* dcrt0.cc (do_exit): Don't bother looking for pgrp children to send SIGHUP if

process has never created any children.
* fork.cc (fork): Set flag indicating that there is another process with our
process group.
* spawn.cc (spawn_guts): Ditto.
* pinfo.h (set_has_pgid_children): New methods for setting when process has
children in its process group.
* syscalls.cc (setpgid): Clear has_gid_children if pgid changes.

winsup/cygwin/pinfo.h

@@ -70,6 +70,7 @@ public:
   pid_t sid;		/* Session ID */
   int ctty;		/* Control tty */
   mode_t umask;
+  bool has_pgid_children;/* True if we've forked or spawned children with our GID. */
   char username[MAX_USER_NAME]; /* user's name */
 
   /* Extendend user information.
@@ -106,6 +107,14 @@ public:
 
   void exit (UINT n, bool norecord = 0) __attribute__ ((noreturn, regparm(2)));
 
+  inline void set_has_pgid_children ()
+  {
+    if (pgid == pid)
+      has_pgid_children = 1;
+  }
+
+  inline void set_has_pgid_children (bool val) {has_pgid_children = val;}
+
   inline struct sigaction& getsig (int sig)
   {
     return thread2signal ? thread2signal->sigs[sig] : sigs[sig];
@@ -158,7 +167,7 @@ public:
     if (destroy && procinfo)
       release ();
   }
-    
+
   _pinfo *operator -> () const {return procinfo;}
   int operator == (pinfo *x) const {return x->procinfo == procinfo;}
   int operator == (pinfo &x) const {return x.procinfo == procinfo;}