Try to avoid malloc SEGVs on Cygwin.

* callproc.c, process.h (block_child_signal, unblock_child_signal):
Now extern.
* emacs.c (main): Catch SIGCHLD just before initializing gfilenotify.
* process.c (catch_child_signal): Block SIGCHLD while futzing with
the SIGCHLD handler, since the code is not atomic and (due to glib)
signals may be arriving now.
* sysdep.c (init_signals): Do not catch child signals here;
'main' now does that later, at a safer time.

Fixes: debbugs:14569

1 files changed, 2 insertions, 2 deletions

diff --git a/src/callproc.c b/src/callproc.c
index 745d58c45f4..f0aa8222342 100644
--- a/src/callproc.c
+++ b/src/callproc.c
@@ -84,7 +84,7 @@ static int synch_process_fd;
 
 /* Block SIGCHLD.  */
 
-static void
+void
 block_child_signal (void)
 {
   sigset_t blocked;
@@ -95,7 +95,7 @@ block_child_signal (void)
 
 /* Unblock SIGCHLD.  */
 
-static void
+void
 unblock_child_signal (void)
 {
   pthread_sigmask (SIG_SETMASK, &empty_mask, 0);