fix(integer): fix StaticUnsignedBigInt cast into u128

mayeul-zama · mayeul-zama · commit d0cc3f6e23ac · 2025-11-17T15:41:46.000+01:00
diff --git a/tfhe/src/integer/bigint/static_unsigned.rs b/tfhe/src/integer/bigint/static_unsigned.rs
@@ -418,7 +418,7 @@ impl<const N: usize> CastFrom<u128> for StaticUnsignedBigInt<N> {
 
 impl<const N: usize> CastFrom<StaticUnsignedBigInt<N>> for u128 {
     fn cast_from(input: StaticUnsignedBigInt<N>) -> Self {
-        input.0[0] as Self | input.0.get(1).copied().unwrap_or(0) as Self
+        input.0[0] as Self | ((input.0.get(1).copied().unwrap_or(0) as Self) << 64)
     }
 }
 

Original file line number	Diff line number	Diff line change
`@@ -418,7 +418,7 @@ impl<const N: usize> CastFrom<u128> for StaticUnsignedBigInt<N> {`
`418`	`418`
`419`	`419`	`impl<const N: usize> CastFrom<StaticUnsignedBigInt<N>> for u128 {`
`420`	`420`	`fn cast_from(input: StaticUnsignedBigInt<N>) -> Self {`
`421`		`- input.0[0] as Self \| input.0.get(1).copied().unwrap_or(0) as Self`
	`421`	`+ input.0[0] as Self \| ((input.0.get(1).copied().unwrap_or(0) as Self) << 64)`
`422`	`422`	`}`
`423`	`423`	`}`
`424`	`424`