[Haskell-cafe] where does ghc specify ar options

[Duncan Coutts]

On Sun, 2009-03-08 at 22:44 -0500, Alexy Khrabrov wrote:
> When bootstrapping cabal-install 0.6.2 on Mac OSX Leopard (Intel), I
> get a problem when linking:
> 
> Linking dist/build/cabal/cabal ...
> ld: in /private/var/folders/mw/mwJSf7ErEa4w8nWyKyyqD++++TY/-Tmp-/zlib-0.5.0.0/dist/build/libHSzlib-0.5.0.0.a,
> archive has no table of contents
> 
> This had happened with other ar'chives on my Mac before where it
> hadn't for some others.  In all cases the fix was to make sure ranlib
> is run on the archive in question, or s is passed to ar during the
> creation.  I have the latest XCode 312m gcc build 5490, and ghc 6.10.1
> from MacPorts.
> 
> In order to ensure ar cr becomes ar crs, I need to find out where in
> the ghc build process is it known how to create .a files?  Where can
> an "ar cr" be changed to "ar crs" on a system-wide ghc build basis?

We'll need some help from you to investigate this. Cabal does run ranlib
on libraries after it installs them. See updateLibArchive in
Distribution/Simple/GHC.hs in the Cabal source code. You'll see in the
code it looks for ranlib and ar. If neither are available it issues a
warning and installs anyway. Perhaps on OSX it should be an error rather
than a warning.

So we'll want to check that it's really being run when the zlib package
is being built. You can run any cabal command with -v or -v3 to see what
commands it runs.

BTW, how did you get the package installed in that location? Did it
involve copying into a temp dir and copying again? I believe that on
OSX, copying a .a file breaks the ar index. This is because for reasons
best known to themselves Apple decided that the index is only valid if
its timestamp is the same as the last modification time of the file.

Duncan