T070 tests portability

[David Bremner]

Tomi Ollila <tomi.ollila at iki.fi> writes:

> The page https://sourceware.org/gdb/onlinedocs/gdb/Returning.html
> talks something about gdb not knowing the return type if function
> was compiled without debug info... well, is this is the reason,
> perhaps we should allow testing w/o debug info compiled in.

The test suite overall assumes debug info is present; T000-basic tests
for this.

d