/usr/src/glibc/debian/debhelper.in/libc-otherbuild.install is in glibc-source 2.23-0ubuntu3.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 | # This file is used for making NPTL and other
# optimized libraries.
TMPDIR/SLIBDIR/*.so* SLIBDIR
|