Support copying local_specializations.

	* cp-tree.h (enum lss_policy): New.
	(local_specialization_stack): Add policy parameter to default ctor.
	* pt.c (local_specialization_stack): Copy local_specializations if
	lss_copy.

From-SVN: r251424

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index f91f6be..b4e21f6 100644 (file)
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,5 +1,11 @@
 2017-08-29  Jason Merrill  <jason@redhat.com>
 
+       Support copying local_specializations.
+       * cp-tree.h (enum lss_policy): New.
+       (local_specialization_stack): Add policy parameter to default ctor.
+       * pt.c (local_specialization_stack): Copy local_specializations if
+       lss_copy.
+
        * constexpr.c (potential_constant_expression_1): Add "now" parm.
        (is_constant_expression, require_constant_expression): New.
        (is_static_init_expression, is_nondependent_constant_expression)

diff --git a/gcc/cp/cp-tree.h b/gcc/cp/cp-tree.h
index f0eafb3..a58e7bd 100644 (file)
--- a/gcc/cp/cp-tree.h
+++ b/gcc/cp/cp-tree.h
@@ -5117,9 +5117,10 @@ enum unification_kind_t {
 // An RAII class used to create a new pointer map for local
 // specializations. When the stack goes out of scope, the
 // previous pointer map is restored.
+enum lss_policy { lss_blank, lss_copy };
 struct local_specialization_stack
 {
-  local_specialization_stack ();
+  local_specialization_stack (lss_policy = lss_blank);
   ~local_specialization_stack ();
 
   hash_map<tree, tree> *saved;

diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index e34fe21..1b726ff 100644 (file)
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -77,10 +77,13 @@ static tree cur_stmt_expr;
 //
 // Implementation of the RAII helper for creating new local
 // specializations.
-local_specialization_stack::local_specialization_stack ()
+local_specialization_stack::local_specialization_stack (lss_policy policy)
   : saved (local_specializations)
 {
-  local_specializations = new hash_map<tree, tree>;
+  if (policy == lss_blank || !saved)
+    local_specializations = new hash_map<tree, tree>;
+  else
+    local_specializations = new hash_map<tree, tree>(*saved);
 }
 
 local_specialization_stack::~local_specialization_stack ()