Add testcase for stub-method reading in stabs.

This patch is based on the testcase provided here:
https://sourceware.org/ml/gdb-patches/2015-02/msg00181.html

I've verified that it catches the internal error discovered here:
https://sourceware.org/ml/gdb-patches/2015-02/msg00139.html

gdb/testsuite/ChangeLog:

	* lib/gdb.exp (clean_restart): Return result of gdb_load.
	* gdb.pascal/stub-method.exp: New file.
	* gdb.pascal/stub-method.pas: New file.

gdb/testsuite/gdb.pascal/stub-method.exp

@@ -0,0 +1,30 @@
+# Copyright 2007-2015 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/>.
+
+# Test loading of a file that when compiled with stabs uses a stub method.
+# This exercises gdbtypes.c:allocate_stub_method.
+
+load_lib "pascal.exp"
+
+standard_testfile .pas
+
+if {[gdb_compile_pascal "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable [list debug ]] != "" } {
+  return -1
+}
+
+# If this fails, the failure will have already been recorded.
+if { [clean_restart ${testfile}] == 0 } {
+    pass "loading file with stub method"
+}

gdb/testsuite/gdb.pascal/stub-method.pas

@@ -0,0 +1,33 @@
+{
+ Copyright 2015 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/>.
+}
+
+type
+  tobj = object
+constructor create;
+end;
+
+constructor tobj.create;
+
+begin
+end;
+
+var
+   t :  tobj;
+
+begin
+   t.create;
+end.

gdb/testsuite/lib/gdb.exp

@@ -4711,6 +4711,7 @@ proc build_executable { testname executable {sources ""} {options {debug}} } {
 
 # Starts fresh GDB binary and loads EXECUTABLE into GDB. EXECUTABLE is
 # the basename of the binary.
+# The return value is 0 for success, -1 for failure.
 proc clean_restart { executable } {
     global srcdir
     global subdir
@@ -4719,7 +4720,7 @@ proc clean_restart { executable } {
     gdb_exit
     gdb_start
     gdb_reinitialize_dir $srcdir/$subdir
-    gdb_load ${binfile}
+    return [gdb_load ${binfile}]
 }
 
 # Prepares for testing by calling build_executable_full, then