diff --git a/gcc/cp/constexpr.cc b/gcc/cp/constexpr.cc
index 630c2190a8e..9b36f7628f3 100644
--- a/gcc/cp/constexpr.cc
+++ b/gcc/cp/constexpr.cc
@@ -3123,10 +3123,16 @@ cxx_eval_call_expression (const constexpr_ctx *ctx, tree t,
 	 At this point it has already been evaluated in the call
 	 to cxx_bind_parameters_in_call.  */
       new_obj = TREE_VEC_ELT (new_call.bindings, 0);
-      new_obj = cxx_fold_indirect_ref (ctx, loc, DECL_CONTEXT (fun), new_obj);
-
-      if (ctx->call && ctx->call->fundef
-	  && DECL_CONSTRUCTOR_P (ctx->call->fundef->decl))
+      bool empty_base = false;
+      new_obj = cxx_fold_indirect_ref (ctx, loc, DECL_CONTEXT (fun), new_obj,
+				       &empty_base);
+      /* If we're initializing an empty class, don't set constness, because
+	 cxx_fold_indirect_ref will return the wrong object to set constness
+	 of.  */
+      if (empty_base)
+	new_obj = NULL_TREE;
+      else if (ctx->call && ctx->call->fundef
+	       && DECL_CONSTRUCTOR_P (ctx->call->fundef->decl))
 	{
 	  tree cur_obj = TREE_VEC_ELT (ctx->call->bindings, 0);
 	  STRIP_NOPS (cur_obj);
diff --git a/gcc/testsuite/g++.dg/cpp2a/constexpr-init23.C b/gcc/testsuite/g++.dg/cpp2a/constexpr-init23.C
new file mode 100644
index 00000000000..466236d446d
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp2a/constexpr-init23.C
@@ -0,0 +1,22 @@
+// PR c++/115900
+// { dg-do compile { target c++20 } }
+
+struct A {
+    char m;
+    constexpr A() { m = 0; }
+};
+
+struct C {
+  constexpr C(){ };
+};
+
+struct B : C {
+  A a;
+  constexpr B() {}
+};
+
+struct D : B { };
+
+static constexpr A a;
+static constexpr B b;
+static constexpr D d;