C++ PATCH for c++/89297 - ICE with OVERLOAD in template

[Marek Polacek]

Here we ICE because we're in a template and the constructor contains an
OVERLOAD, so calling check_narrowing -> maybe_constant_value crashes.

check_narrowing deliberately calls maybe_constant_value and not
fold_non_dependent_expr so as to avoid instantiating expressions twice.

So let's use instantiate_non_dependent_expr_sfinae to deal with the OVERLOAD;
fold_non_dependent_expr always calls maybe_constant_value and we can avoid
that call.

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

2019-02-12  Marek Polacek  <pola...@redhat.com>

        PR c++/89297 - ICE with OVERLOAD in template.
        * semantics.c (finish_compound_literal): Call
        instantiate_non_dependent_expr_sfinae.

        * g++.dg/cpp0x/initlist113.C: New test.

diff --git gcc/cp/semantics.c gcc/cp/semantics.c
index 786f18ab0c8..e89a38d3cba 100644
--- gcc/cp/semantics.c
+++ gcc/cp/semantics.c
@@ -2826,9 +2826,13 @@ finish_compound_literal (tree type, tree 
compound_literal,
     return error_mark_node;
   compound_literal = reshape_init (type, compound_literal, complain);
   if (SCALAR_TYPE_P (type)
-      && !BRACE_ENCLOSED_INITIALIZER_P (compound_literal)
-      && !check_narrowing (type, compound_literal, complain))
-    return error_mark_node;
+      && !BRACE_ENCLOSED_INITIALIZER_P (compound_literal))
+    {
+      compound_literal
+       = instantiate_non_dependent_expr_sfinae (compound_literal, complain);
+      if (!check_narrowing (type, compound_literal, complain))
+       return error_mark_node;
+    }
   if (TREE_CODE (type) == ARRAY_TYPE
       && TYPE_DOMAIN (type) == NULL_TREE)
     {
diff --git gcc/testsuite/g++.dg/cpp0x/initlist113.C 
gcc/testsuite/g++.dg/cpp0x/initlist113.C
new file mode 100644
index 00000000000..0b7e7ff606a
--- /dev/null
+++ gcc/testsuite/g++.dg/cpp0x/initlist113.C
@@ -0,0 +1,11 @@
+// PR c++/89297
+// { dg-do compile { target c++11 } }
+
+int id(int v) { return v; }
+float id(float v) { return v; }
+
+template <typename>
+int foo(int v)
+{
+    return int{id(v)};
+}