[Bug other/54586] New: Help diagnosing error: Link tests are not allowed after GCC_NO_EXECUTABLES

[baker at usgs dot gov]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54586

             Bug #: 54586
           Summary: Help diagnosing error: Link tests are not allowed
                    after GCC_NO_EXECUTABLES
    Classification: Unclassified
           Product: gcc
           Version: 4.7.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: other
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: baker@usgs.gov


This is not a bug report, but a feature request.

I have been struggling with building GCC cross compilers.  When I unexpectedly
encounter error: Link tests are not allowed after GCC_NO_EXECUTABLES, what I
really need to do is find out which previous configure step broke and set
gcc_no_link=yes.  The "Link tests..." error is a consequence of the true error,
which is not identified as having set gcc_no_link=yes.

I have taken to hand editing configure files when this happens and inserting my
own diagnostic output when either gcc_no_link=no or gcc_no_link=yes is
executed, e.g., in libiberty/configure:

# FIXME: Cleanup?
if { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_link\""; } >&5
  (eval $ac_link) 2>&5
  ac_status=$?
  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
  test $ac_status = 0; }; then :

  $as_echo "$as_me:${as_lineno-$LINENO}: ---> gcc_no_link=no" >&5

  gcc_no_link=no
else

  $as_echo "$as_me:${as_lineno-$LINENO}: ---> gcc_no_link=yes" >&5

  gcc_no_link=yes
fi

It would be really useful if all GCC configure files would emit such a message,
at least when setting gcc_no_link=yes.  It would make it a lot easier to
trouble shoot "Link tests..." errors.