Problem building on host machine when trying to cross-compile an unregistered build

[jb162 at brighton.ac.uk]

Hi, host machine is Linux i386 and the target is NetBSD alpha, ghc
6.8.2. With the help of the list the first part (on the target) is done
and I'm building the compiler on the host -- when building rts I get 

"cc1: error: unrecognized command line option "-mieee"

What's this about? (I notice a couple of seemingly ignorable warnings in
the following, about missing gmpbuild and libHSrts.a. Is that relevant?)
Thanks.

jim at mowa624-jb162:~/ghc-6.8.2/compiler$ cd ../rts && make boot && make
gcc -E  -undef -traditional -P \
                -DIMPORT_DIR='"/home/jim/ghc-6.8.2/libraries/rts"' \
                -DLIB_DIR='"/home/jim/ghc-6.8.2/libraries/rts"' \

-DINCLUDE_DIR='"/home/jim/ghc-6.8.2/libraries/rts/include"' \
                -DDATA_DIR='"/home/jim/ghc-6.8.2/libraries/rts"' \
                -DHTML_DIR='"/home/jim/ghc-6.8.2/libraries/rts/html"' \

-DHADDOCK_IFACE='"/home/jim/ghc-6.8.2/libraries/rts/html/rts.haddock"' \
                -DFPTOOLS_TOP_ABS='"/home/jim/ghc-6.8.2"' \
                -x c -DGMP_INCLUDE_DIRS='' -DGMP_LIB_DIRS=''
-I../includes -Iinclude -DPACKAGE=rts -DVERSION=
-DPKG_LIBDIR='"/usr/local/lib/ghc-6.8.2"'
-DPKG_DATADIR='"/usr/local/share/ghc-6.8.2"' package.conf.in | \
        grep -v '^#pragma GCC' | \
        sed -e 's/""//g' -e 's/:[       ]*,/: /g' >package.conf.inplace
../utils/ghc-pkg/ghc-pkg-inplace update - --force-files
<package.conf.inplace
Reading package info from stdin ... done.
/home/jim/ghc-6.8.2/gmp/gmpbuild doesn't exist or isn't a directory
(ignoring)
cannot find libHSrts.a on library path (ignoring)
Saving old package config file... done.
Writing new package config file... done.
../utils/mkdependC/mkdependC -f .depend -I. -I../includes -DPROFILING
-DTHREADED_RTS -DDEBUG -Ihooks -Iparallel -Ism -Iposix -I../includes
-s debug -- -O -Wall -W -Wstrict-prototypes  -Wmissing-prototypes
-Wmissing-declarations -Winline -Waggregate-return -I../includes -I.
-Iparallel -Ism -DCOMPILING_RTS -fomit-frame-pointer -DNOSMP
-I../gmp/gmpbuild -fno-strict-aliasing    -- Adjustor.c Arena.c
Capability.c ClosureFlags.c Disassembler.c FrontPanel.c Hash.c Hpc.c
HsFFI.c Interpreter.c LdvProfile.c Linker.c Main.c Papi.c Printer.c
ProfHeap.c Profiling.c Proftimer.c RaiseAsync.c RetainerProfile.c
RetainerSet.c RtsAPI.c RtsFlags.c RtsMessages.c RtsStartup.c RtsUtils.c
STM.c Sanity.c Schedule.c Sparks.c Stable.c Stats.c StgCRun.c
StgPrimFloat.c Task.c ThreadLabels.c ThreadPaused.c Threads.c Ticky.c
Timer.c Trace.c Typeable.c Weak.c hooks/FlagDefaults.c
hooks/InitEachPE.c hooks/MallocFail.c hooks/OnExit.c hooks/OutOfHeap.c
hooks/RtsOpts.c hooks/ShutdownEachPEHook.c hooks/StackOverflow.c
parallel/0Hash.c parallel/0Unpack.c parallel/Dist.c parallel/Global.c
parallel/GranSim.c parallel/HLComms.c parallel/LLComms.c parallel/Pack.c
parallel/ParInit.c parallel/ParTicky.c parallel/Parallel.c
parallel/ParallelDebug.c parallel/RBH.c posix/FileLock.c posix/GetTime.c
posix/Itimer.c posix/OSMem.c posix/OSThreads.c posix/Select.c
posix/Signals.c sm/BlockAlloc.c sm/Compact.c sm/Evac.c sm/GC.c
sm/GCUtils.c sm/MBlock.c sm/MarkWeak.c sm/Scav.c sm/Storage.c 
../compiler/ghc-inplace -optc-O -optc-Wall -optc-W
-optc-Wstrict-prototypes -optc-Wmissing-prototypes
-optc-Wmissing-declarations -optc-Winline -optc-Waggregate-return
-optc-I../includes -optc-I. -optc-Iparallel -optc-Ism
-optc-DCOMPILING_RTS -optc-fomit-frame-pointer -optc-DNOSMP
-optc-I../gmp/gmpbuild -optc-fno-strict-aliasing -H16m -O -H32m
-keep-hc-files -package-name rts -optc-DNOSMP -static -I../gmp/gmpbuild
-I. -#include HCIncludes.h -dcmm-lint     -c Adjustor.c -o Adjustor.o
cc1: error: unrecognized command line option "-mieee"
make: *** [Adjustor.o] Error 1