Geoff Chappell - Software Analyst
This option sets the machine type for the target platform.
The required argument is a simple keyword. Permitted values are AM33, AMD64, ARM, I386, IA64, IX86, M32R, MIPS, MIPS16, MIPSFPU, MIPSFPU16, MIPSR41XX, PPC, PPCFP, SH3, SH3DSP, SH4, SH5, THUMB, TRICORE, X86 and X86-64. Anything else causes a warning (LNK4012).
Several of the keywords are aliases: I386 and IX86 for X86, and X86-64 for AMD64.
The text for warning LNK4012 omits AMD64. So too does the help text produced by the lib /? command.