From: Richard Biener <rguenther@suse.de>
Date: Thu, 12 Jul 2018 07:13:36 +0000 (+0000)
Subject: re PR c/86453 (error: type variant differs by TYPE_PACKED in free_lang_data since... 
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=cd0762f3ca925ceaf69ae83442e08615fc1674e3;p=gcc.git

re PR c/86453 (error: type variant differs by TYPE_PACKED in free_lang_data since r255469)

2018-07-12  Richard Biener  <rguenther@suse.de>

	PR c/86453
	* c-attribs.c (handle_packed_attribute): Do not build a variant
	type with TYPE_PACKED, instead ignore the attribute if we may
	not apply to the original type.

	* g++.dg/warn/pr86453.C: New testcase.

From-SVN: r262575
---

diff --git a/gcc/c-family/ChangeLog b/gcc/c-family/ChangeLog
index a459f061326..115e032e41d 100644
--- a/gcc/c-family/ChangeLog
+++ b/gcc/c-family/ChangeLog
@@ -1,3 +1,10 @@
+2018-07-12  Richard Biener  <rguenther@suse.de>
+
+	PR c/86453
+	* c-attribs.c (handle_packed_attribute): Do not build a variant
+	type with TYPE_PACKED, instead ignore the attribute if we may
+	not apply to the original type.
+
 2018-07-10  Jakub Jelinek  <jakub@redhat.com>
 
 	PR c++/86443
diff --git a/gcc/c-family/c-attribs.c b/gcc/c-family/c-attribs.c
index f91add488bb..8cb87eb8154 100644
--- a/gcc/c-family/c-attribs.c
+++ b/gcc/c-family/c-attribs.c
@@ -502,8 +502,13 @@ handle_packed_attribute (tree *node, tree name, tree ARG_UNUSED (args),
   if (TYPE_P (*node))
     {
       if (!(flags & (int) ATTR_FLAG_TYPE_IN_PLACE))
-	*node = build_variant_type_copy (*node);
-      TYPE_PACKED (*node) = 1;
+	{
+	  warning (OPT_Wattributes,
+		   "%qE attribute ignored for type %qT", name, *node);
+	  *no_add_attrs = true;
+	}
+      else
+	TYPE_PACKED (*node) = 1;
     }
   else if (TREE_CODE (*node) == FIELD_DECL)
     {
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 0958a1a57b2..d68cccf3d0b 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2018-07-12  Richard Biener  <rguenther@suse.de>
+
+	PR c/86453
+	* g++.dg/warn/pr86453.C: New testcase.
+
 2018-07-12  Richard Biener  <rguenther@suse.de>
 
 	PR middle-end/86479
diff --git a/gcc/testsuite/g++.dg/warn/pr86453.C b/gcc/testsuite/g++.dg/warn/pr86453.C
new file mode 100644
index 00000000000..318f406b03d
--- /dev/null
+++ b/gcc/testsuite/g++.dg/warn/pr86453.C
@@ -0,0 +1,5 @@
+// { dg-do compile }
+// { dg-additional-options "-flto" { target lto } }
+struct X {
+  int *__attribute__((aligned(2), packed)) a; // { dg-warning "attribute ignored" }
+} b;