In torsocks' configure.ac, libc_name is determined by means of ldd /usr/bin/yes which is then grepped for libc.
On a uClibc system I use, ldd /usr/bin/yes yields two entries, namely
libc.so.0 => ... ld64-uClibc.so.0 => ...
The resulting string begins with quotation mark, ends with quotation mark and contains newline character.
At some point during the configuration process (I have not figured out when exactly), the aforementioned string is trimmed erroneously. In my case, the first line is left out and the second one is discarded. The remaining chunk, with the opening quotation mark but without the closing one, ends up in another configuration file, producing a line like
SOME_VARIABLE="libc.so.0
without the closing quotation mark. Build cannot proceed from there.
The libc determination process thus needs to be fixed.
My hotfix was to change
grep 'libc.'
to
grep '\slibc.'
but I can't suggest the proper solution as I'm not experienced with shell scripts. I will perform a test if provided with (a link to) a relevant standalone patch for torsocks-2.2.0 or torsocks-2.3.0.