Meyers singleton jsc error extractor

Reviewed By: mhorowitz

Differential Revision: D6554142

fbshipit-source-id: f586cd7030130e4ccb069f9aed8fb1364c527e54

Author: johnislarry

ReactCommon/jschelpers/JSCHelpers.cpp

@@ -147,17 +147,8 @@ void JSException::buildMessage(JSContextRef ctx, JSValueRef exn, JSStringRef sou
 
 namespace ExceptionHandling {
 
-#if __clang__
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wglobal-constructors"
-#endif
-
 PlatformErrorExtractor platformErrorExtractor;
 
-#if __clang__
-#pragma clang diagnostic pop
-#endif
-
 }
 
 JSObjectRef makeFunction(

ReactCommon/jschelpers/JSCHelpers.h

@@ -51,7 +51,7 @@ namespace ExceptionHandling {
     // method@filename[:line[:column]]
     std::string stack;
   };
-  using PlatformErrorExtractor = std::function<ExtractedEror(const std::exception &ex, const char *context)>;
+  typedef ExtractedEror(*PlatformErrorExtractor)(const std::exception &ex, const char *context);
   extern PlatformErrorExtractor platformErrorExtractor;
 }