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Gnu CC does support position independant code with the -fpic and -fPIC options. It is only supported when the compiler & assembler use the ELF object file format, it does not work when using COFF (as you have already discovered, judging from the listing you enclosed). ELF for the m68k will be supported in a forthcoming release of EGCS. There is an additional complication: the gnu implementation is designed with shared libraries in mind; it creates an address translation table which must be 'fixed up' at run time to point to the absolute address of functions and variables. This is not really useful for an embedded (diskless, OS-less) system. This is a more complicated issue, and it would take some work to implement for a low-end system (essentially you would need a run-time loader of some sort). FALE@skidata.com wrote: > > Hi, > > is it possible to generate position independent code > and data references with the gnu gcc for m68k/coldfire ? > > eg: > bsr function instead of jsr function > and > mov.l var(%a5),%d0 instead of move.l var,%d0 > > at the moment we use the sds crosscode c compiler > which has this option (register relative data and bss), > but can't generate code for the coldfire cpu. > > I tried the -fpic and -fPIC options and got the following > assembler output > > move.l %a5,-(%sp) > lea (%pc, _GLOBAL_OFFSET_TABLE_@GOTPC), %a5 > bsr __main@PLTPC > " > " > move.l var@GOT.w(%a5),%d1 > " > etc... > > and following assembler errors > temp.s: Assembler messages: > temp.s:55: Error: parse error -- statement `lea > (%pc,_GLOBAL_OFFSET_TABLE_@GOTPC),%a5' ignored > temp.s:56: Error: parse error -- statement `bsr __main@PLTPC' ignored > > seems the assembler does'nt understand the generated code ? > > any ideas ? > > Leopold Faschalek mailto:fale@skidata.com > Research and Development > SkiData AG http://www.skidata.com > Untersbergstrasse 40 > A-5083 Gartenau voice:+43-6246-888 > > _______________________________________________ > New CrossGCC FAQ: http://www.objsw.com/CrossGCC > _______________________________________________ > To remove yourself from the crossgcc list, send > mail to crossgcc-request@cygnus.com with the > text 'unsubscribe' (without the quotes) in the > body of the message. _______________________________________________ New CrossGCC FAQ: http://www.objsw.com/CrossGCC _______________________________________________ To remove yourself from the crossgcc list, send mail to crossgcc-request@cygnus.com with the text 'unsubscribe' (without the quotes) in the body of the message.