* child_info.h (child_info::sync): Pass pid and HANDLE rather than using pinfo.

(child_info::child_info): Accept an argument controlling whether to create
proc_subproc.
(child_info_spawn::child_info_spawn): Ditto.
* sigproc.cc (child_info::child_info): Ditto.
(child_info_spawn::child_info_spawn): Ditto.
(child_info::sync): Use passed in pid and HANDLE.
* fork.cc (fork_parent): Reflect additional arguments required for
child_info::sync.
* hookapi.cc (hook_or_detect_cygwin): Rename.  Change so that NULL 'fn'
argument just returns "true", indicating that program uses cygwin1.dll.
* spawn.cc (av::win16_exe): New element.
* spawn.cc (av::iscygwin): New element.
(av::fixup): New function.
(spawn_guts): Protect against SEGV.  Use fixup function to detect when it is
safe to wait for a spawned (as opposed to an execed) program.  Reflect changes
in child_info::sync arguments.
* external.cc (cygwin_internal): Reflect function renaming to
hook_or_detect_cygwin.
* cygheap.cc (cygheap_fixup_in_child): Close handle after debug fixup has been
done to prevent false positives in handle collision.
* exceptions.cc (try_to_debug): Notify debugger if already being debugged.

winsup/cygwin/winsup.h

@@ -255,6 +255,8 @@ extern "C" int __stdcall strcasematch (const char *s1, const char *s2) __attribu
 extern "C" int __stdcall strncasematch (const char *s1, const char *s2, size_t n) __attribute__ ((regparm(3)));
 extern "C" char *__stdcall strcasestr (const char *searchee, const char *lookfor) __attribute__ ((regparm(2)));
 
+void *hook_or_detect_cygwin (const char *, const void *) __attribute__ ((regparm (2)));
+
 /* Time related */
 void __stdcall totimeval (struct timeval *, FILETIME *, int, int);
 long __stdcall to_time_t (FILETIME *);