[Bug debug/81936] ICE in dwarf2out_die_ref_for_decl, at dwarf2out.c:5543

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81936

--- Comment #3 from Tom de Vries <vries at gcc dot gnu.org> ---
ICE is due to assert:
...
    at gcc/dwarf2out.c:5542
5542      gcc_assert (die->die_tag == DW_TAG_compile_unit
5543                  && die->die_id.die_symbol != NULL);
...

The assert triggers because die->die_id.die_symbol is NULL:
...
(gdb) p die->die_tag
$3 = DW_TAG_compile_unit
(gdb) p die->die_id.die_symbol
$4 = 0x0
...

If we go up we see we're trying to find a die_ref for 'expr':
...
(gdb) up
#7  0x0000000000b9d804 in lto_write_tree_1 (ob=0x2771d30, expr=0x7ffff7521180,
ref_p=Unhandled dwarf expression opcode 0xf3)
    at gcc/lto-streamer-out.c:422
422               && debug_hooks->die_ref_for_decl (expr, &sym, &off))
...

and expr is:
...
(gdb) call debug_generic_expr (expr)
.omp_data_i
...