Option to compile for both AMD64 and EM64T?

[Justin Palmer]

Hi,

Since the differences between AMD64 and EM64T are minor, will GCC have an option to compile applications for both?

Linux-Kernel Archive reference:
http://www.ussg.iu.edu/hypermail/linux/kernel/0402.3/0276.html

Currently, the -mtune, -march, and -mcpu values must specify one of: nocona, k8, opteron, athlon64, or athlon-fx.  My software group has been using i686 to build one executable for both Intel and AMD 32-bit processors and would like to build one executable for their 64-bit processors.

Also, do the docs need updated for -m64 or is that option really for AMD64 only?

Thanks,
Justin