Re: [PATCH] c++: noexcept and pointer to member function type [PR113108]

[Jason Merrill]

On 9/3/24 2:47 PM, Marek Polacek wrote:

Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk/14?

OK.

-- >8 --
We ICE in nothrow_spec_p because it got a DEFERRED_NOEXCEPT.
This DEFERRED_NOEXCEPT was created in implicitly_declare_fn
when declaring

   Foo& operator=(Foo&&) = default;

in the test.  The problem is that in resolve_overloaded_unification
we call maybe_instantiate_noexcept before try_one_overload only in
the TEMPLATE_ID_EXPR case.

        PR c++/113108

gcc/cp/ChangeLog:

        * pt.cc (resolve_overloaded_unification): Call
        maybe_instantiate_noexcept.

gcc/testsuite/ChangeLog:

        * g++.dg/cpp1z/noexcept-type28.C: New test.
---
  gcc/cp/pt.cc                                 |  2 ++
  gcc/testsuite/g++.dg/cpp1z/noexcept-type28.C | 18 ++++++++++++++++++
  2 files changed, 20 insertions(+)
  create mode 100644 gcc/testsuite/g++.dg/cpp1z/noexcept-type28.C

diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc
index 024fa8a5529..747e627f547 100644
--- a/gcc/cp/pt.cc
+++ b/gcc/cp/pt.cc
@@ -23787,6 +23787,8 @@ resolve_overloaded_unification (tree tparms,
      for (lkp_iterator iter (arg); iter; ++iter)
        {
        tree fn = *iter;
+       if (flag_noexcept_type)
+         maybe_instantiate_noexcept (fn, tf_none);
        if (try_one_overload (tparms, targs, tempargs, parm, TREE_TYPE (fn),
                              strict, sub_strict, addr_p, explain_p)
            && (!goodfn || !decls_match (goodfn, fn)))
diff --git a/gcc/testsuite/g++.dg/cpp1z/noexcept-type28.C 
b/gcc/testsuite/g++.dg/cpp1z/noexcept-type28.C
new file mode 100644
index 00000000000..bf0b927b8ec
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp1z/noexcept-type28.C
@@ -0,0 +1,18 @@
+// PR c++/113108
+// { dg-do compile { target c++17 } }
+
+template <typename T>
+struct Foo {
+    Foo& operator=(Foo&&) = default;
+    T data;
+};
+
+template <typename T>
+void consume(Foo<T>& (Foo<T>::*)(Foo<T>&&) ) {}
+
+template <typename T>
+void consume(Foo<T>& (Foo<T>::*)(Foo<T>&&) noexcept) {}
+
+int main() {
+    consume(&Foo<int>::operator=);
+}

base-commit: f0ab3de6ec0e3540f2e57f3f5628005f0a4e3fa5