Fix clang-14 fmt compilation errors

components/pango_core/include/pangolin/utils/fmt.h

@@ -9,10 +9,33 @@
 namespace pangolin
 {
 
+// Wraps fmt::format to conform to its compile-time checked APIs.
+// 
+// With more recent versions of fmt and more recent compilers,
+// more compile-time checking is enabled in fmt by default.
+// 
+// Pangolin logging currently relies on some runtime 
+// format string construction, so we add a layer of indirection here.
+//  
+// Alternatively we could eliminate the use of runtime format strings in Pangolin.
+template <typename TFmt, typename... TArgs>
+std::string format(TFmt&& fmt, TArgs&&... args) {
+  if constexpr (std::is_same_v<TFmt, fmt::format_string<TArgs...>>) {
+    // The type of the fmt string is known at compile-time, forward as-is 
+    return fmt::format(fmt, std::forward<TArgs>(args)...);    
+  } else if constexpr (std::is_convertible_v<TFmt, std::string_view>) {
+    // The type of the fmt string is not known at compile-time, wrap in fmt::runtime
+    return fmt::format(fmt::runtime(fmt), std::forward<TArgs>(args)...);
+  } else {
+    // The fmt string is some other type, like a `fmt::text_style`, forward as-is
+    return fmt::format(fmt, std::forward<TArgs>(args)...);
+  }
+}
+
 template <typename... TArgs>
 void println(TArgs&&... args)
 {
-  fmt::print(std::forward<TArgs>(args)...);
+  fmt::print(fmt::runtime(format(std::forward<TArgs>(args)...)));
   std::cout << std::endl;
 }
 

components/pango_core/include/pangolin/utils/logging.h

@@ -124,7 +124,7 @@ struct Log {
       const char* assertion_statement, Args... args)
   {
     if constexpr (sizeof...(args) > 0) {
-      const std::string arg_string = fmt::format(std::forward<Args>(args)...);
+      const std::string arg_string = pangolin::format(std::forward<Args>(args)...);
       logImpl(kind, sFile, sFunction, nLine, assertion_statement, arg_string);
     } else {
       logImpl(kind, sFile, sFunction, nLine, assertion_statement, "");
@@ -137,7 +137,7 @@ struct Log {
       const char* assertion_statement, Args... args)
   {
     if constexpr (sizeof...(args) > 0) {
-      const std::string arg_string = fmt::format(std::forward<Args>(args)...);
+      const std::string arg_string = pangolin::format(std::forward<Args>(args)...);
       logImpl(kind, sFile, sFunction, nLine, assertion_statement, arg_string);
       throw std::runtime_error(arg_string);
     } else {