On 16 Jun 2003 16:59:07 +0900 Jens Petersen wrote:

Did anyone ever manage to get gtk2hs working with ghci-5.04.3? When I try to load it I get:

% ghci-5.04.3 -package gtk2 : Loading package data ... linking ... done. Loading package gtk2 ...

GHCi runtime linker: fatal error: I found a duplicate definition for symbol __stginit_Arrow whilst processing object file /usr/lib/ghc-5.04.3/gtk2hs/gtk2hs.o

My brief investigation into this revealed that __stginit_Arrow is defined in HSlang.o (ghci's object file for package lang) and this is the only standard package in which it is defined. __stginit_Arrow is indeed also defined in gtk2hs.o It is defined there because it is defined in gtk/misc/Arrow.o (in the buid tree). Itis defined there because Arrow is the name of the module and that symbol refers to the module initialisation function (or something like that, perhaps it's a module dependancy marker symbol). What seems to be happening is that the Arrow module in gtk2hs is clashing with the Arrow module in the lang package. As far as I can tell this all looks perfectly normal, so why don't we this kind of problem all the time? What's special about Arrow? How does it get resolved in the libHS*.a case? How does the system linker resolve the ambiguity when ghci's linker cannot? Duncan