c++: enum in generic lambda in template [PR95317]

Here we weren't instantiating the enumerators because the arglist still had
the template parameter for the generic lambda, so looking one up failed.  We
need to instantiate if the non-lambda enclosing scope is non-dependent.

gcc/cp/ChangeLog:

	PR c++/95317
	* pt.c (lookup_template_class_1): Do tsubst_enum when
	tsubsting a generic lambda.

gcc/testsuite/ChangeLog:

	PR c++/95317
	* g++.dg/cpp1y/lambda-generic-enum1.C: New test.

diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index d6a8ede..41bc633 100644 (file)
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -10173,7 +10173,8 @@ lookup_template_class_1 (tree d1, tree arglist, tree in_decl, tree context,
        = tree_cons (arglist, t,
                     DECL_TEMPLATE_INSTANTIATIONS (found));
 
-      if (TREE_CODE (template_type) == ENUMERAL_TYPE && !is_dependent_type
+      if (TREE_CODE (template_type) == ENUMERAL_TYPE
+         && !uses_template_parms (current_nonlambda_scope ())
          && !DECL_ALIAS_TEMPLATE_P (gen_tmpl))
        /* Now that the type has been registered on the instantiations
           list, we set up the enumerators.  Because the enumeration

diff --git a/gcc/testsuite/g++.dg/cpp1y/lambda-generic-enum1.C b/gcc/testsuite/g++.dg/cpp1y/lambda-generic-enum1.C
new file mode 100644 (file)
index 0000000..de15443
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp1y/lambda-generic-enum1.C
@@ -0,0 +1,10 @@
+// PR c++/95317
+// { dg-do compile { target c++14 } }
+
+template <typename> void fn1() {
+  [](auto) {
+    enum { VALUE };
+    VALUE;
+  };
+}
+int main() { fn1<void>; }