RFC: Move .shstrtab to end of section list

[Nick Clifton]

Hi Guys,

  I am planning on applying the attached patch to move the .shstrtab
  section to the end of the section list, but I wanted to seek people's
  opinions first.

  The problem being addressed is that, with the 2.27 release, section
  entries in the ELF section header are no longer ordered by increasing
  section offset.  Instead the .shstrtab section will often be placed
  earlier in the section table, despite coming at almost the very end of
  the file.  (The reason for this change is that because of possible
  section compression the name of some sections is not known until their
  contents are fully set, which happens quite late in the linking
  process, long after section numbers are assigned).

  The ELF standard does not require monotonically increasing section
  offsets in the section header, but there are other tools that rely
  upon this property (eg prelink, dwz).  Plus scanning ELF sections is
  already hard enough without having to allow for out of order section
  headers.

  So the patch makes a small change (that was actually created by Jakub
  Jelinek, not me) to the bfd/elf.c:assign_section_numbers() function.
  It moves the placement of the .shstrtab section to after the .symtab
  and .strtab sections, corresponding with how the file offsets for
  these sections will be organized later on.  This is a very small
  change.  The bulk of the patch is made up of fixes to the testsuites
  to allow for the new section ordering.

  I have tested lots of targets, and as far as I can tell the patch does
  not break anything, but I would be interested in hearing other
  people's opinions before I apply the patch.
  
Cheers
  Nick

bfd/ChangeLog

  * elf.c (assign_section_numbers): Assign number for the .shstrtab
  section after the symbol table and string table sections.

binutils/ChangeLog

  * testsuite/binutils-all/readelf.s: Adjust expected ordering of
  sections.
  * testsuite/binutils-all/readelf.s-64: Likewise.

gas/ChangeLog

  * testsuite/gas/i386/ilp32/x86-64-unwind.d: Adjust expected ordering
  of sections.
  * testsuite/gas/i386/x86-64-unwind.d: Likewise.
  * testsuite/gas/ia64/alias-ilp32.d: Likewise.
  * testsuite/gas/ia64/alias.d: Likewise.
  * testsuite/gas/ia64/group-1.d: Likewise.
  * testsuite/gas/ia64/group-2.d: Likewise.
  * testsuite/gas/ia64/secname-ilp32.d: Likewise.
  * testsuite/gas/ia64/secname.d: Likewise.
  * testsuite/gas/ia64/unwind-ilp32.d: Likewise.
  * testsuite/gas/ia64/unwind.d: Likewise.
  * testsuite/gas/ia64/xdata-ilp32.d: Likewise.
  * testsuite/gas/ia64/xdata.d: Likewise.
  * testsuite/gas/mmix/bspec-1.d: Likewise.
  * testsuite/gas/mmix/bspec-2.d: Likewise.
  * testsuite/gas/mmix/byte-1.d: Likewise.
  * testsuite/gas/mmix/loc-1.d: Likewise.
  * testsuite/gas/mmix/loc-2.d: Likewise.
  * testsuite/gas/mmix/loc-3.d: Likewise.
  * testsuite/gas/mmix/loc-4.d: Likewise.
  * testsuite/gas/mmix/loc-5.d: Likewise.
  * testsuite/gas/tic6x/scomm-directive-4.d: Likewise.

ld/ChangeLog

  * testsuite/ld-alpha/tlsbin.rd: Adjust expected ordering of sections.
  * testsuite/ld-alpha/tlsbinr.rd: Likewise.
  * testsuite/ld-alpha/tlspic.rd: Likewise.
  * testsuite/ld-cris/libdso-2.d: Likewise.
  * testsuite/ld-i386/nogot1.d: Likewise.
  * testsuite/ld-i386/pr12718.d: Likewise.
  * testsuite/ld-i386/pr12921.d: Likewise.
  * testsuite/ld-i386/tlsbin-nacl.rd: Likewise.
  * testsuite/ld-i386/tlsbin.rd: Likewise.
  * testsuite/ld-i386/tlsbin2-nacl.rd: Likewise.
  * testsuite/ld-i386/tlsbin2.rd: Likewise.
  * testsuite/ld-i386/tlsbindesc-nacl.rd: Likewise.
  * testsuite/ld-i386/tlsbindesc.rd: Likewise.
  * testsuite/ld-i386/tlsdesc-nacl.rd: Likewise.
  * testsuite/ld-i386/tlsdesc.rd: Likewise.
  * testsuite/ld-i386/tlsgdesc-nacl.rd: Likewise.
  * testsuite/ld-i386/tlsgdesc.rd: Likewise.
  * testsuite/ld-i386/tlsnopic-nacl.rd: Likewise.
  * testsuite/ld-i386/tlsnopic.rd: Likewise.
  * testsuite/ld-i386/tlspic-nacl.rd: Likewise.
  * testsuite/ld-i386/tlspic.rd: Likewise.
  * testsuite/ld-i386/tlspic2-nacl.rd: Likewise.
  * testsuite/ld-i386/tlspic2.rd: Likewise.
  * testsuite/ld-ia64/tlsbin.rd: Likewise.
  * testsuite/ld-ia64/tlspic.rd: Likewise.
  * testsuite/ld-mips-elf/attr-gnu-4-10.d: Likewise.
  * testsuite/ld-mips-elf/attr-gnu-4-50.d: Likewise.
  * testsuite/ld-mips-elf/attr-gnu-4-60.d: Likewise.
  * testsuite/ld-mips-elf/attr-gnu-4-70.d: Likewise.
  * testsuite/ld-mmix/bspec1.d: Likewise.
  * testsuite/ld-mmix/bspec2.d: Likewise.
  * testsuite/ld-mmix/local1.d: Likewise.
  * testsuite/ld-mmix/local3.d: Likewise.
  * testsuite/ld-mmix/local5.d: Likewise.
  * testsuite/ld-mmix/local7.d: Likewise.
  * testsuite/ld-mmix/undef-3.d: Likewise.
  * testsuite/ld-powerpc/tlsexe.r: Likewise.
  * testsuite/ld-powerpc/tlsexe32.r: Likewise.
  * testsuite/ld-powerpc/tlsexetoc.r: Likewise.
  * testsuite/ld-powerpc/tlsso.r: Likewise.
  * testsuite/ld-powerpc/tlsso32.r: Likewise.
  * testsuite/ld-powerpc/tlstocso.r: Likewise.
  * testsuite/ld-s390/tlsbin.rd: Likewise.
  * testsuite/ld-s390/tlsbin_64.rd: Likewise.
  * testsuite/ld-s390/tlspic.rd: Likewise.
  * testsuite/ld-s390/tlspic_64.rd: Likewise.
  * testsuite/ld-sh/sh64/crange1.rd: Likewise.
  * testsuite/ld-sh/sh64/crange2.rd: Likewise.
  * testsuite/ld-sh/sh64/crange3-cmpct.rd: Likewise.
  * testsuite/ld-sh/sh64/crange3-media.rd: Likewise.
  * testsuite/ld-sh/sh64/crange3.rd: Likewise.
  * testsuite/ld-sh/sh64/crangerel1.rd: Likewise.
  * testsuite/ld-sh/sh64/crangerel2.rd: Likewise.
  * testsuite/ld-sh/tlsbin-2.d: Likewise.
  * testsuite/ld-sh/tlspic-2.d: Likewise.
  * testsuite/ld-sparc/gotop32.rd: Likewise.
  * testsuite/ld-sparc/gotop64.rd: Likewise.
  * testsuite/ld-sparc/tlssunbin32.rd: Likewise.
  * testsuite/ld-sparc/tlssunbin64.rd: Likewise.
  * testsuite/ld-sparc/tlssunnopic32.rd: Likewise.
  * testsuite/ld-sparc/tlssunnopic64.rd: Likewise.
  * testsuite/ld-sparc/tlssunpic32.rd: Likewise.
  * testsuite/ld-sparc/tlssunpic64.rd: Likewise.
  * testsuite/ld-tic6x/common.d: Likewise.
  * testsuite/ld-tic6x/shlib-1.rd: Likewise.
  * testsuite/ld-tic6x/shlib-1b.rd: Likewise.
  * testsuite/ld-tic6x/shlib-1r.rd: Likewise.
  * testsuite/ld-tic6x/shlib-1rb.rd: Likewise.
  * testsuite/ld-tic6x/shlib-app-1.rd: Likewise.
  * testsuite/ld-tic6x/shlib-app-1b.rd: Likewise.
  * testsuite/ld-tic6x/shlib-app-1r.rd: Likewise.
  * testsuite/ld-tic6x/shlib-app-1rb.rd: Likewise.
  * testsuite/ld-tic6x/shlib-noindex.rd: Likewise.
  * testsuite/ld-tic6x/static-app-1.rd: Likewise.
  * testsuite/ld-tic6x/static-app-1b.rd: Likewise.
  * testsuite/ld-tic6x/static-app-1r.rd: Likewise.
  * testsuite/ld-tic6x/static-app-1rb.rd: Likewise.
  * testsuite/ld-x86-64/ilp32-4-nacl.d: Likewise.
  * testsuite/ld-x86-64/ilp32-4.d: Likewise.
  * testsuite/ld-x86-64/nogot1.d: Likewise.
  * testsuite/ld-x86-64/pr12718.d: Likewise.
  * testsuite/ld-x86-64/pr12921.d: Likewise.
  * testsuite/ld-x86-64/split-by-file-nacl.rd: Likewise.
  * testsuite/ld-x86-64/split-by-file.rd: Likewise.
  * testsuite/ld-x86-64/tlsbin-nacl.rd: Likewise.
  * testsuite/ld-x86-64/tlsbin.rd: Likewise.
  * testsuite/ld-x86-64/tlsbin2-nacl.rd: Likewise.
  * testsuite/ld-x86-64/tlsbin2.rd: Likewise.
  * testsuite/ld-x86-64/tlsbindesc-nacl.rd: Likewise.
  * testsuite/ld-x86-64/tlsbindesc.rd: Likewise.
  * testsuite/ld-x86-64/tlsdesc-nacl.rd: Likewise.
  * testsuite/ld-x86-64/tlsdesc.rd: Likewise.
  * testsuite/ld-x86-64/tlsgdesc-nacl.rd: Likewise.
  * testsuite/ld-x86-64/tlsgdesc.rd: Likewise.
  * testsuite/ld-x86-64/tlspic-nacl.rd: Likewise.
  * testsuite/ld-x86-64/tlspic.rd: Likewise.
  * testsuite/ld-x86-64/tlspic2-nacl.rd: Likewise.
  * testsuite/ld-x86-64/tlspic2.rd: Likewise.
  * testsuite/ld-xtensa/tlsbin.rd: Likewise.
  * testsuite/ld-xtensa/tlspic.rd: Likewise.
  
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