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Re: m68k padding between methods at ld time


Ian Lance Taylor wrote:
Nick Clifton <nickc@redhat.com> writes:

Hi Joel,

Thanks. I do not have a tree for writing checked out at the
moment. Attached is the patch.
Just to be clear - why do you want NOP instructions rather than RTS
instructions ?

In the general case, you need to have nop instructions because of sections like .init and .fini which are built up from several object files and in which the flow of control must go from one object file to the next. Alignment may introduce gaps between the sections, and the linker must fill those gaps with nops.

Whether this ever happens on the m68k in particular I don't know.

I saw gaps between methods and they were being filled
with rts (0x4e75) instead of nop (0x4e71).

The definition of NOP in the emulparams file was for
the rts opcode not a nop opcode.

--joel
Ian


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