Throughout use "have_execed" macro rather than "hExeced" global handle.

Throughout rename _PROC_* to _CH_*.
* child_info.h: Include "pinfo.h".
(child_info_types): Rename _PROC_* -> _CH_* to avoid confusion with similarly
named constants.
(_PROC_*): Delete unneeded aliases.
(PROC_*): Ditto.
(CURR_CHILD_INFO_MAGIC): Ditto.
(cchildren): Define using "pinfo_minimal".
(child_info::set_saw_ctrl_c): Move to
(child_info_spawn::set_saw_ctrl_c): Here.
(child_info_spawn::lock): New field.
(child_info_spawn::hExeced): Ditto.
(child_info_spawn::ev): Ditto.
(child_info_spawn::~child_info_spawn): Move to sigproc.cc.
(child_info_spawn::child_info_spawn): Ditto.
(child_info_spawn::cleanup): Declare new function.
(child_info_spawn::set_saw_ctrl_c): Move to this class.  Set flag only when
execed and return true when we have set the flag.
(child_info_spawn::child_info_spawn::signal_myself_exited): New function.
(child_info_spawn::wait_for_myself): Ditto.
(child_info_spawn::has_execed_cygwin): Ditto.
(child_info_spawn::has_execed): Ditto.  Replaces "hExeced" test.
(child_info_spawn::operator HANDLE&): New operator.
(child_info_spawn::worker): Define old "spawn_guts" as class member.
(ch_spawn): Declare.
(have_execed): Define.
(have_execed_cygwin): Ditto.
* cygheap.h: Update comment.
* dcrt0.cc (get_cygwin_startup_info): Use _CH_* enums.
(child_info_spawn::handle_spawn): Ditto.
(dll_crt0_0): Ditto.
(multiple_cygwin_problem): Ditto.
* exceptions.cc (chExeced): Delete obsolete declaration.
(ctrl_c_handler): Reference set_saw_ctrl_c via new ch_spawn global.
* globals.cc (hExeced): Delete.
* pinfo.cc (pinfo::thisproc): Refer to cygheap as ::cygheap for consistency in
handle naming when -DDEBUGGING.
(pinfo::init): Accommodate case where myself.h is known but h0 is passed in.
(pinfo::pinfo): New constructor for setting up a pinfo passed in by previous
exec'or.
(pinfo::proc_waiter): Don't handle subprocess if we're in the process of
exiting due to an exec of a cygwin process.  Don't close rd_proc_pipe here.
Close it when we actually are finished with the process.  Use new
ch_spawn.signal_myself_exited function to let exec stub know that subprocess
has exited.
(pinfo::wait): Clarify debugging output.
(pinfo::release): Use "close_h" to close all handles to avoid races.
(winpids::add): Assume that elements of the array do not need to be zeroed and
are properly initialized or suffer problems on pinfo::release.  Don't close
hProcess since release does that now.
* pinfo.h: Update comment.
(pinfo_minimal): Move some elements from pinfo here so that child_info_spawn
can use them.
(pinfo): Inherit from pinfo_minimal.
(pinfo::pinfo): Modify to accommodate new pinfo_minimal.
(pinfo::allow_remove): New function.
* sigproc.cc (proc_subproc): Use boolean values for true/false.  Implement
PROC_EXEC_CLEANUP.
(proc_terminate): Set ppid = 1 since the procs list will only be iterated when
the process has not execed.  Don't do any cleanup here since it is now handled
in pinfo::release.
(sigproc_init): Initialize sync_proc_subproc earlier.
(child_info::child_info): Assume that all important fields are properly
initialized and avoid memset().
(child_info_spawn::child_info_spawn): Specifically test for execing and then
set up appropriate fields in the struct.
(child_info_spawn::cleanup): Define new function.
(child_info_spawn::record_children): Specifically test for being execed here.
Fill in pinfo_minimal part of children array.
(child_info_spawn::reattach_children): Use constructor to duplicate information
for previous exec'or.  Add more debugging output.
(remove_proc): Force deletion of thread when exiting due to exec.  Rely on
pinfo::cleanup in release.
* sigproc.h (PROC_EXEC_CLEANUP): New enum.
(PROC_DETACHED_CHILD): Delete.
* spawn.cc (chExeced): Delete.
(child_info_spawn::worker): Rename from spawn_guts.  Use elements of
child_info_spawn throughout rather than ch.whatever.  Use ::cygheap to refer to
global rather than element of child_info.  Use wait_for_myself() rather than
waitpid().  Call child_info_spawn::cleanup on function return.
(spawnve): Reflect movement of spawn_guts functionality into
child_info_spawn::worker.
* syscalls.cc (popen): Ditto.
* winsup.h (spawn_guts): Delete declaration.

winsup/cygwin/debug.cc

@@ -171,6 +171,7 @@ delete_handle (handle_list *hl)
 void
 debug_fixup_after_fork_exec ()
 {
+debug_printf ("BEFORE");
   /* No lock needed at this point */
   handle_list *hl;
   for (hl = &cygheap->debug.starth; hl->next != NULL; /* nothing */)
@@ -178,6 +179,7 @@ debug_fixup_after_fork_exec ()
       hl = hl->next;
     else
       delete_handle (hl);	// removes hl->next
+debug_printf ("AFTER");
 }
 
 static bool __stdcall