From 07876e443372adba0321be0dc1ba3e61ce93dd15 Mon Sep 17 00:00:00 2001
From: Christopher Blaesius <christopher.blaesius@krumedia.com>
Date: Tue, 6 Mar 2018 12:24:40 +0100
Subject: [PATCH] Character classification functions (isspace, isalnum) are
 undefined for signed chars

Convert them to int using char_traits or static_cast to unsigned char
---
 include/date/date.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/date/date.h b/include/date/date.h
index 8d3f43c..e610315 100644
--- a/include/date/date.h
+++ b/include/date/date.h
@@ -7180,7 +7180,7 @@ from_stream(std::basic_istream<CharT, Traits>& is, const CharT* fmt,
                 }
                 else  // !command
                 {
-                    if (isspace(*fmt))
+                    if (isspace(static_cast<unsigned char>(*fmt)))
                         ws(is); // space matches 0 or more white space characters
                     else
                         read(is, *fmt);