From 5f5e70e96eaf8a0c3c74aaf4c5bbe39fe7f3dea1 Mon Sep 17 00:00:00 2001
From: Kevin Slattery <kslattery@shottracker.com>
Date: Wed, 11 May 2022 15:14:41 -0500
Subject: [PATCH 1/2] C++14 build fixes for older gcc #2333

---
 example/example.cpp             |  7 ++++---
 include/spdlog/common.h         | 16 ++++++++++++++++
 include/spdlog/fmt/bin_to_hex.h |  6 ++++--
 3 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/example/example.cpp b/example/example.cpp
index c379c746..9ccc4519 100644
--- a/example/example.cpp
+++ b/example/example.cpp
@@ -262,15 +262,16 @@ struct my_type
         : i(i){};
 };
 
-namespace fmt_lib = spdlog::fmt_lib;
+FMTLIB_BEGIN_NAMESPACE
 template<>
-struct fmt_lib::formatter<my_type> : fmt_lib::formatter<std::string>
+struct formatter<my_type> : formatter<std::string>
 {
     auto format(my_type my, format_context &ctx) -> decltype(ctx.out())
     {
-        return fmt_lib::format_to(ctx.out(), "[my_type i={}]", my.i);
+        return format_to(ctx.out(), "[my_type i={}]", my.i);
     }
 };
+FMTLIB_END_NAMESPACE
 
 void user_defined_example()
 {
diff --git a/include/spdlog/common.h b/include/spdlog/common.h
index 9ab886f5..ae51c745 100644
--- a/include/spdlog/common.h
+++ b/include/spdlog/common.h
@@ -126,6 +126,13 @@ using sink_ptr = std::shared_ptr<sinks::sink>;
 using sinks_init_list = std::initializer_list<sink_ptr>;
 using err_handler = std::function<void(const std::string &err_msg)>;
 #ifdef SPDLOG_USE_STD_FORMAT
+#    ifndef FMTLIB_BEGIN_NAMESPACE
+#        define FMTLIB_BEGIN_NAMESPACE \
+           namespace std {
+#        define FMTLIB_END_NAMESPACE \
+           }
+#    endif
+
 namespace fmt_lib = std;
 
 using string_view_t = std::string_view;
@@ -146,7 +153,16 @@ template<typename... Args>
 using wformat_string_t = std::wstring_view;
 #    endif
 #    define SPDLOG_BUF_TO_STRING(x) x
+
 #else // use fmt lib instead of std::format
+
+#    ifndef FMTLIB_BEGIN_NAMESPACE
+#        define FMTLIB_BEGIN_NAMESPACE \
+           namespace fmt {
+#        define FMTLIB_END_NAMESPACE \
+           }
+#    endif
+
 namespace fmt_lib = fmt;
 
 using string_view_t = fmt::basic_string_view<char>;
diff --git a/include/spdlog/fmt/bin_to_hex.h b/include/spdlog/fmt/bin_to_hex.h
index 93e5c28b..2a5d02c9 100644
--- a/include/spdlog/fmt/bin_to_hex.h
+++ b/include/spdlog/fmt/bin_to_hex.h
@@ -8,8 +8,10 @@
 #include <cctype>
 #include <spdlog/common.h>
 
-#if defined(__has_include) && __has_include(<version>)
-#    include <version>
+#if defined(__has_include)
+#    if __has_include(<version>)
+#        include <version>
+#    endif
 #endif
 
 #if __cpp_lib_span >= 202002L

From d3dee23e6c59624deadd350ca72e51eeb94ddbc5 Mon Sep 17 00:00:00 2001
From: Kevin Slattery <kslattery@gmail.com>
Date: Thu, 12 May 2022 18:55:08 -0500
Subject: [PATCH 2/2] Remove new macro, update example with correct way to
 specify fmt lib namespace when fmt_lib namespace alias cannot be used.

---
 example/example.cpp     | 11 +++++++++--
 include/spdlog/common.h | 16 ----------------
 2 files changed, 9 insertions(+), 18 deletions(-)

diff --git a/example/example.cpp b/example/example.cpp
index 9ccc4519..b348afb9 100644
--- a/example/example.cpp
+++ b/example/example.cpp
@@ -262,7 +262,14 @@ struct my_type
         : i(i){};
 };
 
-FMTLIB_BEGIN_NAMESPACE
+
+// Using a namespace alias like fmt_lib is not allowed when extending an existing namespace,
+// but the correct namespace can still be selected with the SPDLOG_USE_STD_FORMAT macro.
+#ifdef SPDLOG_USE_STD_FORMAT
+    namespace std {
+#else
+    namespace fmt {
+#endif
 template<>
 struct formatter<my_type> : formatter<std::string>
 {
@@ -271,7 +278,7 @@ struct formatter<my_type> : formatter<std::string>
         return format_to(ctx.out(), "[my_type i={}]", my.i);
     }
 };
-FMTLIB_END_NAMESPACE
+}
 
 void user_defined_example()
 {
diff --git a/include/spdlog/common.h b/include/spdlog/common.h
index ae51c745..9ab886f5 100644
--- a/include/spdlog/common.h
+++ b/include/spdlog/common.h
@@ -126,13 +126,6 @@ using sink_ptr = std::shared_ptr<sinks::sink>;
 using sinks_init_list = std::initializer_list<sink_ptr>;
 using err_handler = std::function<void(const std::string &err_msg)>;
 #ifdef SPDLOG_USE_STD_FORMAT
-#    ifndef FMTLIB_BEGIN_NAMESPACE
-#        define FMTLIB_BEGIN_NAMESPACE \
-           namespace std {
-#        define FMTLIB_END_NAMESPACE \
-           }
-#    endif
-
 namespace fmt_lib = std;
 
 using string_view_t = std::string_view;
@@ -153,16 +146,7 @@ template<typename... Args>
 using wformat_string_t = std::wstring_view;
 #    endif
 #    define SPDLOG_BUF_TO_STRING(x) x
-
 #else // use fmt lib instead of std::format
-
-#    ifndef FMTLIB_BEGIN_NAMESPACE
-#        define FMTLIB_BEGIN_NAMESPACE \
-           namespace fmt {
-#        define FMTLIB_END_NAMESPACE \
-           }
-#    endif
-
 namespace fmt_lib = fmt;
 
 using string_view_t = fmt::basic_string_view<char>;