[PATCH v8 5/6] gdb/infrun: enable/disable thread events of all targets in stop_all_threads

[Pedro Alves <palves@redhat.com>]

From: Tankut Baris Aktemur <tankut.baris.aktemur@intel.com>

In stop_all_threads, the thread events of the current top target are
enabled at the beginning of the function and then disabled at the end
(at scope exit time).  Because there may be multiple targets whose
thread lists will be updated and whose threads are stopped,
enable/disable thread events for all targets.

This update caused a change in the annotations.  In particular, a
"frames-invalid" annotation is printed one more time due to switching
the current inferior.  Hence, gdb.base/annota1.exp and
gdb.cp/annota2.exp tests are also updated.

Regression-tested on X86_64 Linux using the default board file and the
native-extended-gdbserver board file.

gdb/ChangeLog:
2020-04-30  Tankut Baris Aktemur  <tankut.baris.aktemur@intel.com>

	* infrun.c (stop_all_threads): Enable/disable thread events of all
	targets.

gdb/testsuite/ChangeLog:
2020-04-30  Tankut Baris Aktemur  <tankut.baris.aktemur@intel.com>

	* gdb.base/annota1.exp: Update the expected output.
	* gdb.cp/annota2.exp: Ditto.
---
 gdb/infrun.c                       | 15 +++++++++++++--
 gdb/testsuite/gdb.base/annota1.exp |  2 +-
 gdb/testsuite/gdb.cp/annota2.exp   |  2 +-
 3 files changed, 15 insertions(+), 4 deletions(-)

diff --git a/gdb/infrun.c b/gdb/infrun.c
index c5bf2d0ad74..6602bc28d5e 100644
--- a/gdb/infrun.c
+++ b/gdb/infrun.c
@@ -4769,8 +4769,12 @@ stop_all_threads (void)
 
   scoped_restore_current_thread restore_thread;
 
-  target_thread_events (1);
-  SCOPE_EXIT { target_thread_events (0); };
+  /* Enable thread events of all targets.  */
+  for (auto *target : all_non_exited_process_targets ())
+    {
+      switch_to_target_no_thread (target);
+      target_thread_events (true);
+    }
 
   /* Request threads to stop, and then wait for the stops.  Because
      threads we already know about can spawn more threads while we're
@@ -4962,6 +4966,13 @@ stop_all_threads (void)
 	}
     }
 
+  /* Disable thread events of all targets.  */
+  for (auto *target : all_non_exited_process_targets ())
+    {
+      switch_to_target_no_thread (target);
+      target_thread_events (false);
+    }
+
   if (debug_infrun)
     fprintf_unfiltered (gdb_stdlog, "infrun: stop_all_threads done\n");
 }
diff --git a/gdb/testsuite/gdb.base/annota1.exp b/gdb/testsuite/gdb.base/annota1.exp
index 9d3bf73431c..829d144cc20 100644
--- a/gdb/testsuite/gdb.base/annota1.exp
+++ b/gdb/testsuite/gdb.base/annota1.exp
@@ -223,7 +223,7 @@ gdb_test_multiple "break printf" "break printf" {
 #
 # get to printf
 #
-set pat_begin "\r\n\032\032post-prompt\r\nContinuing.\r\n\r\n\032\032starting\r\n\r\n\032\032frames-invalid\r\n${breakpoints_invalid}"
+set pat_begin "\r\n\032\032post-prompt\r\nContinuing.\r\n\r\n\032\032starting\r\n\r\n\032\032frames-invalid\r\n${breakpoints_invalid}\r\n\032\032frames-invalid\r\n"
 set pat_adjust "warning: Breakpoint 3 address previously adjusted from $hex to $hex.\r\n"
 set pat_end "\r\n\032\032breakpoint 3\r\n\r\nBreakpoint 3, \r\n\032\032frame-begin 0 $hex\r\n\r\n(\032\032frame-address\r\n$hex\r\n\032\032frame-address-end\r\n in \r\n)*.*\032\032frame-function-name\r\n.*printf(@.*)?\r\n\032\032frame-args\r\n.*\032\032frame-end\r\n\r\n\032\032stopped\r\n$gdb_prompt$"
 
diff --git a/gdb/testsuite/gdb.cp/annota2.exp b/gdb/testsuite/gdb.cp/annota2.exp
index dd3a0a5d6de..1b4f04bb445 100644
--- a/gdb/testsuite/gdb.cp/annota2.exp
+++ b/gdb/testsuite/gdb.cp/annota2.exp
@@ -218,7 +218,7 @@ set pat [multi_line "" \
 	     "\032\032post-prompt" \
 	     "" \
 	     "\032\032starting" \
-	     "\(${frames_invalid}\)*${breakpoints_invalid}" \
+	     "\(${frames_invalid}\)*${breakpoints_invalid}\(${frames_invalid}\)*" \
 	     "\032\032watchpoint 3" \
 	     ".*atchpoint 3: a.x" \
 	     "" \
-- 
2.14.5