does gcc 4.x accept hardware register variables? Any restrictions?

biffle · 07-22-2008, 07:17 PM

gcc 4.2.1 and up do not correctly compile my programs with hardware register variables, both for 32-bit and 64-bit PCs. Is mthis feature no longer supported? It worked well under gcc 3.x.

kundor · 07-23-2008, 02:27 PM

They are still in the docs.

http://gcc.gnu.org/onlinedocs/gcc-4....-Reg-Vars.html

biffle · 07-25-2008, 04:07 PM

- thank you so much. Will try - biffle

biffle · 07-25-2008, 04:12 PM

- yes, I have that document. But global register variables still will not work (they report "register clobbered" when you try it with the 32-bit compilation.

With the 64-bit compilation (which can use new registers like r14) it works perfectly.

All this used FEDORA 8.

biffle