diff --git a/src/librustc_trans/cabi_sparc64.rs b/src/librustc_trans/cabi_sparc64.rs
index 6c5d325419148..8d56086528744 100644
--- a/src/librustc_trans/cabi_sparc64.rs
+++ b/src/librustc_trans/cabi_sparc64.rs
@@ -24,7 +24,7 @@ fn is_homogeneous_aggregate<'a, 'tcx>(cx: &CodegenCx<'a, 'tcx>, arg: &mut ArgTyp
         let valid_unit = match unit.kind {
             RegKind::Integer => false,
             RegKind::Float => true,
-            RegKind::Vector => arg.layout.size.bits() == 256
+            RegKind::Vector => arg.layout.size.bits() == 128
         };
 
         if valid_unit {