netbsd-9/amd64 build mixes 32 bit objects

Hello

Buiilding netbsd-9 for amd64 on amd64, I used build-sh -Uuom amd64 build
It fails because it mixes 32 bit and 64 bit (see log snipped below.

What did I do wrong?

#     build  libgcc_s/libgcc_s.so.1.0
rm -f libgcc_s.so.1.0
/home2/manu/netbsd9/src-amd64/tooldir.NetBSD-9.2_STABLE-amd64/bin/x86_64--netbsd
-gcc -nodefaultlibs -shared -Wl,-soname,libgcc_s.so.1  -Wl,--warn-shared-textrel
 -Wl,-Map=libgcc_s.so.1.map   -m32 --sysroot=/home2/manu/netbsd9/src-amd64/destd
ir.amd64 -nodefaultlibs -Wl,-z -Wl,nodelete -Wl,--version-script=/home2/manu/net
bsd9/src-amd64/external/gpl3/gcc/lib/libgcc/libgcc_s/libgcc.map -Wl,-z,relro  -o
 libgcc_s.so.1.0.tmp  -Wl,-rpath,/usr/lib/i386  -L=/usr/lib/i386 -Wl,-x  -Wl,--w
hole-archive libgcc_s_pic.a  -Wl,--no-whole-archive -m32
/home2/manu/netbsd9/src-amd64/tooldir.NetBSD-9.2_STABLE-amd64/lib/gcc/x86_64--ne
tbsd/7.5.0/../../../../x86_64--netbsd/bin/ld: i386:x86-64 architecture of input 
file `/home2/manu/netbsd9/src-amd64/destdir.amd64/usr/lib/../lib/i386/crti.o' is
 incompatible with i386 output
(many other similar)

-- 
Emmanuel Dreyfus
[email protected]