Add OTHER_SWIFT_FLAGS = "-Xfrontend -warn-long-function-bodies=500" to trace long compilation issues.

XCode/Swifter.xcodeproj/project.pbxproj

@@ -1043,6 +1043,7 @@
 				MACOSX_DEPLOYMENT_TARGET = 10.9;
 				METAL_ENABLE_DEBUG_INFO = YES;
 				ONLY_ACTIVE_ARCH = YES;
+				OTHER_SWIFT_FLAGS = "-Xfrontend -warn-long-function-bodies=500";
 				SDKROOT = macosx;
 				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
 				SWIFT_VERSION = 4.0;
@@ -1094,6 +1095,7 @@
 				MACOSX_DEPLOYMENT_TARGET = 10.9;
 				METAL_ENABLE_DEBUG_INFO = NO;
 				ONLY_ACTIVE_ARCH = NO;
+				OTHER_SWIFT_FLAGS = "-Xfrontend -warn-long-function-bodies=500";
 				SDKROOT = macosx;
 				SWIFT_OPTIMIZATION_LEVEL = "-Owholemodule";
 				SWIFT_VERSION = 4.0;