This patch provides the "_Unwind_Backtrace" and "_Unwind_GetIPInfo" 
symbols required to link programs using libgfortran.

I do not wish to implement proper backtracing at this time (I have other 
things to work on), and IIUC none of the existing implementations will 
Just Work.

OK to commit?

-- 
Andrew Stubbs
Mentor Graphics / CodeSourcery