Compilation Error in ISA.C

[dressguard]

Getting the following error message from latest git version when doing the following according to the instructions on the web site:
git clone git://git.ipxe.org/ipxe.git
cd ipxe/src
make
->
drivers/bus/isa.c: In function ‘isabus_probe’:
drivers/bus/isa.c:112:18: error: array subscript is above array bounds [-Werror=array-bounds]
cc1: all warnings being treated as errors
make: *** [bin/isa.o] Error 1

Any ideas?