Change to gcc-multilib

Dockerfile

@@ -3,7 +3,7 @@ MAINTAINER justin@dray.be
 
 RUN mkdir -p /build
 WORKDIR /build
-RUN pacman -Syuq --noconfirm --needed base-devel && rm -rf /var/cache/pacman/pkg/*
+RUN pacman -Syuq --noconfirm --needed $(pacman -Sgq base-devel | grep -v gcc) gcc-multilib && rm -rf /var/cache/pacman/pkg/*
 RUN pacman -Syuq --noconfirm --needed git mercurial bzr subversion openssh && rm -rf /var/cache/pacman/pkg/*
 RUN useradd -d /build build-user
 ADD sudoers /etc/sudoers