diff --git a/include/boost/charconv/from_chars.hpp b/include/boost/charconv/from_chars.hpp
index a742847..4fe1f93 100644
--- a/include/boost/charconv/from_chars.hpp
+++ b/include/boost/charconv/from_chars.hpp
@@ -45,8 +45,8 @@ struct from_chars_result
 
 namespace detail {
 
-static constexpr std::array<unsigned char, 256> uchar_values =
-    {{255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
+static constexpr unsigned char uchar_values[] =
+     {255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
       255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
       255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
         0,   1,   2,   3,   4,   5,   6,   7,   8,   9, 255, 255, 255, 255, 255, 255,
@@ -61,7 +61,7 @@ static constexpr std::array<unsigned char, 256> uchar_values =
       255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
       255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
       255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
-      255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}};
+      255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255};
 
 // Convert characters for 0-9, A-Z, a-z to 0-35. Anything else is 255
 constexpr unsigned char digit_from_char(char val) noexcept