diff --git a/vlib/crypto/ed25519/internal/edwards25519/extra.v b/vlib/crypto/ed25519/internal/edwards25519/extra.v
index c6dd6a4dad..4935675df4 100644
--- a/vlib/crypto/ed25519/internal/edwards25519/extra.v
+++ b/vlib/crypto/ed25519/internal/edwards25519/extra.v
@@ -33,7 +33,7 @@ fn (mut s Scalar) pow2k(k int) {
 // If the coordinates are invalid or don't represent a valid point on the curve,
 // set_extended_coordinates returns an error and the receiver is
 // unchanged. Otherwise, set_extended_coordinates returns v.
-fn (mut v Point) set_extended_coordinates(x Element, y Element, z Element, t Element) ?Point {
+fn (mut v Point) set_extended_coordinates(x Element, y Element, z Element, t Element) !Point {
 	if !is_on_curve(x, y, z, t) {
 		return error('edwards25519: invalid point coordinates')
 	}
diff --git a/vlib/math/unsigned/uint128.v b/vlib/math/unsigned/uint128.v
index b08852feba..99b841de15 100644
--- a/vlib/math/unsigned/uint128.v
+++ b/vlib/math/unsigned/uint128.v
@@ -417,7 +417,7 @@ pub fn uint128_new(lo u64, hi u64) Uint128 {
 	return Uint128{lo, hi}
 }
 
-pub fn uint128_from_dec_str(value string) ?Uint128 {
+pub fn uint128_from_dec_str(value string) !Uint128 {
 	mut res := unsigned.uint128_zero
 	for b_ in value.bytes() {
 		b := b_ - '0'.bytes()[0]