diff --git a/include/boost/hash2/sha2.hpp b/include/boost/hash2/sha2.hpp
index 31e06e9..98493ed 100644
--- a/include/boost/hash2/sha2.hpp
+++ b/include/boost/hash2/sha2.hpp
@@ -37,13 +37,11 @@ struct sha2_base
     static constexpr int N = M;
 
     unsigned char buffer_[ N ] = {};
-    std::size_t m_; // == n_ % N
+    std::size_t m_ = 0; // == n_ % N
 
-    std::uint64_t n_;
+    std::uint64_t n_ = 0;
 
-    BOOST_CXX14_CONSTEXPR sha2_base(): m_( 0 ), n_( 0 )
-    {
-    }
+    constexpr sha2_base() = default;
 
     void update( void const* pv, std::size_t n )
     {
@@ -540,7 +538,6 @@ class sha2_512 : detail::sha2_512_base
         }
     }
 
-
     BOOST_CXX14_CONSTEXPR result_type result()
     {
         unsigned char bits[ 16 ] = { 0 };
diff --git a/test/Jamfile b/test/Jamfile
index 6f49514..166a3b3 100644
--- a/test/Jamfile
+++ b/test/Jamfile
@@ -124,6 +124,7 @@ run sha1_cx_2.cpp ;
 run sha2.cpp ;
 run hmac_sha2.cpp ;
 run sha2_cx.cpp ;
+run sha2_cx_2.cpp ;
 
 run ripemd.cpp ;
 run hmac_ripemd.cpp ;
diff --git a/test/sha2_cx_2.cpp b/test/sha2_cx_2.cpp
new file mode 100644
index 0000000..d69101b
--- /dev/null
+++ b/test/sha2_cx_2.cpp
@@ -0,0 +1,83 @@
+// Copyright 2024 Christian Mazakas
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/hash2/sha2.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <boost/config.hpp>
+#include <array>
+
+#if defined(BOOST_MSVC) && BOOST_MSVC < 1920
+# pragma warning(disable: 4307) // integral constant overflow
+#endif
+
+#define STATIC_ASSERT(...) static_assert(__VA_ARGS__, #__VA_ARGS__)
+
+#if defined(BOOST_NO_CXX14_CONSTEXPR)
+
+# define TEST_EQ(x1, x2) BOOST_TEST_EQ(x1, x2)
+
+#else
+
+# define TEST_EQ(x1, x2) BOOST_TEST_EQ(x1, x2); STATIC_ASSERT(x1 == x2)
+
+#endif
+
+BOOST_CXX14_CONSTEXPR unsigned char to_byte( char c )
+{
+    if (c >= '0' && c <= '9') return c - '0';
+    if (c >= 'a' && c <= 'f') return c - 'a' + 10;
+    if (c >= 'A' && c <= 'F') return c - 'A' + 10;
+    return 0xff;
+}
+
+template<std::size_t N, std::size_t M = ( N - 1 ) / 2>
+BOOST_CXX14_CONSTEXPR boost::hash2::digest<M> digest_from_hex( char const (&str)[ N ] )
+{
+    boost::hash2::digest<M> dgst = {};
+    auto* p = dgst.data();
+    for( unsigned i = 0; i < M; ++i ) {
+        auto c1 = to_byte( str[ 2 * i ] );
+        auto c2 = to_byte( str[ 2 * i + 1 ] );
+        p[ i ] = ( c1 << 4 ) | c2;
+    }
+    return dgst;
+}
+
+int main()
+{
+    using namespace boost::hash2;
+
+    BOOST_CXX14_CONSTEXPR digest<32> r1 = digest_from_hex( "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855" );
+    BOOST_CXX14_CONSTEXPR digest<28> r2 = digest_from_hex( "d14a028c2a3a2bc9476102bb288234c415a2b01f828ea62ac5b3e42f" );
+    BOOST_CXX14_CONSTEXPR digest<64> r3 = digest_from_hex( "cf83e1357eefb8bdf1542850d66d8007d620e4050b5715dc83f4a921d36ce9ce47d0d13c5d85f2b0ff8318d2877eec2f63b931bd47417a81a538327af927da3e" );
+    BOOST_CXX14_CONSTEXPR digest<48> r4 = digest_from_hex( "38b060a751ac96384cd9327eb1b1e36a21fdb71114be07434c0cc7bf63f6e1da274edebfe76f65fbd51ad2f14898b95b" );
+    BOOST_CXX14_CONSTEXPR digest<28> r5 = digest_from_hex( "6ed0dd02806fa89e25de060c19d3ac86cabb87d6a0ddd05c333b84f4" );
+    BOOST_CXX14_CONSTEXPR digest<32> r6 = digest_from_hex( "c672b8d1ef56ed28ab87c3622c5114069bdd3ad7b8f9737498d0c01ecef0967a" );
+
+    TEST_EQ( sha2_256().result(), r1 );
+    TEST_EQ( sha2_256(0).result(), r1 );
+    TEST_EQ( sha2_256(nullptr, 0).result(), r1 );
+
+    TEST_EQ( sha2_224().result(), r2 );
+    TEST_EQ( sha2_224(0).result(), r2 );
+    TEST_EQ( sha2_224(nullptr, 0).result(), r2 );
+
+    TEST_EQ( sha2_512().result(), r3 );
+    TEST_EQ( sha2_512(0).result(), r3 );
+    TEST_EQ( sha2_512(nullptr, 0).result(), r3 );
+
+    TEST_EQ( sha2_384().result(), r4 );
+    TEST_EQ( sha2_384(0).result(), r4 );
+    TEST_EQ( sha2_384(nullptr, 0).result(), r4 );
+
+    TEST_EQ( sha2_512_224().result(), r5 );
+    TEST_EQ( sha2_512_224(0).result(), r5 );
+    TEST_EQ( sha2_512_224(nullptr, 0).result(), r5 );
+
+    TEST_EQ( sha2_512_256().result(), r6 );
+    TEST_EQ( sha2_512_256(0).result(), r6 );
+    TEST_EQ( sha2_512_256(nullptr, 0).result(), r6 );
+
+    return boost::report_errors();
+}