diff --git a/bin/sh/arith.h b/bin/sh/arith.h
index 352969e6ca86..569d0c58651f 100644
--- a/bin/sh/arith.h
+++ b/bin/sh/arith.h
@@ -35,4 +35,3 @@
 #define DIGITS(var) (3 + (2 + CHAR_BIT * sizeof((var))) / 3)
 
 arith_t arith(const char *);
-void arith_lex_reset(void);