This package supports working with patch files using quilt.

To regenerate the quilt series file run:
./gen-quilt-series.sh

Setup environment:
export QUILT_PATCHES=$PWD

Setup the source:
./quilt-patch.sh

Create a new patch:
cd glibc-2.17-c758a686/
quilt new glibc-rh1234622.patch
quilt add ports/sysdeps/unix/sysv/linux/aarch64/nptl/libpthread.abilist
vi ports/sysdeps/unix/sysv/linux/aarch64/nptl/libpthread.abilist
quilt refresh
cd ..
git add glibc-rh1234622.patch
<Then edit the glibc.spec file to build with the new patch>
e.g.
...
PatchXXXX: glibc-rh1234622.patch
...
%patchXXXX -p1
...
git add glibc.spec
git commit

You're done!