http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28896
--- Comment #19 from Larry Baker <baker at usgs dot gov> 2012-08-25 00:28:56 UTC --- I plan to start testing my patches on a ColdFire uClinux system on Monday. In the mean time, I am unsure whether my code is correct for the -fPIC -mno-sep-data case. I do not know if a5 is a volatile register, or if, instead, it must be saved/restored. It is possible (as shown by my example) that a5 might otherwise not be needed by the code in a procedure. In that case, my code is not enabling the save/restore of a5, which would be wrong if a5 is not volatile. This is not a problem for -msep-data (implies -fPIC), since a5 already has the correct value, and is not altered by my code. I will investigate whether a5 is volatile. If anyone knows the answer already, please add a comment. If anyone can recommend what has to be called or modified to force a5 to be saved/restored, I would appreciate hearing about that as well. Thank you, Larry Baker
