diff --git a/gcc/alloc-pool.h b/gcc/alloc-pool.h
index 1785df5..4b4bc56 100644
--- a/gcc/alloc-pool.h
+++ b/gcc/alloc-pool.h
@@ -413,7 +413,8 @@ pool_allocator<T>::allocate ()
   VALGRIND_DISCARD (VALGRIND_MAKE_MEM_UNDEFINED (header, size));
 
   /* Call default constructor.  */
-  return (T *)(header);
+  char *ptr = (char *) header;
+  return new (ptr) T ();
 }
 
 /* Puts PTR back on POOL's free list.  */
diff --git a/gcc/cselib.h b/gcc/cselib.h
index cdd06ad..a0da27f 100644
--- a/gcc/cselib.h
+++ b/gcc/cselib.h
@@ -42,6 +42,9 @@ struct cselib_val
 
   struct cselib_val *next_containing_mem;
 
+  /* Default constructor.  */
+  cselib_val () {}
+
   /* Pool allocation new operator.  */
   inline void *operator new (size_t)
   {
@@ -67,6 +70,9 @@ struct elt_loc_list {
   /* The insn that made the equivalence.  */
   rtx_insn *setting_insn;
 
+  /* Default constructor.  */
+  elt_loc_list () {}
+
   /* Pool allocation new operator.  */
   inline void *operator new (size_t)
   {