diff --git a/src/expr.c b/src/expr.c
index f45afb72..65060522 100644
--- a/src/expr.c
+++ b/src/expr.c
@@ -783,12 +783,11 @@ static int Add(void)
 
 /* If both are ints, just add 'em */
     if (v2.type == INT_TYPE && v1.type == INT_TYPE) {
-        int old = v1.v.val;
-	v1.v.val += v2.v.val;
         /* Check for overflow */
-        if (_private_add_overflow(v1.v.val, v2.v.val, old)) {
+        if (_private_add_overflow(v1.v.val, v2.v.val)) {
             return E_2HIGH;
         }
+	v1.v.val += v2.v.val;
 	PushValStack(v1);
 	return OK;
     }
@@ -796,9 +795,8 @@ static int Add(void)
 /* If it's a date plus an int, add 'em */
     if ((v1.type == DATE_TYPE && v2.type == INT_TYPE) ||
 	(v1.type == INT_TYPE && v2.type == DATE_TYPE)) {
-        int old = v1.v.val;
+        if (_private_add_overflow(v1.v.val, v2.v.val)) return E_DATE_OVER;
 	v1.v.val += v2.v.val;
-        if (_private_add_overflow(v1.v.val, v2.v.val, old)) return E_DATE_OVER;
 	if (v1.v.val < 0) return E_DATE_OVER;
 	v1.type = DATE_TYPE;
 	PushValStack(v1);
@@ -808,9 +806,8 @@ static int Add(void)
 /* If it's a datetime plus an int or a time, add 'em */
     if ((v1.type == DATETIME_TYPE && (v2.type == INT_TYPE || v2.type == TIME_TYPE)) ||
 	((v1.type == INT_TYPE || v1.type == TIME_TYPE) && v2.type == DATETIME_TYPE)) {
-        int old = v1.v.val;
+        if (_private_add_overflow(v1.v.val, v2.v.val)) return E_DATE_OVER;
 	v1.v.val += v2.v.val;
-        if (_private_add_overflow(v1.v.val, v2.v.val, old)) return E_DATE_OVER;
 	if (v1.v.val < 0) return E_DATE_OVER;
 	v1.type = DATETIME_TYPE;
 	PushValStack(v1);
@@ -822,9 +819,8 @@ static int Add(void)
     if ((v1.type == TIME_TYPE && v2.type == INT_TYPE) ||
 	(v1.type == INT_TYPE && v2.type == TIME_TYPE) ||
 	(v1.type == TIME_TYPE && v2.type == TIME_TYPE)) {
-        int old = v1.v.val;
+        if (_private_add_overflow(v1.v.val, v2.v.val)) return E_DATE_OVER;
 	v1.v.val += v2.v.val;
-        if (_private_add_overflow(v1.v.val, v2.v.val, old)) return E_DATE_OVER;
 	v1.v.val = v1.v.val % MINUTES_PER_DAY;
 	if (v1.v.val < 0) v1.v.val += MINUTES_PER_DAY;
 	v1.type = TIME_TYPE;
@@ -885,18 +881,16 @@ static int Subtract(void)
 
     /* If they're both INTs, do subtraction */
     if (v1.type == INT_TYPE && v2.type == INT_TYPE) {
-        int old = v1.v.val;
+        if (_private_sub_overflow(v1.v.val, v2.v.val)) return E_2HIGH;
 	v1.v.val -= v2.v.val;
-        if (_private_sub_overflow(v1.v.val, v2.v.val, old)) return E_2HIGH;
 	PushValStack(v1);
 	return OK;
     }
 
     /* If it's a date minus an int, do subtraction, checking for underflow */
     if (v1.type == DATE_TYPE && v2.type == INT_TYPE) {
-        int old = v1.v.val;
+        if (_private_sub_overflow(v1.v.val, v2.v.val)) return E_DATE_OVER;
 	v1.v.val -= v2.v.val;
-        if (_private_sub_overflow(v1.v.val, v2.v.val, old)) return E_DATE_OVER;
 	if (v1.v.val < 0) return E_DATE_OVER;
 	PushValStack(v1);
 	return OK;
@@ -905,9 +899,8 @@ static int Subtract(void)
     /* If it's a datetime minus an int or a time, do subtraction,
      * checking for underflow */
     if (v1.type == DATETIME_TYPE && (v2.type == INT_TYPE || v2.type == TIME_TYPE)) {
-        int old = v1.v.val;
+        if (_private_sub_overflow(v1.v.val, v2.v.val)) return E_DATE_OVER;
 	v1.v.val -= v2.v.val;
-        if (_private_sub_overflow(v1.v.val, v2.v.val, old)) return E_DATE_OVER;
 	if (v1.v.val < 0) return E_DATE_OVER;
 	PushValStack(v1);
 	return OK;
@@ -925,9 +918,8 @@ static int Subtract(void)
     if ((v1.type == TIME_TYPE && v2.type == TIME_TYPE) ||
 	(v1.type == DATETIME_TYPE && v2.type == DATETIME_TYPE) ||
 	(v1.type == DATE_TYPE && v2.type == DATE_TYPE)) {
-        int old = v1.v.val;
+        if (_private_sub_overflow(v1.v.val, v2.v.val)) return E_DATE_OVER;
 	v1.v.val -= v2.v.val;
-        if (_private_sub_overflow(v1.v.val, v2.v.val, old)) return E_DATE_OVER;
 	v1.type = INT_TYPE;
 	PushValStack(v1);
 	return OK;
@@ -962,11 +954,8 @@ static int Multiply(void)
             (v1.v.val == -1 && v2.v.val == INT_MIN)) {
             return E_2HIGH;
         }
-        int old = v1.v.val;
+        if (_private_mul_overflow(v1.v.val, v2.v.val)) return E_2HIGH;
 	v1.v.val *= v2.v.val;
-        if (v2.v.val != 0) {
-            if (_private_div(v1.v.val, v2.v.val) != old) return E_2HIGH;
-        }
 	PushValStack(v1);
 	return OK;
     }
@@ -1177,9 +1166,8 @@ static int UnMinus(void)
 {
     Value *v = &ValStack[ValStackPtr-1];
     if (v->type != INT_TYPE) return E_BAD_TYPE;
-    int old = v->v.val;
+    if (v->v.val == INT_MIN) return E_2HIGH;
     v->v.val = -v->v.val;
-    if (_private_unminus_overflow(old, v->v.val)) return E_2HIGH;
     return OK;
 }
 
diff --git a/src/expr.h b/src/expr.h
index 68b6d8ee..c9c5be9d 100644
--- a/src/expr.h
+++ b/src/expr.h
@@ -58,7 +58,7 @@ else \
    in various arithmetic operators.  They have to be in separate
    functions with extern linkage to defeat compiler optimizations
    that would otherwise break the overflow checks. */
-extern int _private_div(int a, int b);
-extern int _private_add_overflow(int result, int b, int old);
-extern int _private_sub_overflow(int result, int b, int old);
-extern int _private_unminus_overflow(int a, int b);
+extern int _private_mul_overflow(int a, int b);
+extern int _private_add_overflow(int a, int b);
+extern int _private_sub_overflow(int a, int b);
+
diff --git a/src/utils.c b/src/utils.c
index d9a2eae8..39f70381 100644
--- a/src/utils.c
+++ b/src/utils.c
@@ -130,24 +130,33 @@ int DateOK(int y, int m, int d)
 
 /* Functions designed to defeat gcc optimizer */
 
-int _private_div(int a, int b) { return a/b; }
-int _private_add_overflow(int result, int b, int old)
+int _private_mul_overflow(int a, int b)
 {
-    if (b > 0 && result < old) return 1;
-    if (b < 0 && result > old) return 1;
-    return 0;
-}
-int _private_sub_overflow(int result, int b, int old)
-{
-    if (b < 0 && result < old) return 1;
-    if (b > 0 && result > old) return 1;
+    double aa = (double) a;
+    double bb = (double) b;
+
+    if (aa*bb > (double) INT_MAX || aa*bb < (double) INT_MIN) {
+        return 1;
+    }
     return 0;
 }
 
-int _private_unminus_overflow(int a, int b)
+int _private_add_overflow(int a, int b)
 {
-    if (a > 0 && b > 0) return 1;
-    if (a < 0 && b < 0) return 1;
+    double aa = (double) a;
+    double bb = (double) b;
+
+    if (aa+bb < (double) INT_MIN) return 1;
+    if (aa+bb > (double) INT_MAX) return 1;
+    return 0;
+}
+int _private_sub_overflow(int a, int b)
+{
+    double aa = (double) a;
+    double bb = (double) b;
+
+    if (aa-bb < (double) INT_MIN) return 1;
+    if (aa-bb > (double) INT_MAX) return 1;
     return 0;
 }