With older gcc's:
In file included from drivers/usb/class/cdc-acm.c:63:
include/linux/usb_cdc.h:117: field `bDetailData' has incomplete type
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff -puN include/linux/usb_cdc.h~usb_cdc-build-fix include/linux/usb_cdc.h
 
        /* type is associated with mdlm_desc.bGUID */
        __u8    bGuidDescriptorType;
-       __u8    bDetailData[];
+       __u8    bDetailData[0];
 } __attribute__ ((packed));
 
 /*-------------------------------------------------------------------------*/