improve error handling

jtlc

@@ -27,22 +27,24 @@ def main(argv):
         sys.stderr.write(argv[0] + ': no input files\n')
         return 1
 
+    success = True
     ofiles = []
     for s in args.sources:
         tf = tempfile.NamedTemporaryFile(suffix = '.c', delete = False)
         tfname = tf.name
-        build(args, s, tf)
+        success = build(args, s, tf)
         tf.close()
+        if success:
             m = re.match('(.*)\.jtl', s)
             if m is not None:
                 ofname = m.group(1) + '.o'
             else:
                 ofname = s + '.o'
             do_compile(args, tfname, ofname)
-        os.unlink(tfname)
             ofiles.append(ofname)
+        os.unlink(tfname)
 
-    if not args.c:
+    if success and not args.c:
         do_link(args, ofiles)
 
     return 0