Index: cddl/contrib/opensolaris/lib/libdtrace/common/dt_lex.l
===================================================================
--- cddl/contrib/opensolaris/lib/libdtrace/common/dt_lex.l
+++ cddl/contrib/opensolaris/lib/libdtrace/common/dt_lex.l
@@ -64,7 +64,7 @@
 		result = n; \
 	}
 /*
- * Do not EOF let tokens to be put back. This does not work with flex.
+ * Do not let EOF tokens be put back. This does not work with flex.
  * On the other hand, leaving current buffer in same state it was when
  * last EOF was received guarantees that input() will keep returning EOF
  * for all subsequent invocations, which is the effect desired.
@@ -73,7 +73,7 @@
 #define unput(c)					\
 	do {						\
 		int _c = c;				\
-		if (_c != EOF)				\
+		if (_c != 0)				\
 			yyunput(_c, yytext_ptr);	\
 	} while(0)
 #endif