reverse condition in uN::checked_sub

ivan-shrimp · ivan-shrimp · commit 7fde7308bf75 · 2024-05-12T11:29:24.000+08:00
diff --git a/library/core/src/num/uint_macros.rs b/library/core/src/num/uint_macros.rs
@@ -584,11 +584,11 @@ macro_rules! uint_impl {
             // Thus, rather than using `overflowing_sub` that produces a wrapping
             // subtraction, check it ourself so we can use an unchecked one.
 
-            if self >= rhs {
+            if self < rhs {
+                None
+            } else {
                 // SAFETY: just checked this can't overflow
                 Some(unsafe { intrinsics::unchecked_sub(self, rhs) })
-            } else {
-                None
             }
         }
 

Original file line number	Diff line number	Diff line change
`@@ -584,11 +584,11 @@ macro_rules! uint_impl {`
`584`	`584`	// Thus, rather than using `overflowing_sub` that produces a wrapping
`585`	`585`	`// subtraction, check it ourself so we can use an unchecked one.`
`586`	`586`
`587`		`- if self >= rhs {`
	`587`	`+ if self < rhs {`
	`588`	`+ None`
	`589`	`+ } else {`
`588`	`590`	`// SAFETY: just checked this can't overflow`
`589`	`591`	`Some(unsafe { intrinsics::unchecked_sub(self, rhs) })`
`590`		`- } else {`
`591`		`- None`
`592`	`592`	`}`
`593`	`593`	`}`
`594`	`594`