Probe catch syscall support

In 82075af2c14b1f8a54fa5796fb63f7ef23f98d9d (Implement 'catch syscall'
for gdbserver), only x86 is supported, but the test can still be run
on other linux targets, like aarch64 and ppc, with native-gdbserver.
This causes many new fails.

This patch removes the check on isnative and on target triplets.
Instead, we can insert catch point, and resume the program to see whether
catch syscall is supported or not.

gdb/testsuite:

2016-06-28  Yao Qi  <yao.qi@linaro.org>

	* gdb.base/catch-syscall.exp: Remove check on isnative and target
	triplets.  Start gdb, execute catch syscall, and continue.  Check
	gdb's output to determine catch syscall is supported.
diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index b7e30f5..8ce6ee8 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,3 +1,9 @@
+2016-06-28  Yao Qi  <yao.qi@linaro.org>
+
+	* gdb.base/catch-syscall.exp: Remove check on isnative and target
+	triplets.  Start gdb, execute catch syscall, and continue.  Check
+	gdb's output to determine catch syscall is supported.
+
 2016-06-27  Manish Goregaokar  <manish@mozilla.com>
 
 	* gdb.rust/simple.rs: Add test for returning unit in a function
diff --git a/gdb/testsuite/gdb.base/catch-syscall.exp b/gdb/testsuite/gdb.base/catch-syscall.exp
index 5679000..f3ab6cb 100644
--- a/gdb/testsuite/gdb.base/catch-syscall.exp
+++ b/gdb/testsuite/gdb.base/catch-syscall.exp
@@ -19,20 +19,6 @@
 # It was written by Sergio Durigan Junior <sergiodj@linux.vnet.ibm.com>
 # on September/2008.
 
-if { ![isnative] } then {
-    continue
-}
-
-# This shall be updated whenever 'catch syscall' is implemented
-# on some architecture.
-if { ![istarget "x86_64-*-linux*"] && ![istarget "i\[34567\]86-*-linux*"]
-     && ![istarget "powerpc-*-linux*"] && ![istarget "powerpc64-*-linux*"]
-     && ![istarget "sparc-*-linux*"] && ![istarget "sparc64-*-linux*"]
-     && ![istarget "mips*-linux*"] && ![istarget "arm*-linux*"]
-     && ![istarget "s390*-linux*"] && ![istarget "aarch64*-*-linux*"] } {
-     continue
-}
-
 standard_testfile
 
 if  { [prepare_for_testing ${testfile}.exp $testfile ${testfile}.c] } {
@@ -40,6 +26,35 @@
      return -1
 }
 
+# Check target supports catch syscall or not.
+clean_restart $binfile
+if ![runto_main] then {
+    fail "Can't run to main"
+    return
+}
+
+set test "catch syscall"
+gdb_test_multiple $test $test {
+    -re "The feature \'catch syscall\' is not supported.*\r\n$gdb_prompt $" {
+	unsupported "catch syscall isn't supported"
+	return -1
+    }
+    -re ".*$gdb_prompt $" {
+	pass $test
+    }
+}
+
+set test "check catch syscall"
+gdb_test_multiple "continue" $test {
+    -re ".*Your system does not support this type\r\nof catchpoint.*$gdb_prompt $" {
+	unsupported "catch syscall isn't supported"
+	return -1
+    }
+    -re ".*Catchpoint.*$gdb_prompt $" {
+      pass $test
+    }
+}
+
 # All (but the last) syscalls from the example code.  It is filled in
 # proc setup_all_syscalls.
 set all_syscalls { }