add 'ldd' to cross-tools ?

[Oleksandr Tymoshenko]

On 04/01/2012 2:23 PM, Luigi Rizzo wrote:
> Hi,
> in doing cross-builds of picobsd, i found i need a cross-version
> of "ldd" so i can run it on the host to detect which shared libraries
> are used by binaries on the target architecture
> (for amd64->i386 there is a partial workaround, but don't know
> if it works in other cases)
>
> Is there any concern in adding usr.bin/ldd to the list of cross-tools
> in Makefile.inc1 ? It is a small program and should not increase
> the build time in any significant way.
>
> Otherwise, does anyone know the magic to build a cross-arch
> version of a program in the FreeBSD source tree ?

AFAIK ldd can't be used as a cross-tool. It sets some env
variables for loader (e.g. ld-elf.so), calls execve
or dlopen and relies on ld.so to print all the required data.
You might get away with it on amd64/i386 host-target pair
but it's not going to work for i386/arm or i386/mips pair.