[isa] Avoid spurious compiler warning on gcc 4.7

gcc 4.7 produces a spurious warning about an array subscript being out
of bounds.  Use a pointer dereference instead of an array lookup to
inhibit this spurious warning.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

diff --git a/src/drivers/bus/isa.c b/src/drivers/bus/isa.c
index 9b562c6646c8457f179a82652f74a04b704949d3..da0c43c60b48867595f2c01e8e63e0e7b4c144fb 100644 (file)
--- a/src/drivers/bus/isa.c
+++ b/src/drivers/bus/isa.c
@@ -46,9 +46,9 @@ static isa_probe_addr_t isa_extra_probe_addrs[] = {
 #endif
 
 #define ISA_IOADDR( driver, ioidx )                                      \
-       ( ( (ioidx) < 0 ) ?                                               \
-         isa_extra_probe_addrs[ (ioidx) + ISA_EXTRA_PROBE_ADDR_COUNT ] : \
-         (driver)->probe_addrs[(ioidx)] )
+       ( ( (ioidx) >= 0 ) ?                                              \
+         (driver)->probe_addrs[(ioidx)] :                                \
+         *( isa_extra_probe_addrs + (ioidx) + ISA_EXTRA_PROBE_ADDR_COUNT ) )
 
 static void isabus_remove ( struct root_device *rootdev );