From 93d58cd3ed1cc2cf0490e95d43eed4e8de62763d Mon Sep 17 00:00:00 2001
From: William S Fulton <wsf@fultondesigns.co.uk>
Date: Sat, 20 Dec 2014 16:56:31 +0000
Subject: [PATCH] Fix use of preprocessor null directive

This was broken recently in commit 255c929c5636f54c16261bd92b8eea2005d61b11
for issue #217
---
 Examples/test-suite/preproc.i               | 17 +++++++++++++++++
 Examples/test-suite/python/preproc_runme.py |  2 ++
 Source/Preprocessor/cpp.c                   |  2 ++
 3 files changed, 21 insertions(+)

diff --git a/Examples/test-suite/preproc.i b/Examples/test-suite/preproc.i
index e052bff28..779c41e97 100644
--- a/Examples/test-suite/preproc.i
+++ b/Examples/test-suite/preproc.i
@@ -346,3 +346,20 @@ int method(struct TypeNameTraits tnt) {
   return tnt.val;
 }
 %}
+
+/* Null directive */
+# /* comment 1 */
+# // comment 2
+# /** comment 3 */
+# /* comment 4 */ /*comment 5*/
+# /** comment 6
+#
+# more comment 6 */
+# 
+#
+#	    
+int methodX(int x);
+%{
+int methodX(int x) { return x+100; }
+%}
+
diff --git a/Examples/test-suite/python/preproc_runme.py b/Examples/test-suite/python/preproc_runme.py
index c989294b6..3049f00ab 100644
--- a/Examples/test-suite/python/preproc_runme.py
+++ b/Examples/test-suite/python/preproc_runme.py
@@ -12,3 +12,5 @@ if preproc.defined != 1:
 if 2*preproc.one != preproc.two:
   raise RuntimeError
 
+if preproc.methodX(99) != 199:
+  raise RuntimeError
diff --git a/Source/Preprocessor/cpp.c b/Source/Preprocessor/cpp.c
index 1ca549703..b556bce27 100644
--- a/Source/Preprocessor/cpp.c
+++ b/Source/Preprocessor/cpp.c
@@ -1768,6 +1768,8 @@ String *Preprocessor_parse(String *s) {
 	}
       } else if (Equal(id, kpp_level)) {
 	Swig_error(Getfile(s), Getline(id), "cpp debug: level = %d, startlevel = %d\n", level, start_level);
+      } else if (Equal(id, "")) {
+	/* Null directive */
       } else {
 	Swig_error(Getfile(s), Getline(id), "Unknown SWIG preprocessor directive: %s\n", id);
       }