diff --git a/bootstrap/unix-44/OPS.c b/bootstrap/unix-44/OPS.c
index 5243ea65..29ea2414 100644
--- a/bootstrap/unix-44/OPS.c
+++ b/bootstrap/unix-44/OPS.c
@@ -17,7 +17,7 @@ typedef
 export OPS_Name OPS_name;
 export OPS_String OPS_str;
 export int16 OPS_numtyp;
-export int64 OPS_intval;
+export int32 OPS_intval;
 export REAL OPS_realval;
 export LONGREAL OPS_lrlval;
 static CHAR OPS_ch;
@@ -178,7 +178,7 @@ static void OPS_Number (void)
 				OPS_numtyp = 1;
 				if (n <= 2) {
 					while (i < n) {
-						OPS_intval = __ASHL(OPS_intval, 4) + (int64)Ord__7(dig[i], 1);
+						OPS_intval = __ASHL(OPS_intval, 4) + Ord__7(dig[i], 1);
 						i += 1;
 					}
 				} else {
@@ -192,7 +192,7 @@ static void OPS_Number (void)
 						OPS_intval = -1;
 					}
 					while (i < n) {
-						OPS_intval = __ASHL(OPS_intval, 4) + (int64)Ord__7(dig[i], 1);
+						OPS_intval = __ASHL(OPS_intval, 4) + Ord__7(dig[i], 1);
 						i += 1;
 					}
 				} else {
@@ -203,8 +203,8 @@ static void OPS_Number (void)
 				while (i < n) {
 					d = Ord__7(dig[i], 0);
 					i += 1;
-					if (OPS_intval <= (int64)__DIV(9223372036854775807 - d, 10)) {
-						OPS_intval = OPS_intval * 10 + (int64)d;
+					if ((int64)OPS_intval <= __DIV(9223372036854775807 - (int64)d, 10)) {
+						OPS_intval = OPS_intval * 10 + d;
 					} else {
 						OPS_err(203);
 					}
diff --git a/bootstrap/unix-44/OPS.h b/bootstrap/unix-44/OPS.h
index af53d634..57cf06d3 100644
--- a/bootstrap/unix-44/OPS.h
+++ b/bootstrap/unix-44/OPS.h
@@ -15,7 +15,7 @@ typedef
 import OPS_Name OPS_name;
 import OPS_String OPS_str;
 import int16 OPS_numtyp;
-import int64 OPS_intval;
+import int32 OPS_intval;
 import REAL OPS_realval;
 import LONGREAL OPS_lrlval;
 
diff --git a/bootstrap/unix-44/OPT.c b/bootstrap/unix-44/OPT.c
index a12c1a7f..62ff8882 100644
--- a/bootstrap/unix-44/OPT.c
+++ b/bootstrap/unix-44/OPT.c
@@ -167,11 +167,14 @@ OPT_Struct OPT_IntType (int32 size)
 	OPT_Struct _o_result;
 	int16 i;
 	i = 1;
-	while ((OPT_IntTypes[__X(i, 20)]->size < size && OPT_IntTypes[__X(i + 1, 20)] != NIL)) {
+	while (i < 19) {
+		if ((OPT_IntTypes[__X(i, 20)] != NIL && OPT_IntTypes[__X(i, 20)]->size >= size)) {
+			_o_result = OPT_IntTypes[__X(i, 20)];
+			return _o_result;
+		}
 		i += 1;
 	}
-	_o_result = OPT_IntTypes[__X(i, 20)];
-	return _o_result;
+	__RETCHK;
 }
 
 OPT_Struct OPT_ShorterOrLongerType (OPT_Struct x, int16 dir)
diff --git a/bootstrap/unix-48/OPS.c b/bootstrap/unix-48/OPS.c
index 5243ea65..29ea2414 100644
--- a/bootstrap/unix-48/OPS.c
+++ b/bootstrap/unix-48/OPS.c
@@ -17,7 +17,7 @@ typedef
 export OPS_Name OPS_name;
 export OPS_String OPS_str;
 export int16 OPS_numtyp;
-export int64 OPS_intval;
+export int32 OPS_intval;
 export REAL OPS_realval;
 export LONGREAL OPS_lrlval;
 static CHAR OPS_ch;
@@ -178,7 +178,7 @@ static void OPS_Number (void)
 				OPS_numtyp = 1;
 				if (n <= 2) {
 					while (i < n) {
-						OPS_intval = __ASHL(OPS_intval, 4) + (int64)Ord__7(dig[i], 1);
+						OPS_intval = __ASHL(OPS_intval, 4) + Ord__7(dig[i], 1);
 						i += 1;
 					}
 				} else {
@@ -192,7 +192,7 @@ static void OPS_Number (void)
 						OPS_intval = -1;
 					}
 					while (i < n) {
-						OPS_intval = __ASHL(OPS_intval, 4) + (int64)Ord__7(dig[i], 1);
+						OPS_intval = __ASHL(OPS_intval, 4) + Ord__7(dig[i], 1);
 						i += 1;
 					}
 				} else {
@@ -203,8 +203,8 @@ static void OPS_Number (void)
 				while (i < n) {
 					d = Ord__7(dig[i], 0);
 					i += 1;
-					if (OPS_intval <= (int64)__DIV(9223372036854775807 - d, 10)) {
-						OPS_intval = OPS_intval * 10 + (int64)d;
+					if ((int64)OPS_intval <= __DIV(9223372036854775807 - (int64)d, 10)) {
+						OPS_intval = OPS_intval * 10 + d;
 					} else {
 						OPS_err(203);
 					}
diff --git a/bootstrap/unix-48/OPS.h b/bootstrap/unix-48/OPS.h
index af53d634..57cf06d3 100644
--- a/bootstrap/unix-48/OPS.h
+++ b/bootstrap/unix-48/OPS.h
@@ -15,7 +15,7 @@ typedef
 import OPS_Name OPS_name;
 import OPS_String OPS_str;
 import int16 OPS_numtyp;
-import int64 OPS_intval;
+import int32 OPS_intval;
 import REAL OPS_realval;
 import LONGREAL OPS_lrlval;
 
diff --git a/bootstrap/unix-48/OPT.c b/bootstrap/unix-48/OPT.c
index a12c1a7f..62ff8882 100644
--- a/bootstrap/unix-48/OPT.c
+++ b/bootstrap/unix-48/OPT.c
@@ -167,11 +167,14 @@ OPT_Struct OPT_IntType (int32 size)
 	OPT_Struct _o_result;
 	int16 i;
 	i = 1;
-	while ((OPT_IntTypes[__X(i, 20)]->size < size && OPT_IntTypes[__X(i + 1, 20)] != NIL)) {
+	while (i < 19) {
+		if ((OPT_IntTypes[__X(i, 20)] != NIL && OPT_IntTypes[__X(i, 20)]->size >= size)) {
+			_o_result = OPT_IntTypes[__X(i, 20)];
+			return _o_result;
+		}
 		i += 1;
 	}
-	_o_result = OPT_IntTypes[__X(i, 20)];
-	return _o_result;
+	__RETCHK;
 }
 
 OPT_Struct OPT_ShorterOrLongerType (OPT_Struct x, int16 dir)
diff --git a/bootstrap/unix-88/OPT.c b/bootstrap/unix-88/OPT.c
index 82c2df59..d9b211df 100644
--- a/bootstrap/unix-88/OPT.c
+++ b/bootstrap/unix-88/OPT.c
@@ -167,11 +167,14 @@ OPT_Struct OPT_IntType (int64 size)
 	OPT_Struct _o_result;
 	int32 i;
 	i = 1;
-	while ((OPT_IntTypes[__X(i, 20)]->size < size && OPT_IntTypes[__X(i + 1, 20)] != NIL)) {
+	while (i < 19) {
+		if ((OPT_IntTypes[__X(i, 20)] != NIL && OPT_IntTypes[__X(i, 20)]->size >= size)) {
+			_o_result = OPT_IntTypes[__X(i, 20)];
+			return _o_result;
+		}
 		i += 1;
 	}
-	_o_result = OPT_IntTypes[__X(i, 20)];
-	return _o_result;
+	__RETCHK;
 }
 
 OPT_Struct OPT_ShorterOrLongerType (OPT_Struct x, int32 dir)
diff --git a/bootstrap/windows-48/OPS.c b/bootstrap/windows-48/OPS.c
index 5243ea65..29ea2414 100644
--- a/bootstrap/windows-48/OPS.c
+++ b/bootstrap/windows-48/OPS.c
@@ -17,7 +17,7 @@ typedef
 export OPS_Name OPS_name;
 export OPS_String OPS_str;
 export int16 OPS_numtyp;
-export int64 OPS_intval;
+export int32 OPS_intval;
 export REAL OPS_realval;
 export LONGREAL OPS_lrlval;
 static CHAR OPS_ch;
@@ -178,7 +178,7 @@ static void OPS_Number (void)
 				OPS_numtyp = 1;
 				if (n <= 2) {
 					while (i < n) {
-						OPS_intval = __ASHL(OPS_intval, 4) + (int64)Ord__7(dig[i], 1);
+						OPS_intval = __ASHL(OPS_intval, 4) + Ord__7(dig[i], 1);
 						i += 1;
 					}
 				} else {
@@ -192,7 +192,7 @@ static void OPS_Number (void)
 						OPS_intval = -1;
 					}
 					while (i < n) {
-						OPS_intval = __ASHL(OPS_intval, 4) + (int64)Ord__7(dig[i], 1);
+						OPS_intval = __ASHL(OPS_intval, 4) + Ord__7(dig[i], 1);
 						i += 1;
 					}
 				} else {
@@ -203,8 +203,8 @@ static void OPS_Number (void)
 				while (i < n) {
 					d = Ord__7(dig[i], 0);
 					i += 1;
-					if (OPS_intval <= (int64)__DIV(9223372036854775807 - d, 10)) {
-						OPS_intval = OPS_intval * 10 + (int64)d;
+					if ((int64)OPS_intval <= __DIV(9223372036854775807 - (int64)d, 10)) {
+						OPS_intval = OPS_intval * 10 + d;
 					} else {
 						OPS_err(203);
 					}
diff --git a/bootstrap/windows-48/OPS.h b/bootstrap/windows-48/OPS.h
index af53d634..57cf06d3 100644
--- a/bootstrap/windows-48/OPS.h
+++ b/bootstrap/windows-48/OPS.h
@@ -15,7 +15,7 @@ typedef
 import OPS_Name OPS_name;
 import OPS_String OPS_str;
 import int16 OPS_numtyp;
-import int64 OPS_intval;
+import int32 OPS_intval;
 import REAL OPS_realval;
 import LONGREAL OPS_lrlval;
 
diff --git a/bootstrap/windows-48/OPT.c b/bootstrap/windows-48/OPT.c
index a12c1a7f..62ff8882 100644
--- a/bootstrap/windows-48/OPT.c
+++ b/bootstrap/windows-48/OPT.c
@@ -167,11 +167,14 @@ OPT_Struct OPT_IntType (int32 size)
 	OPT_Struct _o_result;
 	int16 i;
 	i = 1;
-	while ((OPT_IntTypes[__X(i, 20)]->size < size && OPT_IntTypes[__X(i + 1, 20)] != NIL)) {
+	while (i < 19) {
+		if ((OPT_IntTypes[__X(i, 20)] != NIL && OPT_IntTypes[__X(i, 20)]->size >= size)) {
+			_o_result = OPT_IntTypes[__X(i, 20)];
+			return _o_result;
+		}
 		i += 1;
 	}
-	_o_result = OPT_IntTypes[__X(i, 20)];
-	return _o_result;
+	__RETCHK;
 }
 
 OPT_Struct OPT_ShorterOrLongerType (OPT_Struct x, int16 dir)
diff --git a/bootstrap/windows-88/OPT.c b/bootstrap/windows-88/OPT.c
index 82c2df59..d9b211df 100644
--- a/bootstrap/windows-88/OPT.c
+++ b/bootstrap/windows-88/OPT.c
@@ -167,11 +167,14 @@ OPT_Struct OPT_IntType (int64 size)
 	OPT_Struct _o_result;
 	int32 i;
 	i = 1;
-	while ((OPT_IntTypes[__X(i, 20)]->size < size && OPT_IntTypes[__X(i + 1, 20)] != NIL)) {
+	while (i < 19) {
+		if ((OPT_IntTypes[__X(i, 20)] != NIL && OPT_IntTypes[__X(i, 20)]->size >= size)) {
+			_o_result = OPT_IntTypes[__X(i, 20)];
+			return _o_result;
+		}
 		i += 1;
 	}
-	_o_result = OPT_IntTypes[__X(i, 20)];
-	return _o_result;
+	__RETCHK;
 }
 
 OPT_Struct OPT_ShorterOrLongerType (OPT_Struct x, int32 dir)
diff --git a/src/compiler/OPS.Mod b/src/compiler/OPS.Mod
index 909cdee2..e386e538 100644
--- a/src/compiler/OPS.Mod
+++ b/src/compiler/OPS.Mod
@@ -52,7 +52,7 @@ MODULE OPS;  (* NW, RC 6.3.89 / 18.10.92 *)    (* object model 3.6.92 *)
     name*:    Name;
     str*:     String;
     numtyp*:  INTEGER;       (* 1 = char, 2 = integer, 3 = real, 4 = longreal *)
-    intval*:  SYSTEM.INT64;  (* integer value or string length *)
+    intval*:  LONGINT (* todo SYSTEM.INT64 *);  (* integer value or string length *)
     realval*: REAL;
     lrlval*:  LONGREAL;
 
diff --git a/src/compiler/OPT.Mod b/src/compiler/OPT.Mod
index 8b21b9a5..cd1eae8b 100644
--- a/src/compiler/OPT.Mod
+++ b/src/compiler/OPT.Mod
@@ -217,8 +217,10 @@ PROCEDURE IntType*(size: LONGINT): Struct;
 (* Selects smallest standard integer type for given size in bytes *)
   VAR i: INTEGER;
 BEGIN
-  i := 1; WHILE (IntTypes[i].size < size) & (IntTypes[i+1] # NIL) DO INC(i) END;
-  RETURN IntTypes[i];
+  i := 1; WHILE i < LEN(IntTypes) - 1 DO (* First and last entries are always NIL *)
+    IF (IntTypes[i] # NIL) & (IntTypes[i].size >= size) THEN RETURN IntTypes[i] END;
+    INC(i)
+  END;
 END IntType;
 
 PROCEDURE ShorterOrLongerType*(x: Struct; dir: INTEGER): Struct;