bounds error on sparc when compiling haddock

trying to build a binary ghc-7.1 under sparc solaris failed (late) as follows:

"inplace/bin/ghc-stage2"   -H32m -O -optc-mcpu=ultrasparc -opta-mcpu=ultrasparc -DNEW_GHC_LAYOUT   -hide-all-packages -i -iutils/haddock/src -iutils/haddock/dist/build -iutils/haddock/dist/build/autogen -Iutils/haddock/dist/build -Iutils/haddock/dist/build/autogen    -optP-DIN_GHC_TREE -optP-include -optPutils/haddock/dist/build/autogen/cabal_macros.h -package Cabal-1.10.0.0 -package array-0.3.0.2 -package base-4.3.0.0 -package containers-0.4.0.0 -package directory-1.1.0.0 -package filepath-1.2.0.0 -package ghc-7.0.0.20100924 -package pretty-1.0.1.2 -package xhtml-3000.2.0.1  -funbox-strict-fields -O2 -Wall -fwarn-tabs -XForeignFunctionInterface -XCPP -XPatternGuards -XDeriveDataTypeable -XScopedTypeVariables -XMagicHash -no-user-package-conf -rtsopts     -odir utils/haddock/dist/build -hidir utils/haddock/dist/build -stubdir utils/haddock/dist/build -hisuf hi -osuf  o -hcsuf hc -c utils/haddock/src/Haddock/GhcUtils.hs -o utils/haddock/dist/build/Haddock/GhcUtils.o
ghc-stage2: panic! (the 'impossible' happened)
  (GHC version 7.0.0.20100924 for sparc-sun-solaris2):
        System.Event.Array.unsafeWrite': bounds error, index 1, capacity 1

Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug

gmake[1]: *** [utils/haddock/dist/build/Haddock/GhcUtils.o] Error 1
gmake: *** [all] Error 2

Trac metadata

Trac field	Value
Version	7.1
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
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