Error building ghc 6.10.3

[S. Günther]

Hello,

I'm trying to install ghc 6.10.3 for quite a while now on my
system (Mac OS X Tiger, Intel, Xcode 2.5) but I keep getting
the error:

Preprocessing library ghc-6.10.3...
/usr/libexec/gcc/i686-apple-darwin8/4.0.1/ld: can't locate file for: -lgmp

during the build phase. I went so far as to do:

sudo port -f uninstall installed
sudo rm -rf /opt/ /Library/Tcl/macports1.0/
/Library/Receipts/MacPorts*.pkg ~/.macports/

and reinstall MacPorts from scratch.
I'm reluctant to file a bug report because the last time I filed
one, it was an error on my side and not a bug in the ports
system and since a few bugs with this error message have
been filed but have been considered fixed, I presume there
is a high probability that I messed up. So I would like to ask
for pointers on where to look for things in the system which
might lead to such an error message, and which can be fixed
by myself.

Thanks in advance
Stephan Günther
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