How can I modify -march parameter gracefully when I abuild command? Using abuild the default is -march=i586 -mtune=generic, is there a place to modify this parameter gracefully? and I have my best minimum kernel configure (best-mini.conf), how can I use my .conf file gracefully in abuild script?

6 	586/K5/5x86/6x86/6x86MX 	(-mtune=generic ; SIMD assembly modules enabled based on simple compile test and/or presence of CPU flag) 	1000 HZ 	Voluntary Kernel Preemption (Desktop) 	32