* cygrun.c (main): Fix compiler warning.

* gmon.c (_mcleanup): Ditto.
* profil.c (profile_off): Ditto.
* net.cc (find_winsock_errno): New function.
(__set_winsock_errno): Use find_winsock_errno.
(cygwin_setsockopt): Detect SO_ERROR for debugging.
(cygwin_getsockopt): Ditto.  Translate error when getsockopt returns SO_ERROR.
* winsup.h: regparmize __set_winsock_errno.
* include/sys/strace.h: Document that strace functions can't use regparm.

winsup/cygwin/cygrun.c

@@ -15,6 +15,7 @@ details. */
 
 #include <stdio.h>
 #include <windows.h>
+#include <stdlib.h>
 
 int
 main(int argc, char **argv)
@@ -29,7 +30,7 @@ main(int argc, char **argv)
       exit (0);
     }
 
-  setenv("CYGWIN_TESTING", "1");
+  putenv("CYGWIN_TESTING=1");
   SetEnvironmentVariable("CYGWIN_TESTING", "1");
 
   memset(&sa, 0, sizeof(sa));