unknown directive: .gnu_attribute 4, 0

[于善伟]

cc -target mipsel-unknown-freebsd12.0 
--sysroot=/home/ysw/obj/mips.mipsel/usr/home/ysw/freebsd12/tmp 
-B/home/ysw/obj/mips.mipsel/usr/home/ysw/freebsd12/tmp/usr/bin -O -pipe 
-I/usr/home/ysw/freebsd12/lib/csu/common 
-I/usr/home/ysw/freebsd12/lib/libc/include -G0 -EL -mabi=32 
-msoft-float   -MD  -MF.depend.crti.o -MTcrti.o -std=gnu99 
-Wsystem-headers -Werror -Wall -Wno-format-y2k -W -Wno-unused-parameter 
-Wstrict-prototypes -Wmissing-prototypes -Wpointer-arith -Wreturn-type 
-Wcast-qual -Wwrite-strings -Wswitch -Wshadow -Wunused-parameter 
-Wcast-align -Wchar-subscripts -Winline -Wnested-externs 
-Wredundant-decls -Wold-style-definition -Wno-pointer-sign 
-Wthread-safety -Wno-empty-body -Wno-string-plus-int 
-Wno-unused-const-variable -Qunused-arguments    -c 
/usr/home/ysw/freebsd12/lib/csu/mips/crti.S -o crti.o
/usr/home/ysw/freebsd12/lib/csu/mips/crti.S:4:2: error: unknown directive
  .gnu_attribute 4, 0
  ^
*** Error code 1
this line added in:

https://svnweb.freebsd.org/base/head/lib/csu/mips/crti.S?r1=205112&r2=308712