Linux-kernel mailing list archive 1999-25,: Re: Massive e2fs corruption with 2.2.9/10?

# Re: Massive e2fs corruption with 2.2.9/10?

Horst von Brand (vonbrand@inf.utfsm.cl)
Sun, 20 Jun 1999 23:34:39 -0400

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ron flory <rjflory@feist.com> said:

[...]

> It seems memcmp() is returning false miscompare status. If I use a
> for(){buf1[i] != buf2[i]} loop to scan the two read buffers after the
> memcmp() check, I find that the buffers are, in fact, identical. Now
> what ????

Compiler used? memcmp() used? Machine?

Note that the latest egcs snapshots by default enable optimizations based
on the assumption that only pointers to the same type can create aliases
(this according to ANSI C). The in-kernel mem* functions break this
assumption big time, probably other implementations do so too...

Try -fno-strict-aliasing

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    Dr. Horst H. von Brand                       mailto:vonbrand@inf.utfsm.cl
    Departamento de Informatica                     Fono: +56 32 654431
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