[Bug tree-optimization/50602] New: ICE in tree_nrv, at tree-nrv.c:155 during large LTO build

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

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50602

             Bug #: 50602
           Summary: ICE in tree_nrv, at tree-nrv.c:155 during large LTO
                    build
    Classification: Unclassified
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: andi-gcc@firstfloor.org


I get this at the end of a large 32bit LTO build. Cannot give you a small test
case unless you want the full builddir. Bisect is difficult because
the build relies on some recent other fixes.

But I have a core file:

#6  0x0000000000b47eb4 in fancy_abort (file=Unhandled dwarf expression opcode
0xf3
) at ../../gcc/gcc/diagnostic.c:893
#7  0x000000000075ac05 in tree_nrv () at ../../gcc/gcc/tree-nrv.c:155
#8  0x000000000068d7ab in execute_one_pass (pass=0x10a9ac0) at
../../gcc/gcc/passes.c:2064
#9  0x000000000068dae5 in execute_pass_list (pass=0x10a9ac0) at
../../gcc/gcc/passes.c:2119
#10 0x000000000075df39 in tree_rest_of_compilation (fndecl=0x2b84d3ea6900) at
../../gcc/gcc/tree-optimize.c:420
#11 0x000000000051ad36 in cgraph_expand_function (node=0x2b84e28a7360) at
../../gcc/gcc/cgraphunit.c:1805
#12 0x000000000051c612 in cgraph_output_in_order () at
../../gcc/gcc/cgraphunit.c:1962
#13 cgraph_optimize () at ../../gcc/gcc/cgraphunit.c:2136
#14 0x00000000004cb7c5 in lto_main () at ../../gcc/gcc/lto/lto.c:2872


...

#7  0x000000000075ac05 in tree_nrv () at ../../gcc/gcc/tree-nrv.c:155
155                     gcc_assert (ret_val == result);

(gdb) p ret_val
$3 = (tree_node *) 0x0

(gdb) pt result
type = union tree_node {
    tree_base base;
    tree_typed typed;
    tree_common common;
    tree_int_cst int_cst;
    tree_real_cst real_cst;
    tree_fixed_cst fixed_cst;
    tree_vector vector;
    tree_string string;
    tree_complex complex;
    tree_identifier identifier;
    tree_decl_minimal decl_minimal;
    tree_decl_common decl_common;
    tree_decl_with_rtl decl_with_rtl;
    tree_decl_non_common decl_non_common;
    tree_parm_decl parm_decl;
    tree_decl_with_vis decl_with_vis;
    tree_var_decl var_decl;
    tree_field_decl field_decl;
    tree_label_decl label_decl;
    tree_result_decl result_decl;
    tree_const_decl const_decl;
    tree_type_decl type_decl;
    tree_function_decl function_decl;
    tree_translation_unit_decl translation_unit_decl;
    tree_type_common type_common;
    tree_type_with_lang_specific type_with_lang_specific;
    tree_type_non_common type_non_common;
    tree_list list;
    tree_vec vec;
    tree_exp exp;
    tree_ssa_name ssa_name;
    tree_block block;
    tree_binfo binfo;
    tree_statement_list stmt_list;
    tree_constructor constructor;
    tree_omp_clause omp_clause;
    tree_optimization_option optimization;
    tree_target_option target_option;
} *