[Bug debug/46123] [4.5/4.6 Regression] ICE: in output_aranges, at dwarf2out.c:11531 with -feliminate-dwarf2-dups -g

["davek at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46123

Dave Korn <davek at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |davek at gcc dot gnu.org

--- Comment #9 from Dave Korn <davek at gcc dot gnu.org> 2010-12-04 06:26:55 UTC ---
The testcase is failing for me on i686-pc-cygwin:

spawn /gnu/gcc/obj-pr40125/gcc/testsuite/g++/../../g++
-B/gnu/gcc/obj-pr40125/gcc/testsuite/g++/../../
/gnu/gcc/gcc-patched/gcc/testsuite/g++.dg/debug/pr46123.C -nostdinc++
-I/gnu/gcc/obj-pr40125/i686-pc-cygwin/libstdc++-v3/include/i686-pc-cygwin
-I/gnu/gcc/obj-pr40125/i686-pc-cygwin/libstdc++-v3/include
-I/gnu/gcc/gcc-patched/libstdc++-v3/libsupc++
-I/gnu/gcc/gcc-patched/libstdc++-v3/include/backward
-I/gnu/gcc/gcc-patched/libstdc++-v3/testsuite/util -fmessage-length=0 -gdwarf-2
-g -feliminate-dwarf2-dups -S -o pr46123.s 
/gnu/gcc/gcc-patched/gcc/testsuite/g++.dg/debug/pr46123.C:47:1: internal
compiler error: in output_aranges, at dwarf2out.c:11678

 It happens here, 

(gdb) bt
#0  0x007c7c70 in fancy_abort (
    file=0xe22afc "/gnu/gcc/gcc-patched/gcc/dwarf2out.c", line=11678,
    function=0xe284b4 "output_aranges")
    at /gnu/gcc/gcc-patched/gcc/diagnostic.c:101
#1  0x0066b9c1 in dwarf2out_finish (
    filename=0x59bccaa
"/gnu/gcc/gcc-patched/gcc/testsuite/g++.dg/debug/pr46123.
C") at /gnu/gcc/gcc-patched/gcc/dwarf2out.c:1109

... in dwarf2out.c, where output_aranges() has been inlined into
dwarf2out_finish:

  /* It is necessary not to output these entries if the sections were
     not used; if the sections were not used, the length will be 0 and
     the address may end up as 0 if the section is discarded by ld
     --gc-sections, leaving an invalid (0, 0) entry that can be
     confused with the terminator.  */
  if (text_section_used)
    {
      dw2_asm_output_addr (DWARF2_ADDR_SIZE, text_section_label, "Address");
      dw2_asm_output_delta (DWARF2_ADDR_SIZE, text_end_label,
                text_section_label, "Length");
    }
  if (cold_text_section_used)
    {
      dw2_asm_output_addr (DWARF2_ADDR_SIZE, cold_text_section_label,
               "Address");
      dw2_asm_output_delta (DWARF2_ADDR_SIZE, cold_end_label,
                cold_text_section_label, "Length");
    }

  for (i = 0; i < arange_table_in_use; i++)
    {
      dw_die_ref die = arange_table[i];

      /* We shouldn't see aranges for DIEs outside of the main CU.  */
      gcc_assert (die->die_mark);

  This assertion triggers on the second address range in the table:

(gdb) p arange_table[0][0]
$2 = {die_id = {die_symbol = 0x0, die_type_node = 0x0},
  die_attr = 0x7ff01400, die_parent = 0x7feb1980, die_child = 0x7feb1b00,
  die_sib = 0x7feb19e0, die_definition = 0x0, die_offset = 98,
  die_abbrev = 4, die_mark = 0, die_perennial_p = 0, decl_id = 1705,
  die_tag = DW_TAG_subprogram}
(gdb) p arange_table[1][0]
$3 = {die_id = {die_symbol = 0x0, die_type_node = 0x0},
  die_attr = 0x7ff816c0, die_parent = 0x7feb0360, die_child = 0x7feb1e00,
  die_sib = 0x7feb2340, die_definition = 0x0, die_offset = 78,
  die_abbrev = 9, die_mark = 1, die_perennial_p = 0, decl_id = 1697,
  die_tag = DW_TAG_subprogram}
(gdb) p arange_table[2]
$4 = (dw_die_ref) 0x0
(gdb)

  Any ideas what this could mean?