$ spack install gdal

$ spack module tcl refresh proj
==> You are about to regenerate tcl module files for:

-- linux-ubuntu16.04-x86_64 / gcc@5.4.0 -------------------------
tym5zkx proj@5.0.1

==> Do you want to proceed? [y/n] y
==> Regenerating tcl module files
==> Warning: Could not write module file [/usr/local/pkg/temp/spack/share/spack/modules/linux-ubuntu16.04-x86_64/proj-5.0.1-gcc-5.4.0-tym5zkx]
==> Warning: 	--> [Errno 2] No such file or directory: '/usr/local/pkg/temp/spack/var/spack/stage/proj-5.0.1-tym5zkxbywyt2pcq33232zgpokq6gwrj' <--