do this process right away. Otherwise, it could have waited
|
|
for a few more lessons. Anyway, you will need a cross-compiler once we jump to developing in a higher
|
|
language, that is, C. [Read why](http://wiki.osdev.org/Why_do_I_need_a_Cross_Compiler%3F)
|
|
|
|
I'll be adapting the instructions [at the OSDev wiki](http://wiki.osdev.org/GCC_Cross-Compiler).
|
|
|
|
|
|
Required packages
|
|
-----------------
|
|
|
|
First, install the required packages. On linux, use your package distribution. On a Mac, [install brew](http://brew.sh/) if
|
|
you didn't do it on lesson 00, and get those packages with `brew install`
|
|
|
|
- gmp
|
|
- mpfr
|
|
- libmpc
|
|
- gcc
|
|
|
|
Yes, we will need `gcc` to build our cross-compiled `gcc`, especially on a Mac where gcc has been deprecated for `clang`
|
|
|
|
Once installed, find where your packaged gcc is (remember, not clang) and export it. For example:
|
|
|
|
```
|
|
export CC=/usr/local/bin/gcc-4.9
|
|
export LD=/usr/local/bin/gcc-4.9
|
|
```
|
|
|
|
We will need to build binutils and a cross-compiled gcc, and we will put them into `/usr/local/i386elfgcc`, so
|
|
let's export some paths now. Feel free to change them to your liking.
|
|
|
|
```
|
|
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.
|
|
|
|
```sh
|
|
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
|
|
---
|
|
```sh
|
|
cd /tmp/src
|
|
curl -O https://ftp.gnu.org/gnu/gcc/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
|
|
```
|
|
|
|
That's it! You should have all the GNU binutils and the compiler at `/usr/local/i386elfgcc/bin`, prefixed by `i386-elf-` to avoid
|
|
collisions with your system's compiler and binutils.
|
|
|
|
You may want to add the `$PATH` to your `.bashrc`. From now on, on this tutorial, we will explicitly use the prefixes when using
|
|
the cross-compiled gcc.
|