With c++14 an NSDMI no longer makes a class type non-aggregate so it's
possible to perform aggregate initialization on a class that has an
NSDMI, but tsubst_copy() currently ICEs on a use of 'this' in such
a situation.
This patch makes tsubst_copy() handle a use of 'this' in an NSDMI as
part of an aggregate initialization. In that case current_class_ref
will be a PLACEHOLDER_EXPR (as set by get_nsdmi()) and this
PLACEHOLDER_EXPR will later get resolved to the true object by
replace_placeholders().
Does this patch look OK to commit after testing?
gcc/cp/ChangeLog:
PR c++/70332
* pt.c (tsubst_copy) [PARM_DECL]: Handle the use of 'this' in an
NSDMI that's part of an aggregrate initialization.
gcc/testsuite/ChangeLog:
PR c++/70332
* g++.dg/cpp1y/nsdmi-aggr5.C: New test.
---
gcc/cp/pt.c | 20 ++++++++++++++++----
gcc/testsuite/g++.dg/cpp1y/nsdmi-aggr5.C | 24 ++++++++++++++++++++++++
2 files changed, 40 insertions(+), 4 deletions(-)
create mode 100644 gcc/testsuite/g++.dg/cpp1y/nsdmi-aggr5.C
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index ebfc45b..49ef9d3 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -13878,10 +13878,22 @@ tsubst_copy (tree t, tree args, tsubst_flags_t
complain, tree in_decl)
if (r == NULL_TREE)
{
/* We get here for a use of 'this' in an NSDMI. */
- if (DECL_NAME (t) == this_identifier
- && current_function_decl
- && DECL_CONSTRUCTOR_P (current_function_decl))
- return current_class_ptr;
+ if (DECL_NAME (t) == this_identifier)
+ {
+ /* We're processing an NSDMI as part of a constructor call. */
+ if (current_function_decl
+ && DECL_CONSTRUCTOR_P (current_function_decl))
+ return current_class_ptr;
+
+ /* Or as part of an aggregate initialization. */
+ if (cp_unevaluated_operand == 0
+ && current_class_ref
+ && TREE_CODE (current_class_ref) == PLACEHOLDER_EXPR)
+ {
+ gcc_assert (cxx_dialect >= cxx14);
+ return current_class_ptr;
+ }
+ }
/* This can happen for a parameter name used later in a function
declaration (such as in a late-specified return type). Just
diff --git a/gcc/testsuite/g++.dg/cpp1y/nsdmi-aggr5.C
b/gcc/testsuite/g++.dg/cpp1y/nsdmi-aggr5.C
new file mode 100644
index 0000000..fe377c3
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp1y/nsdmi-aggr5.C
@@ -0,0 +1,24 @@
+// PR c++/70332
+// { dg-do run { target c++14 } }
+
+template <class T>
+struct C
+{
+ T m;
+ T *n = &m;
+};
+
+C<int> c { };
+
+int
+main ()
+{
+ *c.n = 5;
+ if (c.m != 5)
+ __builtin_abort ();
+
+ C<int> d { 10 };
+ *d.n = *d.n + 1;
+ if (d.m != 11)
+ __builtin_abort ();
+}
--
2.8.0.rc3.27.gade0865
