[gdb/testsuite] Warn about leaked global array

---
 gdb/testsuite/lib/gdb.exp | 54 +++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 54 insertions(+)

diff --git a/gdb/testsuite/lib/gdb.exp b/gdb/testsuite/lib/gdb.exp
index f7d20bd94f..91491a1f0f 100644
--- a/gdb/testsuite/lib/gdb.exp
+++ b/gdb/testsuite/lib/gdb.exp
@@ -5048,6 +5048,58 @@ proc standard_testfile {args} {
     }
 }
 
+# Returns 1 if __VAR is a global array.
+
+proc global_array_exists { __var } {
+    global $__var
+    return [array exists $__var]
+}
+
+# Unset global variable __VAR.
+
+proc global_unset { __var } {
+    global $__var
+    unset $__var
+}
+
+# Save global vars to variable gdb_global_vars.
+
+proc save_global_vars { test_file_name } {
+    global gdb_test_file_name
+    set gdb_test_file_name $test_file_name
+
+    global gdb_global_vars
+    set gdb_global_vars [list]
+
+    set gdb_global_vars [info globals]
+}
+
+# Check global variables not in gdb_global_vars.
+
+proc check_global_vars { } {
+    global gdb_global_vars
+    set vars [info globals]
+    set skip [list "expect_out" "spawn_out"]
+    foreach var $vars {
+        set found [lsearch -exact $gdb_global_vars $var]
+        if { $found != -1 } {
+            # Already present
+            continue
+        }
+        set found [lsearch -exact $skip $var]
+        if { $found != -1 } {
+            continue
+        }
+        if { ![global_array_exists $var] } {
+	    continue
+        }
+
+	global gdb_test_file_name
+        warning "$gdb_test_file_name.exp defined global array $var"
+        global_unset $var
+    }
+}
+
 # The default timeout used when testing GDB commands.  We want to use
 # the same timeout as the default dejagnu timeout, unless the user has
 # already provided a specific value (probably through a site.exp file).
@@ -5177,10 +5229,12 @@ proc gdb_init { test_file_name } {
     global gdb_instances
     set gdb_instances 0
 
+    save_global_vars $test_file_name
     return [default_gdb_init $test_file_name]
 }
 
 proc gdb_finish { } {
+    check_global_vars
     global gdbserver_reconnect_p
     global gdb_prompt
     global cleanfiles