Ensure that clang is actually been used

Index: bootstrap
===================================================================
RCS file: /cvsroot/pkgsrc/bootstrap/bootstrap,v
retrieving revision 1.209
diff -u -r1.209 bootstrap
--- bootstrap	11 Jul 2014 17:29:21 -0000	1.209
+++ bootstrap	30 Jul 2014 15:43:24 -0000
@@ -159,8 +159,10 @@

 	cat >${wrkdir}/$$.c <<EOF
 #ifdef __GNUC__
+#ifndef __clang__
 indeed
 #endif
+#endif
 EOF
 	compiler_is_gnu=`${testcc:-cc} -E ${wrkdir}/$$.c 2>/dev/null | grep -c indeed`
 	rm -f ${wrkdir}/$$.c
@@ -519,12 +521,12 @@
 	need_sed=no
 	set_opsys=no
 	machine_arch=`uname -p`
-	CC=${CC:-"gcc -isystem /usr/include"}; export CC
+	CC=${CC:-"cc -isystem /usr/include"}; export CC
 	check_compiler=yes
 	osrev=`uname -r`
 	macosx_version=`echo $osrev | awk -F . '{ print "10."$1-4; }'`
 	case "$macosx_version" in
-	10.[7-8])
+	10.[7-9])
 		packagemaker=/Applications/PackageMaker.app/Contents/MacOS/PackageMaker
 		;;
 	10.[0-4])