diff --git a/gcc/fold-const.cc b/gcc/fold-const.cc
index 8960e5289c0..7b268964acc 100644
--- a/gcc/fold-const.cc
+++ b/gcc/fold-const.cc
@@ -8601,6 +8601,8 @@ native_encode_initializer (tree init, unsigned char *ptr, int len,
 		  if (BYTES_BIG_ENDIAN != WORDS_BIG_ENDIAN)
 		    return 0;
 
+		  if (TREE_CODE (val) == NON_LVALUE_EXPR)
+		    val = TREE_OPERAND (val, 0);
 		  if (TREE_CODE (val) != INTEGER_CST)
 		    return 0;
 
diff --git a/gcc/testsuite/g++.dg/cpp2a/bit-cast16.C b/gcc/testsuite/g++.dg/cpp2a/bit-cast16.C
new file mode 100644
index 00000000000..d298af67ef2
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp2a/bit-cast16.C
@@ -0,0 +1,16 @@
+// PR c++/114537
+// { dg-do compile { target c++20 } }
+
+namespace std {
+template<typename T, typename F>
+constexpr T
+bit_cast (const F& f) noexcept
+{
+  return __builtin_bit_cast (T, f);
+}
+}
+
+struct A { signed char b : 1 = 0; signed char c : 7 = 0; };
+struct D { unsigned char e; };
+constexpr unsigned char f = std::bit_cast<D> (A{}).e;
+static_assert (f == 0);