Intention
make an ebuild for the gentoo oevrlay guru

Describe the bug

-- Configuring done
-- Generating done
CMake Error:
  Running

   '/usr/bin/ninja' '-C' '/var/tmp/portage/sys-cluster/dyninst-11.0.1/work/dyninst-11.0.1_build' '-t' 'recompact'

  failed with:

   ninja: error: build.ninja:120: bad $-escape (literal $ must be written as $$)

To Reproduce
cmake -C /var/tmp/portage/sys-cluster/dyninst-11.0.1/work/dyninst-11.0.1_build/gentoo_common_config.cmake -G Ninja -DCMAKE_INSTALL_PREFIX=/usr -DSTERILE_BUILD=YES -DENABLE_STATIC_LIBS=NO -DADD_VALGRIND_ANNOTATIONS=yes -DBUILD_DOCS=no -DUSE_OpenMP=yes -DCMAKE_BUILD_TYPE=Gentoo -DCMAKE_TOOLCHAIN_FILE=/var/tmp/portage/sys-cluster/dyninst-11.0.1/work/dyninst-11.0.1_build/gentoo_toolchain.cmake /var/tmp/portage/sys-cluster/dyninst-11.0.1/work/dyninst-11.0.1

It doesn't happen if I set -DBUILD_RTLIB=NO

Expected behavior
build successfully

System (please complete the following information):
gentoo

full log here https://gist.github.com/Alessandro-Barbieri/8ba9ad624e826ea7cef3048c6e6b7030