From: Marek Polacek <polacek@redhat.com>
Date: Wed, 12 Jun 2019 21:12:00 +0000 (+0000)
Subject: PR c++/90736 - bogus error with alignof.
X-Git-Tag: releases/gcc-9.2.0~252
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=cac965a90839a00be784adb67471a7aaadab3ff9;p=thirdparty%2Fgcc.git

PR c++/90736 - bogus error with alignof.

	* constexpr.c (adjust_temp_type): Use cv_unqualified type.

	* g++.dg/cpp0x/alignof5.C: New test.

From-SVN: r272219
---

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 8e33634f7a01..af8a3ccbe1d3 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,8 @@
+2019-06-12  Marek Polacek  <polacek@redhat.com>
+
+	PR c++/90736 - bogus error with alignof.
+	* constexpr.c (adjust_temp_type): Use cv_unqualified type.
+
 2019-06-11  Jakub Jelinek  <jakub@redhat.com>
 
 	PR c++/90810
diff --git a/gcc/cp/constexpr.c b/gcc/cp/constexpr.c
index 9c13f0d5f320..96558b839ab2 100644
--- a/gcc/cp/constexpr.c
+++ b/gcc/cp/constexpr.c
@@ -1337,7 +1337,9 @@ adjust_temp_type (tree type, tree temp)
   if (TREE_CODE (temp) == EMPTY_CLASS_EXPR)
     return build0 (EMPTY_CLASS_EXPR, type);
   gcc_assert (scalarish_type_p (type));
-  return cp_fold_convert (type, temp);
+  /* Now we know we're dealing with a scalar, and a prvalue of non-class
+     type is cv-unqualified.  */
+  return cp_fold_convert (cv_unqualified (type), temp);
 }
 
 /* Callback for walk_tree used by unshare_constructor.  */
diff --git a/gcc/testsuite/g++.dg/cpp0x/alignof5.C b/gcc/testsuite/g++.dg/cpp0x/alignof5.C
new file mode 100644
index 000000000000..09354d3e1d01
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/alignof5.C
@@ -0,0 +1,6 @@
+// PR c++/90736 - bogus error with alignof.
+// { dg-do compile { target c++11 } }
+
+constexpr int fn(const int b) { return b; }
+constexpr int c = fn(alignof(int));
+alignas(c) char d;