From 3d8695f529a41a639c6cc2a51cbcec7c8b243bc1 Mon Sep 17 00:00:00 2001
From: Jason Merrill <jason@redhat.com>
Date: Fri, 12 Apr 2019 12:25:59 -0400
Subject: [PATCH] Avoid ICE on pmf{} in template.

Now that we return the original CONSTRUCTOR from finish_compound_literal,
the call to null_member_pointer_value_p in tsubst_copy_and_build was getting
confused because the CONSTRUCTOR was still empty rather than a valid PMF
value.

	* call.c (null_member_pointer_value_p): Handle an empty CONSTRUCTOR
	of PMF type.

From-SVN: r270324
---
 gcc/cp/ChangeLog                           |  5 +++++
 gcc/cp/call.c                              |  1 +
 gcc/testsuite/g++.dg/cpp0x/initlist-pmf1.C | 20 ++++++++++++++++++++
 3 files changed, 26 insertions(+)
 create mode 100644 gcc/testsuite/g++.dg/cpp0x/initlist-pmf1.C

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 8e63fdaac74..8b2e7574450 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,8 @@
+2019-04-12  Jason Merrill  <jason@redhat.com>
+
+	* call.c (null_member_pointer_value_p): Handle an empty CONSTRUCTOR
+	of PMF type.
+
 2019-04-12  Marek Polacek  <polacek@redhat.com>
 
 	* except.c (build_noexcept_spec): Use build_converted_constant_bool_expr
diff --git a/gcc/cp/call.c b/gcc/cp/call.c
index 519dad9bf2c..9582345d7e8 100644
--- a/gcc/cp/call.c
+++ b/gcc/cp/call.c
@@ -569,6 +569,7 @@ null_member_pointer_value_p (tree t)
     return false;
   else if (TYPE_PTRMEMFUNC_P (type))
     return (TREE_CODE (t) == CONSTRUCTOR
+	    && CONSTRUCTOR_NELTS (t)
 	    && integer_zerop (CONSTRUCTOR_ELT (t, 0)->value));
   else if (TYPE_PTRDATAMEM_P (type))
     return integer_all_onesp (t);
diff --git a/gcc/testsuite/g++.dg/cpp0x/initlist-pmf1.C b/gcc/testsuite/g++.dg/cpp0x/initlist-pmf1.C
new file mode 100644
index 00000000000..3035fefbc5f
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/initlist-pmf1.C
@@ -0,0 +1,20 @@
+// { dg-do compile { target c++11 } }
+
+struct A
+{
+  void f();
+};
+
+using ftype = decltype(&A::f);
+
+template <class T>
+bool f()
+{
+  ftype p = ftype{};
+  return p;
+}
+
+int main()
+{
+  f<int>();
+}
-- 
2.30.2