mirror/gcc
2
0
Fork 0
mirror of git://gcc.gnu.org/git/gcc.git synced 2025-04-05 16:51:13 +08:00
Code Issues Packages Projects Releases Wiki Activity

re PR other/56955 (documentation for attribute malloc contradicts itself)

Browse Source 
2014-05-22  Paul Eggert  <eggert@cs.ucla.edu>

	PR other/56955
	* doc/extend.texi (Function Attributes): Fix  __attribute__ ((malloc))
	documentation; the old documentation didn't clearly state the
	constraints on the contents of the pointed-to storage.

From-SVN: r210848
This commit is contained in:
Paul Eggert 2014-05-23 10:11:03 +00:00 committed by Richard Biener
parent 803e4cbb22
commit ee526ea745
2 changed files with 17 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
gcc/ChangeLog
View File

@ -1,3 +1,10 @@
2014-05-23 Paul Eggert <eggert@cs.ucla.edu>
PR other/56955
* doc/extend.texi (Function Attributes): Fix __attribute__ ((malloc))
documentation; the old documentation didn't clearly state the
constraints on the contents of the pointed-to storage.
2014-05-23 Maxim Kuvyrkov <maxim.kuvyrkov@linaro.org>
Fix bootstrap error on ia64

18
gcc/doc/extend.texi
View File

@ -3207,14 +3207,16 @@ efficient @code{jal} instruction.
@item malloc
@cindex @code{malloc} attribute
The @code{malloc} attribute is used to tell the compiler that a function
may be treated as if any non-@code{NULL} pointer it returns cannot
alias any other pointer valid when the function returns and that the memory
has undefined content.
This often improves optimization.
Standard functions with this property include @code{malloc} and
@code{calloc}. @code{realloc}-like functions do not have this
property as the memory pointed to does not have undefined content.
This tells the compiler that a function is @code{malloc}-like, i.e.,
that the pointer @var{P} returned by the function cannot alias any
other pointer valid when the function returns, and moreover no
pointers to valid objects occur in any storage addressed by @var{P}.
Using this attribute can improve optimization. Functions like
@code{malloc} and @code{calloc} have this property because they return
a pointer to uninitialized or zeroed-out storage. However, functions
like @code{realloc} do not have this property, as they can return a
pointer to storage containing pointers.
@item mips16/nomips16
@cindex @code{mips16} attribute