* readelf.c (warn): New function - like elfcomm.c version but only
produces output if warnings are enabled.
(struct options): Add --lint and --enable-checks.
(usage): Add entry for --lint.
(parse_args): Handle -L. If checks are enabled but no dumps have
been selected then enable all dumps.
(process_section_headers): Replace long if-then-else sequence with
a switch. Add warning messages for empty SHT_REL, SHT_RELA and
SHT_PROGBITS sections.
(process_file): Do not complain if the file is an archive and lint
mode has been enabled.
* elfcomm.c (error): Make the function weak.
(warn): Likewise.
* NEWS: Mention the new feature.
* doc/binutils.texi: Document the new feature.
* dwarf.h (report_leb_status): Add file name and line number
parameters. Include them in the diagnostic output.
(READ_ULEB): Pass file and line number to report_leb_status.
(READ_SLEB): Likewise.
* dwarf.c (read_and_print_leb128): Pass file and line number to
report_leb_status.
* testsuite/binutils-all/readelf.exp: Add test of new feature.
* testsuite/binutils-all/zero-sec.s: New test source file.
* testsuite/binutils-all/zero-sec.r: Expected output from new
test.