diff --git a/libs/libxx/libcxxmini/libxx_new.cxx b/libs/libxx/libcxxmini/libxx_new.cxx
index 16aacd16bc..997ab87ea2 100644
--- a/libs/libxx/libcxxmini/libxx_new.cxx
+++ b/libs/libxx/libcxxmini/libxx_new.cxx
@@ -69,7 +69,7 @@ FAR void *operator new(std::size_t nbytes)
     }
 #endif
 
-  DEBUGASSERT(alloc != nullptr);
+  DEBUGASSERT(alloc != NULL);
 
   // Return the allocated value
 
@@ -78,7 +78,7 @@ FAR void *operator new(std::size_t nbytes)
 
 FAR void *operator new(std::size_t nbytes, FAR void *ptr)
 {
-  DEBUGASSERT(ptr != nullptr);
+  DEBUGASSERT(ptr != NULL);
 
   // Return the ptr pointer
 
diff --git a/libs/libxx/libcxxmini/libxx_newa.cxx b/libs/libxx/libcxxmini/libxx_newa.cxx
index f2974534a5..f0d3eb07d5 100644
--- a/libs/libxx/libcxxmini/libxx_newa.cxx
+++ b/libs/libxx/libcxxmini/libxx_newa.cxx
@@ -77,7 +77,7 @@ FAR void *operator new[](std::size_t nbytes)
     }
 #endif
 
-  DEBUGASSERT(alloc != nullptr);
+  DEBUGASSERT(alloc != NULL);
 
   // Return the allocated value
 
@@ -86,7 +86,7 @@ FAR void *operator new[](std::size_t nbytes)
 
 FAR void *operator new[](std::size_t nbytes, FAR void *ptr)
 {
-  DEBUGASSERT(ptr != nullptr);
+  DEBUGASSERT(ptr != NULL);
 
   // Return the ptr pointer