cross-compiling strace 4.20 for ARM

[Felix von Leitner]

> > Are you sure about this?
> It's _XOPEN_SOURCE, but as configure.ac contains AC_USE_SYSTEM_EXTENSIONS,
> I suppose _GNU_SOURCE is defined anyway.

I do get the symbol when I define _XOPEN_SOURCE:

  $ printf "#include <limits.h>\\nIOV_MAX" | arm-linux-gnueabi-gcc -D_XOPEN_SOURCE -E -

Something else must be broken here.
Not sure what though.

Felix