[binutils-gdb/gdb-7.11-branch] Make gdb/linux-nat.c consider a waitstatus pending on the infrun side

[Pedro Alves <palves at sourceware dot org>]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=a0de87e7be6a58dfeb9bfb00172dbd975dabb72e

commit a0de87e7be6a58dfeb9bfb00172dbd975dabb72e
Author: Pedro Alves <palves@redhat.com>
Date:   Wed May 25 18:35:09 2016 +0100

    Make gdb/linux-nat.c consider a waitstatus pending on the infrun side
    
    Working on the fix for gdb/19828, I saw
    gdb.threads/attach-many-short-lived-threads.exp fail once in an
    unusual way.  Unfortunately I didn't keep debug logs, but it's an
    issue similar to what's been fixed in remote.c a while ago --
    linux-nat.c was not fetching the pending status from the right place.
    
    gdb/ChangeLog:
    2016-05-25  Pedro Alves  <palves@redhat.com>
    
    	PR gdb/19828
    	* linux-nat.c (get_pending_status): If the thread reported the
    	event to the core and it's pending, use the pending status signal
    	number.

Diff:
---
 gdb/ChangeLog   | 7 +++++++
 gdb/linux-nat.c | 5 ++++-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 3ee9cb4..179acf0 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,10 @@
+2016-05-25  Pedro Alves  <palves@redhat.com>
+
+	PR gdb/19828
+	* linux-nat.c (get_pending_status): If the thread reported the
+	event to the core and it's pending, use the pending status signal
+	number.
+
 2016-05-17  Simon Marchi  <simon.marchi@ericsson.com>
 
 	PR gdb/20045
diff --git a/gdb/linux-nat.c b/gdb/linux-nat.c
index 0829bcb..ea171b0 100644
--- a/gdb/linux-nat.c
+++ b/gdb/linux-nat.c
@@ -1236,7 +1236,10 @@ get_pending_status (struct lwp_info *lp, int *status)
     {
       struct thread_info *tp = find_thread_ptid (lp->ptid);
 
-      signo = tp->suspend.stop_signal;
+      if (tp->suspend.waitstatus_pending_p)
+	signo = tp->suspend.waitstatus.value.sig;
+      else
+	signo = tp->suspend.stop_signal;
     }
   else if (!target_is_non_stop_p ())
     {