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Re: [PATCH] commit-slab: sizeof() the right type in xrealloc

From
Jeff King <peff@peff.net>
Date
Dec 2, 2013, 15:35 UTC
Message-ID
<20131202153513.GA24202@sigill.intra.peff.net>
In-Reply-To
<87siucpalo.fsf_-_@linux-1gf2.Speedport_W723_V_Typ_A_1_00_098>
On Sun, Dec 01, 2013 at 09:41:55PM +0100, Thomas Rast wrote:
> When allocating the slab, the code accidentally computed the array
> size from s->slab (an elemtype**).  The slab is an array of elemtype*,
> however, so we should take the size of *s->slab.
Looks obviously correct.
Show 9 quoted lines
> I browsed around for a while, and couldn't find out whether any
> architecture actually has any hope of running git (i.e. is at least
> mostly POSIX conformant) but still violates the assumption that all
> pointers[*] are the same size.
> 
> The comp.lang.c FAQ has some interesting examples of wildly different
> pointer representations at:
> 
>   http://c-faq.com/null/machexamp.html

Note that most of those examples are not different sizes, but rather different null-pointer representations. We are already grossly out of compliance with the standard there, as we typically use memset() to zero-out structs with pointers.

-Peff
Previous: Thomas Rast
Message 18 of 18 in “commit-slab cleanups”
  1. 0/2 commit-slab cleanupsThomas Rast, Nov 25, 2013
  2. 1/2 commit-slab: document clear_$slabname()Thomas Rast, Nov 25, 2013
  3. Jonathan NiederNov 25, 2013
  4. Thomas RastNov 29, 2013
  5. Junio C HamanoNov 25, 2013
  6. Eric SunshineNov 27, 2013
  7. 2/2 commit-slab: declare functions "static inline"Thomas Rast, Nov 25, 2013
  8. Junio C HamanoNov 25, 2013
  9. Thomas RastNov 25, 2013
  10. commit-slab: declare functions "static inline"Thomas Rast, Nov 25, 2013
  11. Jonathan NiederNov 25, 2013
  12. Thomas RastNov 25, 2013
  13. Jonathan NiederNov 25, 2013
  14. Junio C HamanoNov 25, 2013
  15. Junio C HamanoNov 25, 2013
  16. Duy NguyenDec 1, 2013
  17. commit-slab: sizeof() the right type in xreallocThomas Rast, Dec 1, 2013
  18. Jeff KingDec 2, 2013

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