@Althaus,
Great, you are welcome to submit extension. Please send them to picoresubmit@gmail.com
Extension creation and submission rules are the same as for x86. Please study existing .info and follow style and content.
To make submitqc for piCore is not on my todo list, you are welcome to adapt it.
Toolchain is using properer architecture by default, no need to specify it. You can use
export CFLAGS="-Os -pipe"
export CXXFLAGS="-Os -pipe -fno-exceptions -fno-rtti"
In most cases it works, however program my require -fexceptions to build.
Also
export PKG_CONFIG_PATH=/usr/local/lib/pkgconfig:/usr/lib/pkgconfig
99% of my build scripts used on x86 works on piCore just removing -march and -mtune