the setxattr() function and the attr/xattr.h header be available. The
default is to autodetect whether support is possible.
+--disable-multithreaded-compression
+ By default, data will be compressed using multiple threads when writing
+ a WIM, unless only 1 processor is detected. Specify this option to
+ disable support for this.
+
--enable-ssse3-sha1
Use a very fast assembly language implementation of SHA1 from Intel.
Only use this if the build target supports the SSSE3 instructions.