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Re: [PATCH 2/4] short circuit out of a few places where we would allocate zero bytes

From
Linus Torvalds <torvalds@osdl.org>
Date
Dec 28, 2005, 04:38 UTC
Message-ID
<Pine.LNX.4.64.0512272036380.14098@g5.osdl.org>
In-Reply-To
<43B21312.50603@zytor.com>
On Tue, 27 Dec 2005, H. Peter Anvin wrote:
> 
> Better yet, either always return NULL or allocate 1 byte in that case, to get
> consistent behaviour.

Yes. However, if you do the "return NULL" case (which is nicest), you'll have to wrap "free()" too. There are some libraries where passing "free()" a NULL pointer causes a SIGSEGV.

That said, I think that would be preferable to changing the source code to unnecessarily avoid zero-sized allocations. Having a "xfree()" to match "xmalloc()" makes sense. 

		Linus
Previous: H. Peter AnvinNext: Junio C Hamano
Message 7 of 24 in “dietlibc compatibility”
  1. 0/4 dietlibc compatibilityEric Wong, Dec 24, 2005
  2. 1/4 git.c: extra #include for dietlibc (and possibly other C libraries)Eric Wong, Dec 24, 2005
  3. Junio C HamanoDec 26, 2005
  4. 2/4 short circuit out of a few places where we would allocate zero bytesEric Wong, Dec 24, 2005
  5. Johannes SchindelinDec 24, 2005
  6. H. Peter AnvinDec 28, 2005
  7. Linus TorvaldsDec 28, 2005
  8. Junio C HamanoDec 28, 2005
  9. H. Peter AnvinDec 28, 2005
  10. 3/4 add xmktime() function that always accounts for the TZ envEric Wong, Dec 24, 2005
  11. Johannes SchindelinDec 24, 2005
  12. Junio C HamanoDec 24, 2005
  13. Eric WongDec 24, 2005
  14. Junio C HamanoDec 24, 2005
  15. 4/4 git-compat-util.h: dietlibc-friendly x{malloc,realloc,calloc}Eric Wong, Dec 24, 2005
  16. Junio C HamanoDec 24, 2005
  17. Eric WongDec 24, 2005
  18. Avoid allocating 0 bytes, was Re: [PATCH 4/4] git-compat-util.h: dietlibc-friendly x{malloc,realloc,calloc}Johannes Schindelin, Dec 26, 2005
  19. Junio C HamanoDec 26, 2005
  20. Johannes SchindelinDec 26, 2005
  21. avoid asking ?alloc() for zero bytes.Junio C Hamano, Dec 26, 2005
  22. Johannes SchindelinDec 26, 2005
  23. Johannes SchindelinDec 28, 2005
  24. Eric WongDec 30, 2005

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