potential linking issue with Xcode-4.2 on Lion

[Adam Mercer]

Hi

I testing some software I maintain using the recently release
Xcode-4.2 on Mac OS X 10.7.2, and am running into the follow error
during link:

/bin/sh ../../../libtool  --tag=CC   --mode=link gcc -std=gnu99  -g
-O2 -g3 -O4 -Wall -W -Wmissing-prototypes -Wstrict-prototypes -Wshadow
-Wpointer-arith -Wcast-qual -Wcast-align -Wwrite-strings -fno-common
-Wnested-externs -Wno-format-zero-length -fno-strict-aliasing -Werror
-mmacosx-version-min=10.4 -version-info 0:0:0  -o liblalsupport.la
-rpath /opt/lscsoft/lal/lib Audio.lo ConfigFile.lo FileIO.lo
LALCache.lo LALInitBarycenter.lo LALMath3DPlot.lo LALMathNDPlot.lo
LogPrintf.lo PrintFrequencySeries.lo PrintTimeSeries.lo PrintVector.lo
ReadFiltersFile.lo ReadFrequencySeries.lo ReadTimeSeries.lo
ReadNoiseSpectrum.lo SegmentsIO.lo StreamSeriesInput.lo
StreamSeriesOutput.lo StreamSequenceInput.lo StreamGridInput.lo
StreamGridOutput.lo StreamVectorInput.lo StreamVectorSequenceInput.lo
UserInput.lo getopt.lo getopt1.lo -lz -lfftw3 -lfftw3f -lgsl
-lgslcblas -lm  -L/opt/local/lib -lgsl -lgslcblas -lm
-L/opt/local/lib -lfftw3 -lfftw3f -lm
libtool: link: gcc -std=gnu99 -dynamiclib -Wl,-undefined
-Wl,dynamic_lookup -o .libs/liblalsupport.0.dylib  .libs/Audio.o
.libs/ConfigFile.o .libs/FileIO.o .libs/LALCache.o
.libs/LALInitBarycenter.o .libs/LALMath3DPlot.o .libs/LALMathNDPlot.o
.libs/LogPrintf.o .libs/PrintFrequencySeries.o .libs/PrintTimeSeries.o
.libs/PrintVector.o .libs/ReadFiltersFile.o
.libs/ReadFrequencySeries.o .libs/ReadTimeSeries.o
.libs/ReadNoiseSpectrum.o .libs/SegmentsIO.o .libs/StreamSeriesInput.o
.libs/StreamSeriesOutput.o .libs/StreamSequenceInput.o
.libs/StreamGridInput.o .libs/StreamGridOutput.o
.libs/StreamVectorInput.o .libs/StreamVectorSequenceInput.o
.libs/UserInput.o .libs/getopt.o .libs/getopt1.o   -lz
-L/opt/local/lib /opt/local/lib/libgsl.dylib
/opt/local/lib/libgslcblas.dylib /opt/local/lib/libfftw3.dylib
/opt/local/lib/libfftw3f.dylib -lm  -O2 -O4 -mmacosx-version-min=10.4
 -install_name  /opt/lscsoft/lal/lib/liblalsupport.0.dylib
-compatibility_version 1 -current_version 1.0 -Wl,-single_module
ld: in .libs/Audio.o, could not parse object file .libs/Audio.o:
Malformed metadata record for architecture x86_64

the compiler being used is:

$ gcc --version
i686-apple-darwin11-llvm-gcc-4.2 (GCC) 4.2.1 (Based on Apple Inc.
build 5658) (LLVM build 2336.1.00)
Copyright (C) 2007 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

$

A brief Googling on the error suggests configuring with the
--build=x86_64 option, this allows the build to proceed a little
further but then another source files fails to link with the same
error.

Could this potentially be some kind of libtool issue, i.e. it not
being passed the appropriate options, or not knowing about this
compiler.

Any suggestions on how to debug this further?

Cheers

Adam