Michael Rausch <marausch@xxxxxxxxx> writes: > The direcive is of course "#pragma interrupt". > I expected it to instruct the compiler to generate a "return from > interrupt" instruction at the end of the routine, instead of a "return > from subroutine". > This is what happens for the SH2. > The PowerPC actually has a "rfi" instruction, but the compiler > silently ignores the directive; the generated assembly code is the > same and there is no "rfi" at the end of the routine. I don't see any support for #pragma interrupt in the PowerPC backend. I support for it in the SH backend, with a comment saying "Handle machine specific pragmas to be semi-compatible with Renesas compiler." I see the "interrupt" and "interrupt_handler" function attributes documented here: http://gcc.gnu.org/onlinedocs/gcc-3.4.2/gcc/Function-Attributes.html#Function-Attributes but the documentation does not indicate that they are supported on the PowerPC. Basically, I don't think there is any special support in the compiler for interrupt routines on the PowerPC. I assume most people just write the routines, or at least the wrappers, in assembly code. Ian