[PATCH v4 6/8] Call quit_force for gdb_exception_forced_quit in safe_execute_command

[Kevin Buettner <kevinb@redhat.com>]

In gdb/cli/cli-interp.c, safe_execute_command catches gdb_exception.
In the previous series, I had changed it to instead catch
gdb_exception_error, which would allow gdb_exception_quit and
gdb_exception_forced_quit to not be caught, thus propagating as
normal.

Pedro found some problems with doing this for safe_execute_command.
See:

https://sourceware.org/pipermail/gdb-patches/2022-March/186320.html

Pedro suggested: "Maybe we can just eliminate safe_execute_command and
let exceptions propagate normally."

I'm not doing that here, though I think it might be worth trying.

Instead, what I've done is to catch gdb_exception_forced_quit and,
when caught, call quit_force() thus forcing GDB to terminate.

After (re)reading Pedro's remarks, I think there's still a problem
with this area of the code (in which gdb_exception_quit is turned into
an error in interpreter_exec_cmd), but that problem existed before this
patch series and I think that fully addressing it should be the
subject of a different set of patches.

Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=26761
---
 gdb/cli/cli-interp.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/gdb/cli/cli-interp.c b/gdb/cli/cli-interp.c
index 5f2ff726f26..066e55b64f1 100644
--- a/gdb/cli/cli-interp.c
+++ b/gdb/cli/cli-interp.c
@@ -353,6 +353,17 @@ safe_execute_command (struct ui_out *command_uiout, const char *command,
     {
       execute_command (command, from_tty);
     }
+  catch (gdb_exception_forced_quit &exception)
+    {
+      /* Due to the way that the cli_inter::exec is structured, it is
+	 not safe to only catch gdb_exception_error below, thus
+	 allowing quit exceptions to propagate through.  (The CLI
+	 stream won't be reset as it should be.) So, for
+	 gdb_exception_forced_quit, which corresponds to GDB having
+	 received a SIGTERM signal, call quit_force() here which will
+	 cause GDB to terminate.  */
+      quit_force (NULL, 0);
+    }
   catch (gdb_exception &exception)
     {
       e = std::move (exception);
-- 
2.34.3