c/10339: strncmp generates imPure code

[Andreas Schwab]

Michael Ubell <ubell@mindspring.com> writes:

|> Do you mean you want me to set up a case where it runs off the
|> end of memory?

Yes.

|> I think it is sufficient that it is reading memory
|> that is not allocated, no?

No, it is not.

|>  If you change the length of the string
|> in the example you can see that it will read more unallocated
|> memory.

You haven't provided any evidence yet.  The provided test case is
correctly translated for the given platform.

|>  Do you have some reason why reading arbirary unallocated
|> memory is acceptable?  I don't see how the alignment is an issue.

It is.  Memory returned by malloc is required to be correctly aligned for
any type.

Andreas.

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Andreas Schwab, SuSE Labs, schwab@suse.de
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