Isolate the C-compiler even more with env -i and -nostdinc

git-svn-id: http://www.varnish-cache.org/svn/trunk/varnish-cache@1870 d4fa192b-c00b-0410-8231-f00ffab90ce4

bin/varnishd/mgt_vcc.c

@@ -184,7 +184,7 @@ mgt_CallCc(const char *source, struct vsb *sb)
 #ifdef __APPLE__
 	    "exec cc -dynamiclib -Wl,-undefined,dynamic_lookup -o %s -x c - < %s 2>&1",
 #else
-	    "exec cc -fpic -shared -Wl,-x -o %s -x c - < %s 2>&1",
+	    "env -i cc -nostdinc -fpic -shared -Wl,-x -o %s -x c - < %s 2>&1",
 #endif
 	    sf, of, sf);
 	xxxassert(len < sizeof buf);