tar no windows falha ao extrair o link simbólico do arquivo

Ao tentar instalar o GTK com vcpkg, ele falha ao extrair libexpat-libexpat-R_2_2_6.tar.gz :

Building package expat[core]:x64-windows...
-- Downloading https://github.com/libexpat/libexpat/archive/R_2_2_6.tar.gz...
-- Extracting source C:/Users/USER/git/vcpkg/downloads/libexpat-libexpat-R_2_2_6.tar.gz
CMake Error at scripts/cmake/vcpkg_execute_required_process.cmake:56 (message):
    Command failed: C:/Program Files/CMake/bin/cmake.exe;-E;tar;xjf;C:/Users/USER/git/vcpkg/downloads/libexpat-libexpat-R_2_2_6.tar.gz
    Working Directory: C:/Users/USER/git/vcpkg/buildtrees/expat/src/TEMP
    Error code: 1
    See logs for more information:
      C:\Users\USER\git\vcpkg\buildtrees\expat\extract-err.log

extract-err.log:

CMake Error: Problem with archive_write_header(): Can't create ''
CMake Error: Current file: libexpat-R_2_2_6/README.md
CMake Error: Problem extracting tar: C:/Users/USER/git/vcpkg/downloads/libexpat-libexpat-R_2_2_6.tar.gz

E executar tar manualmente resulta em:

> tar xjf C:/Users/USER/git/vcpkg/downloads/libexpat-libexpat-R_2_2_6.tar.gz
libexpat-R_2_2_6/README.md: Can't create '\\\\?\\C:\\Users\\USER\\git\\vcpkg\\buildtrees\\expat\\src\\TEMP\\libexpat-R_2_2_6\\README.md'
tar: Error exit delayed from previous errors.

Versões:

• Microsoft Windows [versão 10.0.17763.437]
• cmake versão 3.14.2
• bsdtar 3.3.2 - libarchive 3.3.2 zlib/1.2.5.f-ipp
• vcpkg 2018.11.23-nohash (commit 0907798)

Editar:

O erro tar é esperado, o problema se manifesta no cmake, onde a saída esperada (consulte extract-err.log) deve ser:

cmake -E tar: warning: skipping symbolic link "libexpat-R_2_2_6/README.md" -> "expat/README.md".

Editar:

Parece que este é um problema ativo do cmake https://gitlab.kitware.com/cmake/cmake/issues/19102