[commited] windows gdb: Fix -target-attach result

[Claudiu Zissulescu <claudiu.zissulescu-ianculescu@amd.com>]

This patch fixes a Windows issue with "-target-attach <pid>", where
"running" is emitted instead of "done". The "done" message should be
synchronous for "-target-attach", but "mi_proceeded" variable is
incorrectly set to "1" when clear_proceed_status(0, true) is
called. As a result, "mi_interp::on_about_to_proceed" sets mi_proceed
to 1, and later "mi_interp::on_resume" emits "running" instead of
"done".

Remove redundant clear_proceed_status(0) call (the notify argument is
set to true by default). The init_wait_for_inferior(), which runs on
the very next line, already calls clear_proceed_status (0, false). A
new test is added too.

Signed-off-by: Claudiu Zissulescu <claudiu.zissulescu-ianculescu@amd.com>
Approved-By: Pedro Alves <pedro@palves.net>
Approved-By: Simon Marchi <simon.marchi@efficios.com>
---
 gdb/testsuite/gdb.mi/mi-attach.c   | 37 ++++++++++++++++++++++++++++++
 gdb/testsuite/gdb.mi/mi-attach.exp | 33 ++++++++++++++++++++++++++
 gdb/windows-nat.c                  |  1 -
 3 files changed, 70 insertions(+), 1 deletion(-)
 create mode 100644 gdb/testsuite/gdb.mi/mi-attach.c
 create mode 100644 gdb/testsuite/gdb.mi/mi-attach.exp

diff --git a/gdb/testsuite/gdb.mi/mi-attach.c b/gdb/testsuite/gdb.mi/mi-attach.c
new file mode 100644
index 00000000000..0ec0a0c161f
--- /dev/null
+++ b/gdb/testsuite/gdb.mi/mi-attach.c
@@ -0,0 +1,37 @@
+/* Copyright 2026 Free Software Foundation, Inc.
+
+   This file is part of GDB.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#ifdef _WIN32
+#include <windows.h>
+#else
+#include <unistd.h>
+#endif
+
+int
+main (void)
+{
+  /* Sleep long enough (5 min) to be attached to.  */
+#ifdef _WIN32
+  Sleep (300000);
+#else
+  sleep (300);
+#endif
+  return 0;
+}
diff --git a/gdb/testsuite/gdb.mi/mi-attach.exp b/gdb/testsuite/gdb.mi/mi-attach.exp
new file mode 100644
index 00000000000..9c58ccb3728
--- /dev/null
+++ b/gdb/testsuite/gdb.mi/mi-attach.exp
@@ -0,0 +1,33 @@
+# Copyright 2026 Free Software Foundation, Inc.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+load_lib mi-support.exp
+set MIFLAGS "-i=mi"
+
+require can_spawn_for_attach
+
+standard_testfile
+
+if {[build_executable "failed to prepare" $testfile $srcfile {debug}]} {
+    return
+}
+
+set spawn_id [spawn_wait_for_attach $::binfile]
+set prog_pid [spawn_id_get_pid $spawn_id]
+
+mi_clean_restart
+
+mi_gdb_test "-target-attach $prog_pid" ".*\\^done.*" "attach \$PROG_PID"
+kill_wait_spawned_process $spawn_id
diff --git a/gdb/windows-nat.c b/gdb/windows-nat.c
index d9e924f16c6..f1660a02175 100644
--- a/gdb/windows-nat.c
+++ b/gdb/windows-nat.c
@@ -1944,7 +1944,6 @@ windows_nat_target::do_initial_windows_stuff (DWORD pid, bool attaching)
   if (!inf->target_is_pushed (this))
     inf->push_target (this);
   windows_clear_solib ();
-  clear_proceed_status (0);
   init_wait_for_inferior ();
 
   inferior_appeared (inf, pid);
-- 
2.54.0