From 0d8ab59ce04e7df40bf505c7e341599b141e98c4 Mon Sep 17 00:00:00 2001
From: Jason Merrill <jason@redhat.com>
Date: Tue, 20 Oct 2015 02:49:13 -0400
Subject: [PATCH] re PR c++/67064 (Register asm variable broken)

	PR c++/67064

	* semantics.c (force_paren_expr): Don't mess with hard register vars.

From-SVN: r229021
---
 gcc/cp/ChangeLog                     |  3 +++
 gcc/cp/semantics.c                   |  2 ++
 gcc/testsuite/g++.dg/parse/parens3.C | 18 ++++++++++++++++++
 3 files changed, 23 insertions(+)
 create mode 100644 gcc/testsuite/g++.dg/parse/parens3.C

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 842426b5f2d..6ffa733c0ac 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,5 +1,8 @@
 2015-10-19  Jason Merrill  <jason@redhat.com>
 
+	PR c++/67064
+	* semantics.c (force_paren_expr): Don't mess with hard register vars.
+
 	Implement N4268, Do constant evaluation of all non-type template args.
 	* parser.c (cp_parser_template_argument): For C++1z just parse a
 	constant-expression.
diff --git a/gcc/cp/semantics.c b/gcc/cp/semantics.c
index 8796b176c15..c0a8b322767 100644
--- a/gcc/cp/semantics.c
+++ b/gcc/cp/semantics.c
@@ -1660,6 +1660,8 @@ force_paren_expr (tree expr)
     REF_PARENTHESIZED_P (expr) = true;
   else if (type_dependent_expression_p (expr))
     expr = build1 (PAREN_EXPR, TREE_TYPE (expr), expr);
+  else if (VAR_P (expr) && DECL_HARD_REGISTER (expr))
+    /* We can't bind a hard register variable to a reference.  */;
   else
     {
       cp_lvalue_kind kind = lvalue_kind (expr);
diff --git a/gcc/testsuite/g++.dg/parse/parens3.C b/gcc/testsuite/g++.dg/parse/parens3.C
new file mode 100644
index 00000000000..afb392bc5da
--- /dev/null
+++ b/gcc/testsuite/g++.dg/parse/parens3.C
@@ -0,0 +1,18 @@
+// PR c++/67064
+// { dg-options "-w" }
+
+struct s {
+  int i;
+};
+
+register struct s *reg __asm__( "1" );
+
+int f(void)
+{
+  int i;
+
+  i = reg->i;
+  i = (reg)->i;
+
+  return i;
+}
-- 
2.30.2