diff --git a/pw_minimal_cpp_stdlib/isolated_test.cc b/pw_minimal_cpp_stdlib/isolated_test.cc
index 4f90a82..1be9662 100644
--- a/pw_minimal_cpp_stdlib/isolated_test.cc
+++ b/pw_minimal_cpp_stdlib/isolated_test.cc
@@ -252,7 +252,7 @@
 }
 
 TEST(New, PlacementNew) {
-  unsigned char value[4];
+  alignas(sizeof(int)) unsigned char value[sizeof(int)];
   new (value) int(1234);
 
   int int_value;