[Haskell-cafe] Symbol collisions with -fhpc

Does anyone know what causes these? This used to work, like, a month ago. It builds fine without the -fhpc. $ ghc -fhpc -O2 -odir /tmp -hidir /tmp --make -o bin/spline3 src/*.hs [ 1 of 17] Compiling ScaleFactor ( src/ScaleFactor.hs, /tmp/ScaleFactor.o ) ... [13 of 17] Compiling Tetrahedron ( src/Tetrahedron.hs, /tmp/Tetrahedron.o ) /tmp/ghc29431_0/ghc29431_0.s: Assembler messages: /tmp/ghc29431_0/ghc29431_0.s:48147:0: Error: symbol `d2ln_info' is already defined /tmp/ghc29431_0/ghc29431_0.s:48158:0: Error: symbol `d2ll_info' is already defined /tmp/ghc29431_0/ghc29431_0.s:48169:0: Error: symbol `d2lh_info' is already defined