From 7c8ad32ff97348c5ea93df308cc32c3262357747 Mon Sep 17 00:00:00 2001
From: Krystian Stasiowski <sdkrystian@gmail.com>
Date: Mon, 16 Dec 2019 19:22:41 -0500
Subject: [PATCH] A object pointer value is only a constant expression if it
 points to an object with static storage duration.

---
 .../static_string/detail/static_string.hpp    |  8 +++----
 test/static_string.cpp                        | 21 +++++++++++++++----
 2 files changed, 21 insertions(+), 8 deletions(-)

diff --git a/include/boost/static_string/detail/static_string.hpp b/include/boost/static_string/detail/static_string.hpp
index ec46d6d..5032c40 100644
--- a/include/boost/static_string/detail/static_string.hpp
+++ b/include/boost/static_string/detail/static_string.hpp
@@ -76,14 +76,14 @@ public:
   CharT*
   data_impl() noexcept
   {
-    return +data_;
+    return data_;
   }
 
   BOOST_STATIC_STRING_CPP14_CONSTEXPR
   CharT const*
   data_impl() const noexcept
   {
-    return +data_;
+    return data_;
   }
 
   BOOST_STATIC_STRING_CPP11_CONSTEXPR
@@ -171,14 +171,14 @@ public:
   CharT*
   data_impl() noexcept
   {
-    return +data_;
+    return data_;
   }
 
   BOOST_STATIC_STRING_CPP14_CONSTEXPR
   CharT const*
   data_impl() const noexcept
   {
-    return +data_;
+    return data_;
   }
 
   BOOST_STATIC_STRING_CPP11_CONSTEXPR
diff --git a/test/static_string.cpp b/test/static_string.cpp
index 64ab6bd..180be03 100644
--- a/test/static_string.cpp
+++ b/test/static_string.cpp
@@ -6932,6 +6932,23 @@ constexpr bool testConstexpr()
 #elif __cplusplus >= 201703L
   // c++17 constexpr tests
 
+  using S = basic_static_string<16, char, cxper_char_traits>;
+  // ctor
+  {
+    constexpr S s1;
+    constexpr S s2(1, 'a');
+    constexpr S s3("");
+    constexpr S s4("", 1);
+    constexpr S s5 = s1;
+    constexpr auto b = s1.size();
+    constexpr auto c = s1.empty();
+    constexpr auto d = s1.max_size();
+    constexpr auto e = s1.capacity();
+    constexpr auto f = s1.length();
+    constexpr auto g = s2.front();
+    constexpr auto h = s2.back();
+  }
+
 #elif __cplusplus >= 201402L
   // c++14 constexpr tests
   
@@ -6951,10 +6968,6 @@ constexpr bool testConstexpr()
     constexpr auto f = s1.length();
     constexpr auto g = s2.front();
     constexpr auto h = s2.back();
-    constexpr auto k = s2.begin();
-    constexpr auto l = s2.end();
-    constexpr auto i = s2.data();
-    constexpr auto j = s2.c_str();
   }
 
   //constexpr auto g = s1.assign(1, '1');