Add comment for MEMCPY_OK_FOR_FWD_MEMMOVE

diff --git a/ChangeLog b/ChangeLog
index a9574c9..d5458c7 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2014-07-04  Siddhesh Poyarekar  <siddhesh@redhat.com>
+
+       * sysdeps/generic/memcopy.h: Add comment for
+       MEMCPY_OK_FOR_FWD_MEMMOVE.
+
 2014-07-04  Will Newton  <will.newton@linaro.org>
 
        * string/memchr.c: Merge from gnulib.

diff --git a/sysdeps/generic/memcopy.h b/sysdeps/generic/memcopy.h
index 45c5fcb..f7b9423 100644 (file)
--- a/sysdeps/generic/memcopy.h
+++ b/sysdeps/generic/memcopy.h
@@ -190,6 +190,9 @@ extern void _wordcopy_bwd_dest_aligned (long int, long int, size_t) __THROW;
 /* Threshold value for when to enter the unrolled loops.  */
 #define        OP_T_THRES      16
 
+/* Set to 1 if memcpy is safe to use for forward-copying memmove with
+   overlapping addresses.  This is 0 by default because memcpy implementations
+   are generally not safe for overlapping addresses.  */
 #define MEMCPY_OK_FOR_FWD_MEMMOVE 0
 
 #endif /* memcopy.h */