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Re: [m68k] asm regression with 3.3/3.4/3.5


Ian Lance Taylor <ian@wasabisystems.com> writes:

> Specifying register asm() only means that any reference to that
> variable will use the specified register.  It doesn't mean that gcc
> can't eliminate use of that variable.  Read the documentation about
> local register variables.  In particular, note this:
>     This option does not guarantee that GCC will generate code that
>     has this variable in the register you specify at all times.  You
>     may not code an explicit reference to this register in an `asm'
>     statement and assume it will always refer to this variable.

Glibc depends heavily on being able to force a specific register to be
able to do inline syscalls.

Andreas.

-- 
Andreas Schwab, SuSE Labs, schwab@suse.de
SuSE Linux AG, Maxfeldstraße 5, 90409 Nürnberg, Germany
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"And now for something completely different."


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