diff --git a/src/ir/type_bridge.zig b/src/ir/type_bridge.zig
index dfbea28..64e4531 100644
--- a/src/ir/type_bridge.zig
+++ b/src/ir/type_bridge.zig
@@ -79,14 +79,16 @@ pub fn bridgeType(ty: sx_types.Type, table: *TypeTable) TypeId {
             16 => .s16,
             32 => .s32,
             64 => .s64,
-            else => .s64,
+            // Non-standard width: intern the exact width rather than quantising
+            // to s64 (which would silently change the type's size).
+            else => table.intern(.{ .signed = w }),
         },
         .unsigned => |w| switch (w) {
             8 => .u8,
             16 => .u16,
             32 => .u32,
             64 => .u64,
-            else => .u64,
+            else => table.intern(.{ .unsigned = w }),
         },
         .f32 => .f32,
         .f64 => .f64,