If __IPHONE_13_0 is not defined (which is the case with suppose Xcode 10.3 which does not have iOS SDK 13), then this will be replaced with 0 and the condition will resolve to true which would cause compile time errors when compiled with iOS SDK less than 13. This should be replaced with the following condition,
In the file AbstractActionSheetPicker.m there is a line of code to do conditional compilation
#if __IPHONE_OS_VERSION_MAX_ALLOWED >= __IPHONE_13_0
If __IPHONE_13_0 is not defined (which is the case with suppose Xcode 10.3 which does not have iOS SDK 13), then this will be replaced with 0 and the condition will resolve to true which would cause compile time errors when compiled with iOS SDK less than 13. This should be replaced with the following condition,
#if defined(__IPHONE_13_0) && __IPHONE_OS_VERSION_MAX_ALLOWED >= __IPHONE_13_0
This will first check if the macro is there, if it is not defined then we would go to the else part which is what is intended.