Content originally posted in LPCWare by Felix G on Tue Oct 27 03:49:50 MST 2015
Problem solved!
It actually was caused by one of the options i had selected, however it had nothing to do with the interworking itself...
The culprit is the link-time optimization option (-flto), which apparently doesn't work correctly in this particular combination (ARM library with interrupt, used in a Thumb project with -flto).