[Haskell-beginners] GHC-generated executables size

[Daniel Fischer]

On Saturday 16 October 2010 21:32:27, . wrote:
> I have seen, however, that I have 2 versions of gtk (0.11.2 and 0.11.0)
> on the system. I will try to find out which one was actually used when I
> called "ghc --make guiMain"; how would I go about that?
>

Normally, ghc picks the later version. When compiling, you can see which 
version is used by giving the appropriate verbosity flag (-v2 or greater).
After the fact, the only way I know is

$ nm executable | grep stginit_gtk | more (or less)

and then you'll see the z-encoded package version, lines like

080ca5dc T __stginit_gtkzm0zi11zi2_Stuff

for gtk-0.11.2.

> > > and recompiling and re-linking my little program does not change
> > > its size ...
> >
> > Possibly the packages have been built with -spilt-objs originally, or
> > your GHC doesn't support split-objs, in either case, sorry for the
> > inconvenience
> >
> > :-/
> >
> > gtk contains apparently hundreds of thousands of modules, so it may be
> > the module-initialisation functions. Quick test:
> >
> > $ nm yourexecutable | grep stginit | wc -l
>
> I tried that, there are almost 900 matches.
>

Hm, shouldn't nearly take you to 20M.

> > > Any other idea what I might be doing wrong?
> >
> > Nothing, probably.
> >
> > What ghc version are you using, on which platform (OS, arch), which
> > packages does your executable need?
>
> I am using Ubuntu 10.10, ghc 6.12.1, on a 4-core AMD Phenom.
> The program I am compiling needs these packages:
>  gtk, Text.Parsec, Time, Database.HDBC.Sqlite3, Locale,
> Data.ByteString.Lazy.
>

No obvious suspect.
Depending on how curious you are, you could split off small sub-programmes 
to see what's taking a lot of space. But that's going to be tedious.

You could ask on IRC (#haskell) whether anybody knows about huge 
executables with gtk, or on haskell-cafe, on the gtk2hs mailing list, or 
you could open a ticket at http://hackage.haskell.org/trac/gtk2hs/ or 
http://hackage.haskell.org/trac/ghc/newticket?type=bug whichever you 
consider more likely to be responsible (you needn't create an account for 
either bug-tracker, both have guest accounts with the guest password in 
plain view - though you may need to look for it a bit). But first ask 
elsewhere.

>
> --Christian