1 files changed, 18 insertions, 5 deletions

diff --git a/gcc/doc/extend.texi b/gcc/doc/extend.texi
index 882c082..30eae4b 100644
--- a/gcc/doc/extend.texi
+++ b/gcc/doc/extend.texi
@@ -1131,6 +1131,14 @@ such an initializer, as shown here:
 char **foo = (char *[]) @{ "x", "y", "z" @};
 @end smallexample
 
+As a GNU extension, GCC allows compound literals with a variable size.
+In this case, only empty initialization is allowed.
+
+@smallexample
+int n = 4;
+char (*p)[n] = &(char[n])@{ @};
+@end smallexample
+
 Compound literals for scalar types and union types are also allowed.  In
 the following example the variable @code{i} is initialized to the value
 @code{2}, the result of incrementing the unnamed object created by
@@ -7311,11 +7319,16 @@ the attribute.
 When the field that represents the number of the elements is assigned a
 negative integer value, the compiler treats the value as zero.
 
-The @code{counted_by} attribute is not allowed for a pointer to @code{void},
-a pointer to function, or a pointer to a structure or union that includes
-a flexible array member.  However, it is allowed for a pointer to
-non-void incomplete structure or union types, as long as the type could
-be completed before the first reference to the pointer.
+The @code{counted_by} attribute is not allowed for a pointer to function,
+or a pointer to a structure or union that includes a flexible array member.
+However, it is allowed for a pointer to non-void incomplete structure
+or union types, as long as the type could be completed before the first
+reference to the pointer.
+
+The attribute is allowed for a pointer to @code{void}.  However,
+warnings will be issued for such cases when @option{-Wpointer-arith} is
+specified.  When this attribute is applied on a pointer to @code{void},
+the size of each element of this pointer array is treated as 1.
 
 An explicit @code{counted_by} annotation defines a relationship between
 two objects, @code{p->array} and @code{p->count}, and there are the