Enable Treat Warnings as Errors

AFNetworking.xcodeproj/project.pbxproj

@@ -1238,6 +1238,7 @@
 					"DEBUG=1",
 					"$(inherited)",
 				);
+				GCC_TREAT_WARNINGS_AS_ERRORS = YES;
 				GCC_WARN_64_TO_32_BIT_CONVERSION = YES;
 				GCC_WARN_ABOUT_RETURN_TYPE = YES_ERROR;
 				GCC_WARN_UNDECLARED_SELECTOR = YES;
@@ -1283,6 +1284,7 @@
 				ENABLE_STRICT_OBJC_MSGSEND = YES;
 				GCC_C_LANGUAGE_STANDARD = gnu99;
 				GCC_NO_COMMON_BLOCKS = YES;
+				GCC_TREAT_WARNINGS_AS_ERRORS = YES;
 				GCC_WARN_64_TO_32_BIT_CONVERSION = YES;
 				GCC_WARN_ABOUT_RETURN_TYPE = YES_ERROR;
 				GCC_WARN_UNDECLARED_SELECTOR = YES;