PR target/47098 OBSD_LIB_SPEC on i686-openbsd3 missing

config-list.mk for i686-*-openbsd3.0 failed with:

gcc/config/openbsd.h:143:18: error: ‘OBSD_LIB_SPEC’ was not declared in this scope
 #define LIB_SPEC OBSD_LIB_SPEC
                  ^
gcc/gcc.c:879:31: note:
in expansion of macro ‘LIB_SPEC’
 static const char *lib_spec = LIB_SPEC;
                               ^
make[2]: *** [gcc.o] Error 1

i.e. openbsd-oldgas.h is only used on
i?86-*-openbsd2.*|i?86-*openbsd3.[0123] so add the OBSD_LIB_SPEC there

From-SVN: r222315

gcc/ChangeLog

 2015-04-22  Bernhard Reutner-Fischer  <aldot@gcc.gnu.org>
 
+	PR target/47098
+	* config/openbsd-oldgas.h (OBSD_LIB_SPEC): Add.
+
+2015-04-22  Bernhard Reutner-Fischer  <aldot@gcc.gnu.org>
+
 	PR target/47122
 	* config.gcc (vax-*-openbsd*): Fix name of pthread spec header.
 

gcc/config/openbsd-oldgas.h

@@ -20,3 +20,7 @@ along with GCC; see the file COPYING3.  If not see
 
 
 #define OBSD_OLD_GAS
+
+/* OpenBSD3.0 had no libpthread, pthreads lived in -lc_r */
+#define OBSD_LIB_SPEC "%{!shared:-lc%{pthread:_r}}"
+