Fix gdb.base/attach.exp --pid test skipping on native-extended-gdbserver

When testing with the native-extended-gdbserver board,
gdb.base/attach.exp shows a couple failures, like so:

 Running /home/pedro/gdb/src/gdb/testsuite/gdb.base/attach.exp ...
 FAIL: gdb.base/attach.exp: do_command_attach_tests: gdb_spawn_attach_cmdline: start gdb with --pid
 FAIL: gdb.base/attach.exp: do_command_attach_tests: gdb_spawn_attach_cmdline: info thread (no thread)

From gdb.log:

 builtin_spawn /home/pedro/gdb/build/gdb/testsuite/../../gdb/gdb -nw -nx -q -iex set height 0 -iex set width 0 -data-directory /home/pedro/gdb/build
 /gdb/data-directory -iex set auto-connect-native-target off -iex set sysroot -quiet --pid=2115260
 Don't know how to attach.  Try "help target".
 (gdb) FAIL: gdb.base/attach.exp: do_command_attach_tests: gdb_spawn_attach_cmdline: start gdb with --pid

There is a check for [isnative] to skip the test on anything but
target native, but that is the wrong check.  native-extended-gdbserver
is "isnative".  Fix it by using a gdb_protocol check instead.

Change-Id: I37ee730b8d6f1913b12c118838f511bd1c0b3768
Approved-By: Tom Tromey <tom@tromey.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/gdb/testsuite/gdb.base/attach.exp b/gdb/testsuite/gdb.base/attach.exp
index 637f287..831e11f 100644
--- a/gdb/testsuite/gdb.base/attach.exp
+++ b/gdb/testsuite/gdb.base/attach.exp
@@ -445,7 +445,9 @@ proc_with_prefix do_command_attach_tests {} {
     global gdb_prompt
     global binfile
 
-    if {![isnative]} {
+    # The --pid option is used to attach to a process using the native
+    # target.
+    if { ![gdb_protocol_is_native] } {
 	unsupported "command attach test"
 	return 0
     }