diff --git a/core/intrinsics/intrinsics.odin b/core/intrinsics/intrinsics.odin
index afa0efa36..c23cbd473 100644
--- a/core/intrinsics/intrinsics.odin
+++ b/core/intrinsics/intrinsics.odin
@@ -165,7 +165,7 @@ type_is_specialization_of :: proc($T, $S: typeid) -> bool ---
 
 type_is_variant_of :: proc($U, $V: typeid) -> bool where type_is_union(U) ---
 type_union_tag_type :: proc($T: typeid) -> typeid where type_is_union(T) ---
-type_union_tag_offset :: proc($T: typeid) -> int where type_is_union(T) ---
+type_union_tag_offset :: proc($T: typeid) -> uintptr where type_is_union(T) ---
 type_union_base_tag_value :: proc($T: typeid) -> int where type_is_union(U) ---
 type_union_variant_count :: proc($T: typeid) -> int where type_is_union(T) ---
 type_variant_type_of :: proc($T: typeid, $index: int) -> typeid where type_is_union(T) ---