[Bug ipa/109185] New: ICE in get_partitioning_class, at symtab.cc:2096

[Bug ipa/109185] New: ICE in get_partitioning_class, at symtab.cc:2096

[asolokha at gmx dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109185

            Bug ID: 109185
           Summary: ICE in get_partitioning_class, at symtab.cc:2096
           Product: gcc
           Version: 13.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code, lto
          Severity: normal
          Priority: P3
         Component: ipa
          Assignee: unassigned at gcc dot gnu.org
          Reporter: asolokha at gmx dot com
                CC: marxin at gcc dot gnu.org
  Target Milestone: ---

gcc 13.0.1 20230312 snapshot (g:f23dc726875c26f2c38dfded453aa9beba0b9be9) ICEs
when compiling the following testcase, reduced from
test/SemaTemplate/instantiate-static-local.cpp from the clang 15 test suite, w/
-flto:

namespace use_after_instantiation {
  template<int &R> struct A { static constexpr int &value = R; };

  template<typename = void> auto S() {
    static int s;
    return A<s>{};
  }

  auto &s = decltype(S())::value;
}

% g++-13 -flto -c rls6o5bx.cpp
during IPA pass: modref
rls6o5bx.cpp:10:1: internal compiler error: in get_partitioning_class, at
symtab.cc:2096
   10 | }
      | ^
0x7a6b1d symtab_node::get_partitioning_class()
       
/var/tmp/portage/sys-devel/gcc-13.0.1_p20230312/work/gcc-13-20230312/gcc/symtab.cc:2096
0x105d777 lto_output_varpool_node
       
/var/tmp/portage/sys-devel/gcc-13.0.1_p20230312/work/gcc-13-20230312/gcc/lto-cgraph.cc:631
0x105d777 output_symtab()
       
/var/tmp/portage/sys-devel/gcc-13.0.1_p20230312/work/gcc-13-20230312/gcc/lto-cgraph.cc:999
0x1074fdc lto_output()
       
/var/tmp/portage/sys-devel/gcc-13.0.1_p20230312/work/gcc-13-20230312/gcc/lto-streamer-out.cc:2825
0x1103181 write_lto
       
/var/tmp/portage/sys-devel/gcc-13.0.1_p20230312/work/gcc-13-20230312/gcc/passes.cc:2784
0x1103181 ipa_write_summaries_1
       
/var/tmp/portage/sys-devel/gcc-13.0.1_p20230312/work/gcc-13-20230312/gcc/passes.cc:2848
0x1103181 ipa_write_summaries()
       
/var/tmp/portage/sys-devel/gcc-13.0.1_p20230312/work/gcc-13-20230312/gcc/passes.cc:2904
0xd3dd92 ipa_passes
       
/var/tmp/portage/sys-devel/gcc-13.0.1_p20230312/work/gcc-13-20230312/gcc/cgraphunit.cc:2250
0xd3dd92 symbol_table::compile()
       
/var/tmp/portage/sys-devel/gcc-13.0.1_p20230312/work/gcc-13-20230312/gcc/cgraphunit.cc:2323
0xd405e7 symbol_table::compile()
       
/var/tmp/portage/sys-devel/gcc-13.0.1_p20230312/work/gcc-13-20230312/gcc/cgraphunit.cc:2303
0xd405e7 symbol_table::finalize_compilation_unit()
       
/var/tmp/portage/sys-devel/gcc-13.0.1_p20230312/work/gcc-13-20230312/gcc/cgraphunit.cc:2575

[Bug c++/109185] ICE in get_partitioning_class, at symtab.cc:2096

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109185

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
             Status|UNCONFIRMED                 |NEW
           Keywords|lto                         |link-failure
   Last reconfirmed|                            |2023-03-18

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Confirmed. Also fails with linking this:
```
template<int &R> struct A { static constexpr int &value = R; };

template<typename = void>
auto S() {
  static int s;
  return A<s>{};
}

auto &s = decltype(S())::value;

int main(void)
{
        return s;
}

```

So a front-end issue. Most likely not marking S<void>::s as being used.
Note instead of `decltype(S())::value`, I do `S().value`; it works.

[Bug c++/109185] ICE in get_partitioning_class, at symtab.cc:2096

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109185

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         Resolution|---                         |DUPLICATE
             Status|NEW                         |RESOLVED

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
exact Dup of bug 95686.

*** This bug has been marked as a duplicate of bug 95686 ***