From 4ffbff5906ce6291c39852f0856b5f6a60a3d3e1 Mon Sep 17 00:00:00 2001
From: Jason Merrill <jason@gcc.gnu.org>
Date: Fri, 18 Jan 2002 08:23:23 -0500
Subject: [PATCH] C++ ABI change: destroy value arguments in caller.
* calls.c (initialize_argument_information): Pass the address of
the TARGET_EXPR temporary rather than storing it into another.
From-SVN: r48983
---
gcc/testsuite/g++.dg/init/elide1.C | 38 ++++++++++++++++++++++++++++++
1 file changed, 38 insertions(+)
create mode 100644 gcc/testsuite/g++.dg/init/elide1.C
diff --git a/gcc/testsuite/g++.dg/init/elide1.C b/gcc/testsuite/g++.dg/init/elide1.C
new file mode 100644
index 000000000000..24e81e387e55
--- /dev/null
+++ b/gcc/testsuite/g++.dg/init/elide1.C
@@ -0,0 +1,38 @@
+// { dg-do run }
+
+// Test that the destructor for a temporary passed by value isn't run
+// until end of full-expression, as per [class.copy]:
+
+// Whenever a temporary class object is copied using a copy constructor,
+// and this object and the copy have the same cv-unqualified type, an
+// implementation is permitted to treat the original and the copy as two
+// different ways of referring to the same object and not perform a copy
+// at all, even if the class copy constructor or destructor have side
+// effects.... In these cases, the
+// object is destroyed at the later of times when the original and the
+// copy would have been destroyed without the optimization.
+
+// Here, the temporary would be destroyed later than the parm, so either we
+// must suppress the optimization in this case or destroy value parms in the
+// caller.
+
+int d;
+
+struct A {
+ A () { }
+ A (const A&) { }
+ ~A() { ++d; }
+};
+
+void f (A a) { }
+
+int main ()
+{
+ int r;
+ f (A ()), r = d;
+
+ if (r < d && d)
+ return 0;
+ else
+ return 1;
+}
--
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