extend.texi: Document behavior of __attribute__((aligned)) on typedefs.

	* doc/extend.texi: Document behavior of __attribute__((aligned))
	on typedefs.

From-SVN: r125747

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index be3b820705ccee41a3c0ed102cbaafe26c0567bf..72c8dbb310614eadb86e12dcded652253f660f95 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2007-06-15  Matthew Wilcox <matthew@wil.cx>
+
+       * doc/extend.texi: Document behavior of __attribute__((aligned))
+       on typedefs.
+       
 2007-06-15  Mark Mitchell  <mark@codesourcery.com>
 
        * rtlanal.c (note_stores): Improve documentation.

diff --git a/gcc/doc/extend.texi b/gcc/doc/extend.texi
index baeff309adfcc8e053a7d244f7f97e046b272e74..c957757be10be377e64e3e9d5deb5760a5515623 100644 (file)
--- a/gcc/doc/extend.texi
+++ b/gcc/doc/extend.texi
@@ -3153,8 +3153,11 @@ copy operations more efficient, because the compiler can use whatever
 instructions copy the biggest chunks of memory when performing copies to
 or from the variables or fields that you have aligned this way.
 
-The @code{aligned} attribute can only increase the alignment; but you
-can decrease it by specifying @code{packed} as well.  See below.
+When used on a struct, or struct member, the @code{aligned} attribute can
+only increase the alignment; in order to decrease it, the @code{packed}
+attribute must be specified as well.  When used as part of a typedef, the
+@code{aligned} attribute can both increase and decrease alignment, and
+specifying the @code{packed} attribute will generate a warning.
 
 Note that the effectiveness of @code{aligned} attributes may be limited
 by inherent limitations in your linker.  On many systems, the linker is