Installed gcc-multilib conflicts with gcc-5-arm-linux-gnueabihf when using --target-arch

[Cris Dywan]

$ snapcraft --target-arch=armhf pull
[...]
Installing build dependencies: binutils-arm-linux-gnueabihf cpp-5-arm-linux-gnueabihf cpp-arm-linux-gnueabihf g++-multilib gcc-5-arm-linux-gnueabihf gcc-5-arm-linux-gnueabihf-base gcc-arm-linux-gnueabihf gcc-multilib libasan2-armhf-cross libatomic1-armhf-cross libgcc-5-dev-armhf-cross libgcc1-armhf-cross libgomp1-armhf-cross libstdc++6-armhf-cross libubsan0-armhf-cross
[...]
g++-multilib is already the newest version (4:5.3.1-1ubuntu1).
g++-multilib set to manually installed.
gcc-multilib is already the newest version (4:5.3.1-1ubuntu1).
gcc-multilib set to manually installed.
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 gcc-5-arm-linux-gnueabihf : Conflicts: gcc-multilib but 4:5.3.1-1ubuntu1 is to be installed
 gcc-multilib : Conflicts: gcc-5-arm-linux-gnueabihf:i386
                Conflicts: gcc-5-arm-linux-gnueabihf
E: Unable to correct problems, you have held broken packages.

I'm logging this to investigate it later because I've seen it before, some time ago, and ended up in this situation again but I don't know how this happened.

The fix (or work-around?) is "sudo apt remove gcc-multilib".