kernel doesn't build anymore on 4.9-RC ?

[Gianmarco]

4.9-RC of a cvsup of 5 minutes ago.

--- make kernel ---
Warning: Object directory not changed from original /usr/obj/usr/src/sys/
FREEBSD
cc -O -pipe  -nostdinc -I/usr/include -I. -I/usr/src/sys/dev/aic7xxx/aicasm    
-D__FBSDID=__RCSID -c /usr/src/sys/dev/aic7xxx/aicasm/aicasm.c
cc -O -pipe  -nostdinc -I/usr/include -I. -I/usr/src/sys/dev/aic7xxx/aicasm    
-D__FBSDID=__RCSID -c /usr/src/sys/dev/aic7xxx/aicasm/aicasm_symbol.c
cc -O -pipe  -nostdinc -I/usr/include -I. -I/usr/src/sys/dev/aic7xxx/aicasm    
-D__FBSDID=__RCSID -c aicasm_gram.c
cc -O -pipe  -nostdinc -I/usr/include -I. -I/usr/src/sys/dev/aic7xxx/aicasm    
-D__FBSDID=__RCSID -c aicasm_macro_gram.c
cc -O -pipe  -nostdinc -I/usr/include -I. -I/usr/src/sys/dev/aic7xxx/aicasm    
-D__FBSDID=__RCSID -c aicasm_scan.c
cc -O -pipe  -nostdinc -I/usr/include -I. -I/usr/src/sys/dev/aic7xxx/aicasm    
-D__FBSDID=__RCSID -c aicasm_macro_scan.c
cc -O -pipe  -nostdinc -I/usr/include -I. -I/usr/src/sys/dev/aic7xxx/aicasm    
-D__FBSDID=__RCSID  -o aicasm aicasm.o aicasm_symbol.o aicasm_gram.o 
aicasm_macro_gram.o aicasm_scan.o aicasm_macro_scan.o -ll
cd /usr/obj/usr/src/sys/FREEBSD;  MAKEOBJDIRPREFIX=/usr/obj  MACHINE_ARCH=i386  
MACHINE=i386  OBJFORMAT_PATH=/usr/obj/usr/src/i386/usr/libexec  PERL5LIB=/
usr/obj/usr/src/i386/usr/libdata/perl/5.00503  GROFF_BIN_PATH=/usr/obj/usr/
src/i386/usr/bin  GROFF_FONT_PATH=/usr/obj/usr/src/i386/usr/share/groff_font  
GROFF_TMAC_PATH=/usr/obj/usr/src/i386/usr/share/tmac  DESTDIR=/usr/obj/usr/
src/i386  INSTALL="sh /usr/src/tools/install.sh"  PATH=/usr/obj/usr/src/i386/
usr/sbin:/usr/obj/usr/src/i386/usr/bin:/usr/obj/usr/src/i386/usr/games:/
sbin:/bin:/usr/sbin:/usr/bin  OBJFORMAT_PATH=/usr/obj/usr/src/i386/usr/
libexec:/usr/libexec make KERNEL=kernel depend
cc -c -O -pipe  -Wall -Wredundant-decls -Wnested-externs -Wstrict-prototypes  
-Wmissing-prototypes -Wpointer-arith -Winline -Wcast-qual  
-fformat-extensions -ansi  -nostdinc -I- -I. -I/usr/src/sys -I/usr/src/
sys/../include -I/usr/src/sys/contrib/dev/acpica -I/usr/src/sys/contrib/
ipfilter  -D_KERNEL -include opt_global.h  -mpreferred-stack-boundary=2 /usr/
src/sys/i386/i386/genassym.c
sh /usr/src/sys/kern/genassym.sh genassym.o > assym.s
awk: cmd. line:3:       sign = substr($1, length($1) - 3, 4)
awk: cmd. line:3:                                       ^ syntax error
awk: cmd. line:3: fatal: substr() cannot have 0 arguments
*** Error code 2

Stop in /usr/obj/usr/src/sys/FREEBSD.
*** Error code 1

--> end <--

The kernel file built fine on older 4.x .

Thanks for any input.