[gcc/devel/ranger] Add testcase of PR c++/90448, already fixed in trunk.

[Aldy Hernandez]

https://gcc.gnu.org/g:183e9006cc0300257d6f74d573514ef86f78cb4e

commit 183e9006cc0300257d6f74d573514ef86f78cb4e
Author: Paolo Carlini <paolo.carlini@oracle.com>
Date:   Wed Apr 22 18:05:18 2020 +0200

    Add testcase of PR c++/90448, already fixed in trunk.
    
            PR c++/90448
            * g++.dg/cpp1y/lambda-generic-variadic20.C: New.

Diff:
---
 gcc/testsuite/ChangeLog                                |  5 +++++
 gcc/testsuite/g++.dg/cpp1y/lambda-generic-variadic20.C | 16 ++++++++++++++++
 2 files changed, 21 insertions(+)

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index e60da71c99c..f6dd7ac6777 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2020-04-22  Paolo Carlini  <paolo.carlini@oracle.com>
+
+	PR c++/90448
+	* g++.dg/cpp1y/lambda-generic-variadic20.C: New.
+
 2020-04-22  Martin Sebor  <msebor@redhat.com>
 
 	PR middle-end/94647
diff --git a/gcc/testsuite/g++.dg/cpp1y/lambda-generic-variadic20.C b/gcc/testsuite/g++.dg/cpp1y/lambda-generic-variadic20.C
new file mode 100644
index 00000000000..3af971bbf12
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp1y/lambda-generic-variadic20.C
@@ -0,0 +1,16 @@
+// PR c++/90448
+// { dg-do compile { target c++14 } }
+
+template<class ... Ts> int fooV(Ts ... ts) {
+  auto L = [](auto ... a) {
+    auto M = [](decltype(a) ... b) -> void {
+    };
+    return M;
+  };
+
+  decltype(L(L, ts...)) (*fp)(decltype(L), decltype(ts) ...) = L;
+
+  return 0;
+}
+
+int run2 = fooV("BC", 3, 2.77, 'A', float{}, short{}, unsigned{});