PR c++/88820 - ICE with CTAD and member template used in DMI.

Here the problem was that in order to form a FUNCTION_DECL for foo<int> in
the uninstantiated template, we were trying to deduce template args for S
from the template parm itself, and failing.

	* pt.c (do_class_deduction): Handle parm used as its own arg.

From-SVN: r269463

1 files changed, 9 insertions, 0 deletions

diff --git a/gcc/testsuite/g++.dg/cpp1z/class-deduction64.C b/gcc/testsuite/g++.dg/cpp1z/class-deduction64.C
new file mode 100644
index 0000000..3a06e6f
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp1z/class-deduction64.C
@@ -0,0 +1,9 @@
+// PR c++/88820
+// { dg-do compile { target c++17 } }
+
+template <int> struct S;
+
+template <S> struct W {
+  template <typename> static int foo();
+  bool b = foo<int>();
+};