This is the mail archive of the crossgcc@cygnus.com mailing list for the crossgcc project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]

Re: position independent code


At 05:24 PM 2/5/99 -0800, Scott Howard wrote:
>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).

I thought that many people were successfully using Gnu tools for embedded
work.  Is this "fix up" feature only included when -fPIC is used?  Or is it
only present with EGCS?  (I don't need position independent code.  In fact,
I want exactly the opposite. :-)


-=O=- Randy

In "A Scanner Darkly," was Philip K. Dick foreshadowing Web commerce:
"Someday, he thought, it'll be mandatory that we all sell the McDonald's
hamburger as well as buy it; we'll sell it back and forth to each other
forever from our living rooms." 
_______________________________________________
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.