From: Patrick Palka <ppalka@gcc.gnu.org>
Date: Fri, 17 Apr 2015 12:14:24 +0000 (+0000)
Subject: re PR c++/64527 (Constructor for empty struct not called in some situations)
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=2234a9cb75c9f2ba6d6b944a93c673e5b3fc004a;p=gcc.git

re PR c++/64527 (Constructor for empty struct not called in some situations)

Fix PR c++/64527

gcc/
	PR c++/64527
	* gimplify.c (gimplify_init_constructor): Always emit a
	side-effecting constructor.

gcc/testsuite/
	PR c++/64527
	* g++.dg/init/pr64527.C: New test.

From-SVN: r222176
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 8929d06d5f9..bd25dd7f1f5 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2015-04-17  Patrick Palka  <ppalka@gcc.gnu.org>
+
+	PR c++/64527
+	* gimplify.c (gimplify_init_constructor): Always emit a
+	side-effecting constructor.
+
 2015-04-17  Tom de Vries  <tom@codesourcery.com>
 
 	PR tree-optimization/64950
diff --git a/gcc/gimplify.c b/gcc/gimplify.c
index 0394543ef7b..c701ef3954f 100644
--- a/gcc/gimplify.c
+++ b/gcc/gimplify.c
@@ -3994,6 +3994,9 @@ gimplify_init_constructor (tree *expr_p, gimple_seq *pre_p, gimple_seq *post_p,
 					pre_p, post_p, &preeval_data);
 	  }
 
+	bool ctor_has_side_effects_p
+	  = TREE_SIDE_EFFECTS (TREE_OPERAND (*expr_p, 1));
+
 	if (cleared)
 	  {
 	    /* Zap the CONSTRUCTOR element list, which simplifies this case.
@@ -4006,9 +4009,11 @@ gimplify_init_constructor (tree *expr_p, gimple_seq *pre_p, gimple_seq *post_p,
 	  }
 
 	/* If we have not block cleared the object, or if there are nonzero
-	   elements in the constructor, add assignments to the individual
-	   scalar fields of the object.  */
-	if (!cleared || num_nonzero_elements > 0)
+	   elements in the constructor, or if the constructor has side effects,
+	   add assignments to the individual scalar fields of the object.  */
+	if (!cleared
+	    || num_nonzero_elements > 0
+	    || ctor_has_side_effects_p)
 	  gimplify_init_ctor_eval (object, elts, pre_p, cleared);
 
 	*expr_p = NULL_TREE;
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 6b9b5766c6b..1f9f1d4e03c 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2015-04-17  Patrick Palka  <ppalka@gcc.gnu.org>
+
+	PR c++/64527
+	* g++.dg/init/pr64527.C: New test.
+
 2015-04-17  Tom de Vries  <tom@codesourcery.com>
 	    Michael Matz  <matz@suse.de>
 
diff --git a/gcc/testsuite/g++.dg/init/pr64527.C b/gcc/testsuite/g++.dg/init/pr64527.C
new file mode 100644
index 00000000000..36b82141cae
--- /dev/null
+++ b/gcc/testsuite/g++.dg/init/pr64527.C
@@ -0,0 +1,21 @@
+// { dg-do run { target c++11 } }
+
+static int g;
+
+struct A {
+  A() { g = 1; }
+};
+
+struct accessor {
+  A a;
+  int x;
+};
+
+int
+main (void)
+{
+  (void) accessor{};
+
+  if (g != 1)
+    __builtin_abort ();
+}