[newlib-cygwin] Cygwin: Fix signal handling issue introduced by PTY related change.

[Ken Brown]

https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=df5c79f30c3f871b7e0edd6d4629af78b30fca15

commit df5c79f30c3f871b7e0edd6d4629af78b30fca15
Author: Takashi Yano <takashi.yano@nifty.ne.jp>
Date:   Thu Oct 3 19:43:37 2019 +0900

    Cygwin: Fix signal handling issue introduced by PTY related change.
    
    - After commit 41864091014b63b0cb72ae98281fa53349b6ef77, there is a
      regression in signal handling reported in
      https://www.cygwin.com/ml/cygwin/2019-10/msg00010.html. This patch
      fixes the issue.

Diff:
---
 winsup/cygwin/exceptions.cc | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/winsup/cygwin/exceptions.cc b/winsup/cygwin/exceptions.cc
index db0fe08..132fea4 100644
--- a/winsup/cygwin/exceptions.cc
+++ b/winsup/cygwin/exceptions.cc
@@ -949,7 +949,7 @@ _cygtls::interrupt_setup (siginfo_t& si, void *handler, struct sigaction& siga)
   if (incyg)
     set_signal_arrived ();
 
-  if (!have_execed && ch_spawn.iscygwin ())
+  if (!have_execed && !(myself->exec_sendsig && !ch_spawn.iscygwin ()))
     proc_subproc (PROC_CLEARWAIT, 1);
   sigproc_printf ("armed signal_arrived %p, signal %d",
 		  signal_arrived, si.si_signo);