diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index 3878cfeb5..1bb191603 100644
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,3 +1,8 @@
+2013-01-21  Christopher Faylor  <me.cygwin2013@cgf.cx>
+
+	* cygerrno.h (__reg3): Define.
+	* cygmalloc.h (__reg3): Ditto.
+
 2013-01-21  Christopher Faylor  <me.cygwin2013@cgf.cx>
 
 	* cygerrno.h: Conditionally define __regN for cygserver.
diff --git a/winsup/cygwin/cygerrno.h b/winsup/cygwin/cygerrno.h
index 677b3b0af..64a32ddbd 100644
--- a/winsup/cygwin/cygerrno.h
+++ b/winsup/cygwin/cygerrno.h
@@ -19,8 +19,8 @@ details. */
 #ifndef __reg2
 # define __reg2 __stdcall __attribute__ ((regparm (2)))
 #endif
-#ifndef __reg2
-# define __reg2 __stdcall __attribute__ ((regparm (2)))
+#ifndef __reg3
+# define __reg3 __stdcall __attribute__ ((regparm (3)))
 #endif
 
 void __reg3 seterrno_from_win_error (const char *file, int line, DWORD code);
diff --git a/winsup/cygwin/cygmalloc.h b/winsup/cygwin/cygmalloc.h
index 1a0235d3a..bf3a6237b 100644
--- a/winsup/cygwin/cygmalloc.h
+++ b/winsup/cygwin/cygmalloc.h
@@ -17,8 +17,8 @@ extern "C" {
 #ifndef __reg2
 # define __reg2 __stdcall __attribute__ ((regparm (2)))
 #endif
-#ifndef __reg2
-# define __reg2 __stdcall __attribute__ ((regparm (2)))
+#ifndef __reg3
+# define __reg3 __stdcall __attribute__ ((regparm (3)))
 #endif
 void __reg1 dlfree (void *p);
 void __reg1 *dlmalloc (unsigned size);