--- gcc/cp/call.c

+++ gcc/cp/call.c

@@ -6904,7 +6904,7 @@ convert_like_real (conversion *convs, tree expr, tree fn, int argnum,

 	elttype = cp_build_qualified_type

 	  (elttype, cp_type_quals (elttype) | TYPE_QUAL_CONST);

 	array = build_array_of_n_type (elttype, len);

-	array = finish_compound_literal (array, new_ctor, complain, fcl_c99);

+	array = finish_compound_literal (array, new_ctor, complain);

 	/* Take the address explicitly rather than via decay_conversion

 	   to avoid the error about taking the address of a temporary.  */

 	array = cp_build_addr_expr (array, complain);

@@ -10984,13 +10984,11 @@ set_up_extended_ref_temp (tree decl, tree expr, vec<tree, va_gc> **cleanups,

 	     lvalue-rvalue conversion applied to "a glvalue of literal type

 	     that refers to a non-volatile temporary object initialized

 	     with a constant expression".  Rather than try to communicate

-	     that this VAR_DECL is a temporary, just mark it constexpr.

-

-	     Currently this is only useful for initializer_list temporaries,

-	     since reference vars can't appear in constant expressions.  */

+	     that this VAR_DECL is a temporary, just mark it constexpr.  */

 	  DECL_DECLARED_CONSTEXPR_P (var) = true;

 	  DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (var) = true;

 	  TREE_CONSTANT (var) = true;

+	  TREE_READONLY (var) = true;

 	}

       DECL_INITIAL (var) = init;

       init = NULL_TREE;

--- gcc/cp/tree.c

+++ gcc/cp/tree.c

@@ -442,6 +442,14 @@ build_target_expr (tree decl, tree value, tsubst_flags_t complain)

 		       || useless_type_conversion_p (TREE_TYPE (decl),

 						     TREE_TYPE (value)));

+  /* Set TREE_READONLY for optimization, such as gimplify_init_constructor

+     moving a constant aggregate into .rodata.  */

+  if (CP_TYPE_CONST_NON_VOLATILE_P (type)

+      && !TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)

+      && !VOID_TYPE_P (TREE_TYPE (value))

+      && reduced_constant_expression_p (value))

+    TREE_READONLY (decl) = true;

+

   if (complain & tf_no_cleanup)

     /* The caller is building a new-expr and does not need a cleanup.  */

     t = NULL_TREE;

--- /dev/null

+++ gcc/testsuite/g++.dg/cpp1y/pr95226.C

@@ -0,0 +1,17 @@

+// PR c++/95226

+// { dg-do run { target c++14 } }

+

+#include <vector>

+

+struct T {

+  unsigned a;

+  float b {8.};

+};

+

+int main()

+{

+  T t = {1};

+  std::vector<T> tt = {{1}, {2}};

+  if (t.a != 1 || t.b != 8.0f || tt[0].a != 1 || tt[0].b != 8.0f || tt[1].a != 2 || tt[1].b != 8.0f)

+    __builtin_abort ();

+}