On 18 Feb 2015 14:24, H.J. Lu wrote:
> On Wed, Feb 18, 2015 at 2:21 PM, Mike Frysinger wrote:
> > i think we already have the reports: multiple people don't think it should be
> > (1) x86-specific or (2) required.  don't get me wrong -- i think having support
> > like this is great.  that doesn't mean we should be forcing it.
> 
> Please file a bug report with a testcase.

this is getting kafka-esque.  you yourself stated:
  On Linux/x86, zlib is required for assembler.  At least, you should issue an 
  error when --without-libz is used in binutils for Linux/x86 target.
that should not be the case.  making someone open a bug report so you can close 
it with "fixed" and a patch is wasting time.  just fix it now.

all that said, if we look at your actual commit (89e7505fcde4bd83948f559f429a0):
gas/config/tc-i386.c:
  +#ifdef TE_LINUX
  +/* Default to compress debug sections for Linux.  */
  +int flag_compress_debug = 1;
  +#endif

and we look at where that flag is used:
gas/as.c:
  ...
    case OPTION_COMPRESS_DEBUG:
  #ifdef HAVE_ZLIB_H
      flag_compress_debug = 1;
  #else
      as_warn (_("cannot compress debug sections (zlib not installed)"));
  #endif /* HAVE_ZLIB_H */
      break;

    case OPTION_NOCOMPRESS_DEBUG:
      flag_compress_debug = 0;
      break;
  ...

gas/write.c:
  void
  write_object_file (void)
  {
  ...
    if (flag_compress_debug)
      bfd_map_over_sections (stdoutput, compress_debug, (char *) 0);
  ...
  static void
  compress_debug (bfd *abfd, asection *sec, void *xxx ATTRIBUTE_UNUSED)
  {
  ...
    strm = compress_init ();
    if (strm == NULL)
      return;

it turns out the current code does *not* require zlib.  as long as that does not 
change (either issuing a warning or throwing an error), i see no reason why we 
need or should make zlib a requirement in binutils, regardless of target.
-mike