gl_IGNORE_UNUSED_LIBRARIES sets --as-needed on HP-UX but should not

[Bob Proulx]

For past reference see:

  http://lists.gnu.org/archive/html/bug-gnulib/2006-06/msg00119.html

While building coreutils on HP-UX 11.11 using the native hp c compiler
I noticed that gnulib's gl_IGNORE_UNUSED_LIBRARIES causes --as-needed
to be inadvertently used where it is not a valid option there.  It
does not actually break the coreutils build and is why the warnings it
produced went undetected.

The compile output produces this on HP-UX using the native compiler.

  cc  -g  --as-needed -o cp  cp.o copy.o cp-hash.o ../lib/libcoreutils.a  
../lib/libcoreutils.a   -lsec 
  cc: warning 422: Unknown option "-" ignored.
  cc: warning 422: Unknown option "a" ignored.
  cc: warning 422: Unknown option "-" ignored.
  cc: warning 422: Unknown option "-needed" ignored.
  cc: warning 401: -s and -g are mutually exclusive, -s ignored.

Here are the relevant (I think) snippets from config.log:

  configure:5625: cc -o conftest -g  -Wl,--as-needed  conftest.c  >&5
  /usr/ccs/bin/ld: Unrecognized argument: --as-needed
  /usr/ccs/bin/ld: Usage:  /usr/ccs/bin/ld [options] [flags] files
  configure:5631: $? = 1
  configure: failed program was:
  ...
  configure:5625: cc -o conftest -g  -Wl,-z,ignore  conftest.c  >&5
  /usr/ccs/bin/ld: Can't open ignore
  /usr/ccs/bin/ld: No such file or directory
  configure:5631: $? = 1
  configure: failed program was:
  ...
  configure:5625: cc -o conftest -g  --as-needed  conftest.c  >&5
  cc: warning 422: Unknown option "-" ignored.
  cc: warning 422: Unknown option "a" ignored.
  cc: warning 422: Unknown option "-" ignored.
  cc: warning 422: Unknown option "-needed" ignored.
  cc: warning 401: -s and -g are mutually exclusive, -s ignored.
  configure:5631: $? = 0
  configure:5638: test -z "$ac_c_werror_flag" || test ! -s conftest.err
  configure:5641: $? = 0
  configure:5648: test -s conftest
  configure:5651: $? = 0
  configure:5667: result: --as-needed

Should the stderr be captured and if non-zero in size also denote a
failure?

Thanks
Bob