[Bug c++/107542] New: ICE in spaceship_comp_cat, at cp/method.cc:1055

[Bug c++/107542] New: ICE in spaceship_comp_cat, at cp/method.cc:1055

[danakj at orodu dot net]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107542

            Bug ID: 107542
           Summary: ICE in spaceship_comp_cat, at cp/method.cc:1055
           Product: gcc
           Version: 12.2.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: danakj at orodu dot net
  Target Milestone: ---

Repro: https://godbolt.org/z/KPfsn8hPf

Reproduces in 12.2 and trunk on Godbolt.org.

Output:
<source>: In substitution of 'template<class T, class U>  requires  Ord<const
T*, const U*> constexpr auto operator<=>(const S<T>&, const S<U>&) [with T =
int; U = char]':
<source>:6:11:   required from here
<source>:6:11: internal compiler error: in spaceship_comp_cat, at
cp/method.cc:1055
    6 |     { lhs <=> rhs } -> std::same_as<std::strong_ordering>;
      |       ~~~~^~~~~~~
0x2393c6e internal_error(char const*, ...)
        ???:0
0xaa9b58 fancy_abort(char const*, int, char const*)
        ???:0
0xd4a507 cp_build_binary_op(op_location_t const&, tree_code, tree_node*,
tree_node*, int)
        ???:0
0xadb22c build_new_op(op_location_t const&, tree_code, int, tree_node*,
tree_node*, tree_node*, tree_node*, tree_node**, int)
        ???:0
0xd3b412 build_x_binary_op(op_location_t const&, tree_code, tree_node*,
tree_code, tree_node*, tree_code, tree_node*, tree_node**, int)
        ???:0
0xb25576 tsubst_requires_expr(tree_node*, tree_node*, int, tree_node*)
        ???:0
0xb27052 constraints_satisfied_p(tree_node*, tree_node*)
        ???:0
0xcdd84a fn_type_unification(tree_node*, tree_node*, tree_node*, tree_node*
const*, unsigned int, tree_node*, unification_kind_t, int, conversion**, bool,
bool)
        ???:0
0xadaefe build_new_op(op_location_t const&, tree_code, int, tree_node*,
tree_node*, tree_node*, tree_node*, tree_node**, int)
        ???:0
0xd3b412 build_x_binary_op(op_location_t const&, tree_code, tree_node*,
tree_code, tree_node*, tree_code, tree_node*, tree_node**, int)
        ???:0
0xb25576 tsubst_requires_expr(tree_node*, tree_node*, int, tree_node*)
        ???:0
0xb2715f evaluate_concept_check(tree_node*)
        ???:0
0xb18962 maybe_constant_value(tree_node*, tree_node*, bool)
        ???:0
0xcfdb3f finish_unary_op_expr(unsigned int, tree_code, cp_expr, int)
        ???:0
0xc872a7 c_parse_file()
        ???:0
0xdd0579 c_common_parse_file()
        ???:0
Please submit a full bug report, with preprocessed source (by using
-freport-bug).
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.

[Bug c++/107542] ICE in spaceship_comp_cat, at cp/method.cc:1055

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107542

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Created attachment 53840
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=53840&action=edit
testcase

Note please next time also attach the testcase (or put it inline) and not just
link against godbolt.

[Bug c++/107542] ICE in spaceship_comp_cat, at cp/method.cc:1055

[danakj at orodu dot net]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107542

--- Comment #2 from danakj at orodu dot net ---
The same thing works okay with operator== instead of operator<=>

https://godbolt.org/z/qnPx3bYT4

```
#include <compare>
#include <concepts>

template <class Lhs, class Rhs>
concept Ord = requires(const Lhs& lhs, const Rhs& rhs) {
    { lhs <=> rhs } -> std::same_as<std::strong_ordering>;
};

template <class Lhs, class Rhs>
concept Eq = requires(const Lhs& lhs, const Rhs& rhs) {
    { lhs == rhs } -> std::same_as<bool>;
};

template <class T>
struct S {
    T* p;
};

template <class T, class U>
    requires(Eq<const T*, const U*>)
bool operator==(const S<T>& l, const S<U>& r) {
    return l.p == r.p;
}

template <class T, class U>
    requires(Ord<const T*, const U*>)
constexpr inline auto operator<=>(const S<T>& l, const S<U>& r) noexcept {
    return l.p <=> r.p;
}

static_assert(Ord<S<int>, S<int>>);  // Works.
// static_assert(!Ord<S<int>, S<S<int>>>);  // ICE.

static_assert(Eq<S<int>, S<int>>);  // Works.
static_assert(!Eq<S<int>, S<char>>);  // Works.
```

[Bug c++/107542] ICE in spaceship_comp_cat, at cp/method.cc:1055

[danakj at orodu dot net]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107542

--- Comment #3 from danakj at orodu dot net ---
> Note please next time also attach the testcase (or put it inline) and not just link against godbolt.

Will do, thanks for attaching it for me.

[Bug c++/107542] ICE in spaceship_comp_cat, at cp/method.cc:1055

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107542

Martin Liška <marxin at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jason at gcc dot gnu.org,
                   |                            |marxin at gcc dot gnu.org
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2022-11-21
     Ever confirmed|0                           |1

--- Comment #4 from Martin Liška <marxin at gcc dot gnu.org> ---
Reduced test-case:

$ cat pr107542.ii
template <class Lhs, class Rhs>
concept Ord = requires(Lhs lhs, Rhs rhs) { lhs <=> rhs; };
template <class> struct S;
template <class T, class U>
  requires(Ord<T *, U *>)
auto operator<=>(T, U) {
  !Ord<int, S<int>>;
}

Note spaceship_comp_cat is called with:
optype=<error_mark 0x7ffff7621fa8>

[Bug c++/107542] ICE in spaceship_comp_cat, at cp/method.cc:1055

[ppalka at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107542

Patrick Palka <ppalka at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |ppalka at gcc dot gnu.org
             Status|NEW                         |ASSIGNED
           Assignee|unassigned at gcc dot gnu.org      |ppalka at gcc dot gnu.org

[Bug c++/107542] ICE in spaceship_comp_cat, at cp/method.cc:1055

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107542

--- Comment #5 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Patrick Palka <ppalka@gcc.gnu.org>:

https://gcc.gnu.org/g:000e9863120cbc75a0f8d497264519974c97669f

commit r13-4397-g000e9863120cbc75a0f8d497264519974c97669f
Author: Patrick Palka <ppalka@redhat.com>
Date:   Tue Nov 29 19:25:37 2022 -0500

    c++: ICE with <=> of incompatible pointers [PR107542]

    In a SFINAE context composite_pointer_type returns error_mark_node if
    the given pointer types are incompatible.  But the SPACESHIP_EXPR case
    of cp_build_binary_op wasn't prepared for this error_mark_node result,
    which led to an ICE (from spaceship_comp_cat) for the below testcase.
    (In a non-SFINAE context composite_pointer_type issues a permerror and
    returns cv void* in this case, so this ICE seems specific to SFINAE.)

            PR c++/107542

    gcc/cp/ChangeLog:

            * typeck.cc (cp_build_binary_op): In the SPACESHIP_EXPR case,
            handle an error_mark_node result type.

    gcc/testsuite/ChangeLog:

            * g++.dg/cpp2a/spaceship-sfinae2.C: New test.

[Bug c++/107542] ICE in spaceship_comp_cat, at cp/method.cc:1055

[ppalka at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107542

Patrick Palka <ppalka at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |12.3

--- Comment #6 from Patrick Palka <ppalka at gcc dot gnu.org> ---
Fixed on trunk so far.

[Bug c++/107542] ICE in spaceship_comp_cat, at cp/method.cc:1055

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107542

--- Comment #7 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-12 branch has been updated by Patrick Palka
<ppalka@gcc.gnu.org>:

https://gcc.gnu.org/g:37595f8354e3e48e4a1a94537f3d1ae095ed75df

commit r12-8994-g37595f8354e3e48e4a1a94537f3d1ae095ed75df
Author: Patrick Palka <ppalka@redhat.com>
Date:   Tue Nov 29 19:25:37 2022 -0500

    c++: ICE with <=> of incompatible pointers [PR107542]

    In a SFINAE context composite_pointer_type returns error_mark_node if
    the given pointer types are incompatible.  But the SPACESHIP_EXPR case
    of cp_build_binary_op wasn't prepared for this error_mark_node result,
    which led to an ICE (from spaceship_comp_cat) for the below testcase.
    (In a non-SFINAE context composite_pointer_type issues a permerror and
    returns cv void* in this case, so this ICE seems specific to SFINAE.)

            PR c++/107542

    gcc/cp/ChangeLog:

            * typeck.cc (cp_build_binary_op): In the SPACESHIP_EXPR case,
            handle an error_mark_node result type.

    gcc/testsuite/ChangeLog:

            * g++.dg/cpp2a/spaceship-sfinae2.C: New test.

    (cherry picked from commit 000e9863120cbc75a0f8d497264519974c97669f)

[Bug c++/107542] ICE in spaceship_comp_cat, at cp/method.cc:1055

[ppalka at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107542

Patrick Palka <ppalka at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|---                         |FIXED

--- Comment #8 from Patrick Palka <ppalka at gcc dot gnu.org> ---
Fixed for GCC 12.3/13, thanks for the bug report.