ASN1C

asn1c compiler
example patch:

diff -uw libasn1compiler/asn1c_misc.c.old libasn1compiler/asn1c_misc.c
--- libasn1compiler/asn1c_misc.c.old 2009-04-20 22:56:12.000000000 +0400
+++ libasn1compiler/asn1c_misc.c 2009-04-20 22:58:47.000000000 +0400
@@ -16,7 +16,7 @@
  "enum", "union", "struct", "typedef", "class",
  "switch", "case", "default", "break", "continue",
  "if", "else", "do", "for", "while", "goto",
- "sizeof", "return"
+ "sizeof", "return", "and", "or", "not", "xor"
 };
 static int
 reserved_keyword(const char *str) {

Full patch published there