diff --git a/include/spdlog/common.h b/include/spdlog/common.h
index 5393dfc9..07e0ee59 100644
--- a/include/spdlog/common.h
+++ b/include/spdlog/common.h
@@ -112,18 +112,12 @@
         catch (const std::exception &) {}
 #endif
 
-#ifdef _MSC_VER
-#define SPDLOG_CPLUSPLUS _MSVC_LANG
-#else
-#define SPDLOG_CPLUSPLUS __cplusplus
-#endif
-
 #if SPDLOG_CPLUSPLUS > 201703L
-#define SPDLOG_CONSTEVAL consteval
+#    define SPDLOG_CONSTEVAL consteval
 #elif SPDLOG_CPLUSPLUS < 201402L
-#define SPDLOG_CONSTEVAL 
+#    define SPDLOG_CONSTEVAL 
 #else
-#define SPDLOG_CONSTEVAL constexpr
+#    define SPDLOG_CONSTEVAL constexpr
 #endif
 
 namespace spdlog {
@@ -167,11 +161,6 @@ struct format_string_wrapper
         : fmt_{fmtstr}
         , loc_{loc}
     {}
-#elif !defined(SPDLOG_USE_STD_FORMAT) && FMT_VERSION < 80000
-    SPDLOG_CONSTEXPR format_string_wrapper(const Char* fmtstr, details::source_location loc = details::source_location::current())
-        : fmt_{fmtstr}
-        , loc_{loc}
-    {}
 #else
     template <typename S>
     requires std::is_convertible_v<S, T>
diff --git a/include/spdlog/details/source_location.h b/include/spdlog/details/source_location.h
index 7eef1484..7d5e54e2 100644
--- a/include/spdlog/details/source_location.h
+++ b/include/spdlog/details/source_location.h
@@ -4,8 +4,14 @@
 
 #include <cstdint>
 
+#ifdef _MSC_VER
+#    define SPDLOG_CPLUSPLUS _MSVC_LANG
+#else
+#    define SPDLOG_CPLUSPLUS __cplusplus
+#endif
+
 #ifdef __has_include
-#    if __has_include(<source_location>) && __cplusplus >= 202002L
+#    if __has_include(<source_location>) && SPDLOG_CPLUSPLUS >= 202002L
 #        include <source_location>
 #        define SPDLOG_SOURCE_LOCATION
 #    endif
@@ -23,57 +29,57 @@ public:
 #if  !defined(__apple_build_version__) && defined(__clang__) &&            \
     (__clang_major__ >= 9)
   static constexpr source_location
-  current(const char *fileName = __builtin_FILE(),
-          const unsigned lineNumber = __builtin_LINE(),
-          const char *functionName = __builtin_FUNCTION(),
-          const unsigned columnOffset = __builtin_COLUMN()) noexcept
+  current(const char *file = __builtin_FILE(),
+          const unsigned line = __builtin_LINE(),
+          const char *function = __builtin_FUNCTION(),
+          const unsigned column = __builtin_COLUMN()) noexcept
 #elif defined(__GNUC__) &&                                                    \
     (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 8))
   static constexpr source_location
-  current(const char *fileName = __builtin_FILE(),
-          const unsigned lineNumber = __builtin_LINE(),
-          const char *functionName = __builtin_FUNCTION(),
-          const unsigned columnOffset = 0) noexcept
+  current(const char *file = __builtin_FILE(),
+          const unsigned line = __builtin_LINE(),
+          const char *function = __builtin_FUNCTION(),
+          const unsigned column = 0) noexcept
 #elif defined(_MSC_VER) && (_MSC_VER > 1925)
   static constexpr source_location
-  current(const char *fileName = __builtin_FILE(),
-          const unsigned lineNumber = __builtin_LINE(),
-          const char *functionName = __builtin_FUNCTION(),
-          const unsigned columnOffset = __builtin_COLUMN()) noexcept
+  current(const char *file = __builtin_FILE(),
+          const unsigned line = __builtin_LINE(),
+          const char *function = __builtin_FUNCTION(),
+          const unsigned column = __builtin_COLUMN()) noexcept
 #else
   static constexpr source_location
-  current(const char *fileName = "unsupported",
-          const unsigned lineNumber = 0,
-          const char *functionName = "unsupported",
-          const unsigned columnOffset = 0) noexcept
+  current(const char *file = nullptr,
+          const unsigned line = 0,
+          const char *function = nullptr,
+          const unsigned column = 0) noexcept
 #endif
   {
-    return source_location(fileName, lineNumber, functionName, columnOffset);
+    return source_location(file, line, function, column);
   }
 
   source_location(const source_location &) = default;
   source_location(source_location &&) = default;
 
-  constexpr const char *file_name() const noexcept { return fileName; }
+  constexpr const char *file_name() const noexcept { return file_; }
 
-  constexpr const char *function_name() const noexcept { return functionName; }
+  constexpr const char *function_name() const noexcept { return function_; }
 
-  constexpr unsigned line() const noexcept { return lineNumber; }
+  constexpr unsigned line() const noexcept { return line_; }
 
-  constexpr unsigned column() const noexcept { return columnOffset; }
+  constexpr unsigned column() const noexcept { return column_; }
 
 private:
-  constexpr source_location(const char *fileName,
-                            const unsigned lineNumber,
-                            const char *functionName,
-                            const unsigned columnOffset) noexcept
-      : fileName(fileName), lineNumber(lineNumber), functionName(functionName),
-        columnOffset(columnOffset) {}
+  constexpr source_location(const char *file,
+                            const unsigned line,
+                            const char *function,
+                            const unsigned column) noexcept
+      : file_(file), line_(line), function_(function),
+        column_(column) {}
 
-  const char *fileName;
-  const unsigned lineNumber;
-  const char *functionName;
-  const unsigned columnOffset;
+  const char *file_;
+  const unsigned line_;
+  const char *function_;
+  const unsigned column_;
 };
 } // namespace details
 } // namespace spdlog