Configuring a cross compile with --with_sysroot

[Michiel Bacchiani]

I am attempting to cross compile GCC on x86_64 for arm. I created a
chroot with the arm system with the target system headers.

I configure the build with

${ROOT}/gcc-4.9.4/configure \
    --prefix=${ROOT}/toolchain \
    --program-prefix=arm-linux-gnueabihf- \
    --enable-languages=c,c++ \
    --with-gnu-as \
    --with-as=${ROOT}/toolchain/bin/arm-linux-gnueabihf-as \
    --with-gnu-ld \
    --with-ld=${ROOT}/toolchain/bin/arm-linux-gnueabihf-ld \
    --with-sysroot=/var/lib/schroot/chroots/trusty-armhf \
    --target=arm-linux-gnueabihf \
    --disable-multilib \
    --disable-nls

It succeeds in building the first compiler and then starts to use it

./gcc/xgcc .....

which dies with

make[2]: *** [_addvsi3.o] Error 1
In file included from
/var/lib/schroot/chroots/trusty-armhf/usr/include/stdio.h:27:0,
                 from
/usr/local/suteki/chn_20160901/gcc-4.9.4/libgcc/../gcc/tsystem.h:87,
                 from
/usr/local/suteki/chn_20160901/gcc-4.9.4/libgcc/libgcc2.c:27:
/var/lib/schroot/chroots/trusty-armhf/usr/include/features.h:374:25:
fatal error: sys/cdefs.h: No such file or directory
 #  include <sys/cdefs.h>
                         ^
compilation terminated.

The header it cannot find is present but in

/var/lib/schroot/chroots/trusty-armhf/usr/include/arm-linux-gnueabihf/sys/cdefs.h

It seems only <sysroot>/usr/include is on the search path, not the
additional <sysroot>/usr/include/<target> which is needed to find this
header.

How can I add this search path? Searching for header in the
configuration instruction page came up empty...


Michiel.