#!/bin/env bash

pacman --noconfirm -Syu

mkdir toolchain && cd toolchain

# Install runtime dependencies

pacman --noconfirm --needed -S \
  base-devel \
  libelf \
  libmpc \
  zlib

# Install build dependencies

pacman --noconfirm --needed --asdeps -S \
  gmp \
  mpfr

# Download sources

curl -LO https://ftp.gnu.org/gnu/binutils/binutils-$BINUTILS_VERSION.tar.xz
curl -LO https://ftp.gnu.org/gnu/gcc/gcc-$GCC_VERSION/gcc-$GCC_VERSION.tar.xz
curl -LO ftp://sourceware.org/pub/newlib/newlib-$NEWLIB_VERSION.tar.gz

# Build binutils

mkdir binutils && cd binutils && mkdir .build

tar xf ../binutils-$BINUTILS_VERSION.tar.xz

cd .build

../binutils-$BINUTILS_VERSION/configure \
  --target=$TARGET \
  --prefix=/usr/lib/$TARGET \
  --bindir=/usr/bin \
  --libdir=/usr/lib/$TARGET \
  --disable-nls \
  --disable-werror

make -j$(nproc)

make install

cd /toolchain

# Build first iteration of GCC (for newlib boostrapping)

mkdir gcc-bootstrap && cd gcc-bootstrap && mkdir .build

tar xf ../gcc-$GCC_VERSION.tar.xz

cd gcc-$GCC_VERSION

cat <<EOF > gcc/config/i386/t-x86_64-elf
MULTILIB_OPTIONS += mno-red-zone
MULTILIB_DIRNAMES += no-red-zone
EOF

patch -p0 -i /patches/gcc-$GCC_VERSION-$TARGET.patch

cd ../.build

CFLAGS=${CFLAGS/-Werror=format-security/}
CXXFLAGS=${CXXFLAGS/-Werror=format-security/}

../gcc-$GCC_VERSION/configure \
  --target=$TARGET \
  --prefix=/usr \
  --disable-nls \
  --disable-plugin \
  --libexecdir=/usr/lib \
  --enable-languages=c,c++ \
  --without-headers

make -j$(nproc) all-gcc
make -j$(nproc) all-target-libgcc
make install-gcc
make install-target-libgcc

cd /toolchain

# Build newlib

mkdir newlib && cd newlib && mkdir .build

tar xf ../newlib-$NEWLIB_VERSION.tar.gz

cd .build

LDFLAGS=-mno-red-zone ../newlib-$NEWLIB_VERSION/configure \
  --target=$TARGET \
  --prefix=/usr \
  --disable-newlib-supplied-syscalls \
  --disable-newlib-fseek-optimization \
  --disable-newlib-io-float \
  --disable-nls \
  --disable-werror

make -j$(nproc)
make install

cd /toolchain

# Build final gcc

mkdir gcc-final && cd gcc-final && mkdir .build

tar xf ../gcc-$GCC_VERSION.tar.xz

cd gcc-$GCC_VERSION

cat <<EOF > gcc/config/i386/t-x86_64-elf
MULTILIB_OPTIONS += mno-red-zone
MULTILIB_DIRNAMES += no-red-zone
EOF

patch -p0 -i /patches/gcc-$GCC_VERSION-$TARGET.patch

cd ../.build

CFLAGS=${CFLAGS/-Werror=format-security/}
CXXFLAGS=${CXXFLAGS/-Werror=format-security/}


../gcc-$GCC_VERSION/configure \
  CFLAGS_FOR_TARGET='-mcmodel=large' \
  --target=$TARGET \
  --prefix=/usr \
  --disable-nls \
  --disable-plugin \
  --libexecdir=/usr/lib \
  --enable-languages=c,c++ \
  --enable-cxx-flags=-fno-exceptions \
  --disable-hosted-libstdcxx \
  --disable-wchar_t \
  --with-newlib

make -j$(nproc) all-gcc
make -j$(nproc) all-target-libgcc
make -j$(nproc) all-target-libstdc++-v3
make install-gcc
make install-target-libgcc
make install-target-libstdc++-v3

cd /

rm -rf toolchain