c++: partial ordering with memfn pointer cst [PR108104]
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Commit Message
Here we're triggering an overzealous assert in unify during partial
ordering since the member function pointer constants are represented as
ordinary CONSTRUCTORs (with TYPE_PTRMEMFUNC_P TREE_TYPE) but the assert
expects only COMPOUND_LITERAL_P constructors.
Bootstrapped and regtested on x86_64-pc-linux, does this look OK for
trunk and perhaps 12?
PR c++/108104
gcc/cp/ChangeLog:
* pt.cc (unify) <default>: Relax assert to accept any
CONSTRUCTOR not just COMPOUND_LITERAL_P ones.
gcc/testsuite/ChangeLog:
* g++.dg/template/ptrmem33.C: New test.
---
gcc/cp/pt.cc | 2 +-
gcc/testsuite/g++.dg/template/ptrmem33.C | 30 ++++++++++++++++++++++++
2 files changed, 31 insertions(+), 1 deletion(-)
create mode 100644 gcc/testsuite/g++.dg/template/ptrmem33.C
Comments
On 12/14/22 19:01, Patrick Palka wrote:
> Here we're triggering an overzealous assert in unify during partial
> ordering since the member function pointer constants are represented as
> ordinary CONSTRUCTORs (with TYPE_PTRMEMFUNC_P TREE_TYPE) but the assert
> expects only COMPOUND_LITERAL_P constructors.
>
> Bootstrapped and regtested on x86_64-pc-linux, does this look OK for
> trunk and perhaps 12?
OK for both.
> PR c++/108104
>
> gcc/cp/ChangeLog:
>
> * pt.cc (unify) <default>: Relax assert to accept any
> CONSTRUCTOR not just COMPOUND_LITERAL_P ones.
>
> gcc/testsuite/ChangeLog:
>
> * g++.dg/template/ptrmem33.C: New test.
> ---
> gcc/cp/pt.cc | 2 +-
> gcc/testsuite/g++.dg/template/ptrmem33.C | 30 ++++++++++++++++++++++++
> 2 files changed, 31 insertions(+), 1 deletion(-)
> create mode 100644 gcc/testsuite/g++.dg/template/ptrmem33.C
>
> diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc
> index 2f0f7a39698..44058d30799 100644
> --- a/gcc/cp/pt.cc
> +++ b/gcc/cp/pt.cc
> @@ -24921,7 +24921,7 @@ unify (tree tparms, tree targs, tree parm, tree arg, int strict,
> if (is_overloaded_fn (parm) || type_unknown_p (parm))
> return unify_success (explain_p);
> gcc_assert (EXPR_P (parm)
> - || COMPOUND_LITERAL_P (parm)
> + || TREE_CODE (parm) == CONSTRUCTOR
> || TREE_CODE (parm) == TRAIT_EXPR);
> expr:
> /* We must be looking at an expression. This can happen with
> diff --git a/gcc/testsuite/g++.dg/template/ptrmem33.C b/gcc/testsuite/g++.dg/template/ptrmem33.C
> new file mode 100644
> index 00000000000..dca741ae5e2
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/template/ptrmem33.C
> @@ -0,0 +1,30 @@
> +// PR c++/108104
> +// { dg-do compile { target c++11 } }
> +
> +struct A {
> + void x();
> + void y();
> +};
> +
> +enum State { On };
> +
> +template<State state, void (A::*)()>
> +struct B {
> + static void f();
> +};
> +
> +template<State state>
> +struct B<state, nullptr> {
> + static void g();
> +};
> +
> +template<State state>
> +struct B<state, &A::y> {
> + static void h();
> +};
> +
> +int main() {
> + B<State::On, &A::x>::f();
> + B<State::On, nullptr>::g();
> + B<State::On, &A::y>::h();
> +}
@@ -24921,7 +24921,7 @@ unify (tree tparms, tree targs, tree parm, tree arg, int strict,
if (is_overloaded_fn (parm) || type_unknown_p (parm))
return unify_success (explain_p);
gcc_assert (EXPR_P (parm)
- || COMPOUND_LITERAL_P (parm)
+ || TREE_CODE (parm) == CONSTRUCTOR
|| TREE_CODE (parm) == TRAIT_EXPR);
expr:
/* We must be looking at an expression. This can happen with
new file mode 100644
@@ -0,0 +1,30 @@
+// PR c++/108104
+// { dg-do compile { target c++11 } }
+
+struct A {
+ void x();
+ void y();
+};
+
+enum State { On };
+
+template<State state, void (A::*)()>
+struct B {
+ static void f();
+};
+
+template<State state>
+struct B<state, nullptr> {
+ static void g();
+};
+
+template<State state>
+struct B<state, &A::y> {
+ static void h();
+};
+
+int main() {
+ B<State::On, &A::x>::f();
+ B<State::On, nullptr>::g();
+ B<State::On, &A::y>::h();
+}