diff --git a/indra/llmath/tests/alignment_test.cpp b/indra/llmath/tests/alignment_test.cpp
index ac0c45ae6f828d535dfdc791e9560274665bab6e..5c426c57c35c26c9c7457c9693701778b72a9c78 100644
--- a/indra/llmath/tests/alignment_test.cpp
+++ b/indra/llmath/tests/alignment_test.cpp
@@ -78,7 +78,7 @@ void alignment_test_object_t::test<1>()
 		align_ptr = ll_aligned_malloc_16(sizeof(MyVector4a));
 		ensure("ll_aligned_malloc_16 failed", is_aligned(align_ptr,16));
 
-		align_ptr = ll_aligned_realloc_16(align_ptr,2*sizeof(MyVector4a));
+		align_ptr = ll_aligned_realloc_16(align_ptr,2*sizeof(MyVector4a), sizeof(MyVector4a));
 		ensure("ll_aligned_realloc_16 failed", is_aligned(align_ptr,16));
 
 		ll_aligned_free_16(align_ptr);