diff --git a/fast/f_c.ansi/Parameters b/fast/f_c.ansi/Parameters
index 239e82c7e..2700280cf 100644
--- a/fast/f_c.ansi/Parameters
+++ b/fast/f_c.ansi/Parameters
@@ -122,7 +122,6 @@
 !File: spec_arith.h
 /* describes internal compiler arithmetics */
 /*#define	SPECIAL_ARITHMETICS	/* something different from native long */
-#define UNSIGNED_ARITH	unsigned arith	/* when it is supported */
 
 
 !File: static.h
diff --git a/fast/f_m2/Parameters b/fast/f_m2/Parameters
index 211ca9431..a2d5ea197 100644
--- a/fast/f_m2/Parameters
+++ b/fast/f_m2/Parameters
@@ -95,7 +95,3 @@
 /*#define USE_INSERT	1	/* use C_insertpart mechanism */
 
 
-!File: uns_arith.h
-#define UNSIGNED_ARITH	unsigned arith
-
-
diff --git a/lang/cem/lint/lpass1.ansi/Parameters b/lang/cem/lint/lpass1.ansi/Parameters
index 1e635829e..bf6c51871 100644
--- a/lang/cem/lint/lpass1.ansi/Parameters
+++ b/lang/cem/lint/lpass1.ansi/Parameters
@@ -123,7 +123,6 @@
 !File: spec_arith.h
 /* describes internal compiler arithmetics */
 /*#define	SPECIAL_ARITHMETICS	/* something different from native long */
-/*#define UNSIGNED_ARITH	unsigned arith	/* when it is supported */
 
 
 !File: static.h