hpc markup: Prelude.foldr1: empty list

[jedbrown]

While testing code coverage for my new package, I noticed this.

$ ghc-6.8.2 -fhpc --make tests.hs -o tests
$ ./tests 200
flatten flatten          : OK, passed 200 tests.
reshape flatten          : OK, passed 200 tests.
rank                     : OK, passed 200 tests.
shape size               : OK, passed 200 tests.
size                     : OK, passed 200 tests.
$ hpc markup tests --include carray
Writing: hpc_index.html
hpc: Prelude.foldr1: empty list
$ hpc version
hpc tools, version 0.6
$ hpc markup tests --include nonexistent
Writing: hpc_index.html
hpc: Prelude.foldr1: empty list