This maps the -pthread option to -lpthread - this isn't 100% correct, since handling this correctly is quite complex, and on some platforms requires additional -D options and on some implies linking against a different libc, but this works better than just ignoring the option.
The other change passes the -x option across to clang, which allows compiling .c files as Objective-C and so on. For some reason a lot of configure scripts seem to be under the misguided impression that this is a sensible thing to do.
David
Index: utils/ccc