Strange errors building the data-default package

I'm getting a number of strange error messages while trying to cabal install data-default. The same basic phenomenon happens for that package even in a fresh sandbox. I can install other packages with no problem.

The error messages are of the following form, but occur for each of the 4 data-default-instances- packages:

[1 of 1] Compiling Data.Default.Instances.OldLocale ( Data\Default\Instances\OldLocale.hs, dist\dist-sandbox-6a114df1\build\Data\Default\Instances\OldLocale.o ) C:\Program Files (x86)\MinGHC-7.10.1\ghc-7.10.1\mingw\bin\ar.exe: dist/dist-sandbox-6a114df1\build\libHSdata-default-instances-old-locale-0.0.1-6jcjjaR25tK4x3nJhHHjFM.a-8696\libHSdata-default-instances-old-locale-0.0.1-6jcjjaR25tK4x3nJhHHjFM.a: No such file or directory

Any idea what's going on?