-ffixed-di vs. strlen

[Richard Henderson]

On Fri, Feb 13, 2004 at 02:40:37PM -0500, Ian Lance Taylor wrote:
> The problem in this test case is arising with variables which are
> local to a function but are dedicated to a specific register during
> that function.  I don't think these are tracked anywhere at present.

No they aren't.  If this is what the test case does, then I misunderstood
and I revise my assessment.  They don't mean the same thing as variables
external to the function.  They do *not* reserve the register, they merely
provide access to it.  If it gets clobbered, then it gets clobbered.

This feature is only usable in extremely restricted circumstances.
You really really have to know what you are doing.  If it weren't for
the fact that the feature is essential for implementing system call
stubs, I might consider deprecating it.

As for generating a sensible "don't do that" error message, I'm not
really sure how to approach that.  Much of the information that you
might have liked to determine this has been thrown away, afaik.


r~