c++: ICE with variable template and [[deprecated]] [PR110031]

lookup_and_finish_template_variable already has and uses the complain
parameter but it is not passing it down to mark_used so we got the
default tf_warning_or_error, which causes various problems when
lookup_and_finish_template_variable gets called with complain=tf_none.

	PR c++/110031

gcc/cp/ChangeLog:

	* pt.cc (lookup_and_finish_template_variable): Pass complain to
	mark_used.

gcc/testsuite/ChangeLog:

	* g++.dg/cpp1z/inline-var11.C: New test.

2 files changed, 33 insertions, 1 deletions

diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc
index d73f6d9..040ced4 100644
--- a/gcc/cp/pt.cc
+++ b/gcc/cp/pt.cc
@@ -10533,7 +10533,7 @@ lookup_and_finish_template_variable (tree templ, tree targs,
   if (var == error_mark_node)
     return error_mark_node;
   var = finish_template_variable (var, complain);
-  mark_used (var);
+  mark_used (var, complain);
   return var;
 }
 
diff --git a/gcc/testsuite/g++.dg/cpp1z/inline-var11.C b/gcc/testsuite/g++.dg/cpp1z/inline-var11.C
new file mode 100644
index 0000000..d92911e
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp1z/inline-var11.C
@@ -0,0 +1,32 @@
+// PR c++/110031
+// { dg-do compile { target c++17 } }
+
+template <typename T>
+[[deprecated]]
+inline constexpr bool t = true ;
+
+template <bool a>
+struct enableif;
+
+template<>
+struct enableif<true>
+{
+        using y = int;
+};
+template <bool a>
+using enableif_t = typename enableif<a>::y;
+
+template <typename T, enableif_t<t<T>> = 0>   // { dg-warning "deprecated" }
+struct A {  A(T &&)  {  }};
+
+template <typename T>
+struct A<T> {
+  A(T &&) = delete;
+  A() = delete;
+};
+
+int main(void)
+{
+  A<double> a(5.3); // { dg-error "use of deleted function" }
+  return 0;
+}