obtained gcc-4.6.4.tar.bz2 from upstream website;upstream

verified gcc-4.6.4.tar.bz2.sig;
imported gcc-4.6.4 source tree from verified upstream tarball.

downloading a git-generated archive based on the 'upstream' tag
should provide you with a source tree that is binary identical
to the one extracted from the above tarball.

if you have obtained the source via the command 'git clone',
however, do note that line-endings of files in your working
directory might differ from line-endings of the respective
files in the upstream repository.

1 files changed, 86 insertions, 0 deletions

diff --git a/gcc/testsuite/g++.dg/abi/empty4.C b/gcc/testsuite/g++.dg/abi/empty4.C
new file mode 100644
index 000000000..d20a55cf7
--- /dev/null
+++ b/gcc/testsuite/g++.dg/abi/empty4.C
@@ -0,0 +1,86 @@
+// { dg-do run }
+
+// Copyright (C) 2001 Free Software Foundation, Inc.
+// Contributed by Nathan Sidwell 31 Jul 2001 <nathan@codesourcery.com>
+
+// Bug 3820. We were bit copying empty bases including the
+// padding. Which clobbers whatever they overlay.
+
+struct Empty {};
+
+struct Inter : Empty {};
+
+long now = 0;
+
+struct NonPod
+{
+  long m;
+
+  NonPod () {m = 0x12345678;}
+  NonPod (long m_) {m = m_;}
+  NonPod &operator= (NonPod const &src) {now = m; m = src.m; return *this;}
+  NonPod (NonPod const &src) {m = src.m;}
+};
+
+struct A : Inter
+{
+  A (long c) {m = c;}
+  
+  NonPod m;
+};
+
+struct B
+{
+  Inter empty;
+  NonPod m;
+
+  B (long c) {m = c;}
+};
+
+struct C : NonPod, Inter
+{
+  C (long c) : NonPod (c), Inter () {}
+};
+
+int main ()
+{
+  A a (0x12131415);
+  
+  long was = a.m.m;
+  
+  a = 0x22232425;
+
+  if (was != now)
+    return 1;	// we copied the empty base which clobbered a.m.m's
+		// original value.
+  
+  A b (0x32333435);
+  *(Inter *)&a = *(Inter *)&b;
+  
+  if (a.m.m != 0x22232425)
+    return 2;	// we copied padding, which clobbered a.m.m
+
+  A b2 (0x32333435);
+  (Inter &)b2 = Inter ();
+  if (b2.m.m != 0x32333435)
+    return 2;	// we copied padding, which clobbered b2.m.m
+  
+  B c (0x12131415);
+  was = c.m.m;
+  c = 0x22232425;
+  if (was != now)
+    return 3;
+  
+  B d (0x32333435);
+  c.empty = d.empty;
+
+  if (c.m.m != 0x22232425)
+    return 4;
+
+  C e (0x32333435);
+
+  if (e.m != 0x32333435)
+    return 2;	// we copied padding
+  
+  return 0;
+}