Possible Duplicate:
What does the -all_load linker flag do?
I see most static library require you to do it, so I add them in all of my projects, seems no side effect in adding this?
Possible Duplicate:
What does the -all_load linker flag do?
I see most static library require you to do it, so I add them in all of my projects, seems no side effect in adding this?
There is a side effect: build phase take much time.
-ObjC allow the static library to use objective-c specific stuffs like kvc or categories.
-all_load solve a bug in gcc/llvm, where -ObjC is not correctly used.
Read about why to use these flags in SO questions:
What does the -all_load linker flag do?
Objective-C categories in static library
And then think about if you need to use them or not