That suggestion was completely misguided. Compiling with `-split-objs` makes a library _grow_ in size, but makes executables that link against it _smaller_.
Size of `libHSCabal-1.22.2.0` obtained by running `cabal install Cabal==1.22.2.0 --with-ghc=ghc-x.x.x (--enable-split-objs)`, on 64bit Ubuntu:
default --enable-split-objs
7.8.4: 19Mb 46Mb
7.10.1: 21Mb 52Mb
So the 7.10 versions are indeed somewhat larger, but I wouldn't call it ballooned or bloated. Note that a ghc build compiles the libraries with -O2 , which increases the binary size another 5% or so.
All these numbers are not far off from the ones you were getting. I think you have been comparing a 7.8.4 build of Cabal without split objects, with a 7.10.1 build of Cabal with split objects.
I don't think there is a bug here.
-Thomas
P.S. To show that binary sizes not only grow with new ghc releases, here is the same experiment with random: