Prepare for radical source tree reorganization. zack/build-layout-experiment

All top-level files and directories are moved into a temporary storage
directory, REORG.TODO, except for files that will certainly still
exist in their current form at top level when we're done (COPYING,
COPYING.LIB, LICENSES, NEWS, README), all old ChangeLog files (which
are moved to the new directory OldChangeLogs, instead), and the
generated file INSTALL (which is just deleted; in the new order, there
will be no generated files checked into version control).

1 files changed, 71 insertions, 0 deletions

diff --git a/REORG.TODO/dlfcn/bug-dl-leaf-lib.c b/REORG.TODO/dlfcn/bug-dl-leaf-lib.c
new file mode 100644
index 0000000000..9a1f3ce12a
--- /dev/null
+++ b/REORG.TODO/dlfcn/bug-dl-leaf-lib.c
@@ -0,0 +1,71 @@
+/* Make sure dlopen/dlclose are not marked as leaf functions.
+
+   Copyright (C) 2013-2017 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Mike Frysinger <vapier@gentoo.org>
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+/* The bug-dl-leaf.c file will call our lib_main directly.  We do this to
+   keep things simple -- no need to use --export-dynamic with the linker
+   or build the main ELF as a PIE.
+
+   The lib_main func will modify some of its state while dlopening and
+   dlclosing the bug-dl-leaf-lib-cb.so library.  The constructors and
+   destructors in that library will call back into this library to also
+   muck with state (the check_val_xxx funcs).
+
+   If dlclose/dlopen are marked as "leaf" functions, then with newer
+   versions of gcc, the state modification won't work correctly.  */
+
+#include <assert.h>
+#include <dlfcn.h>
+
+static int val = 1;
+static int called = 0;
+
+void check_val_init (void)
+{
+  called = 1;
+  assert (val == 2);
+}
+
+void check_val_fini (void)
+{
+  called = 2;
+  assert (val == 4);
+}
+
+int lib_main (void)
+{
+  int ret __attribute__ ((unused));
+  void *hdl;
+
+  /* Make sure the constructor sees the updated val.  */
+  val = 2;
+  hdl = dlopen ("bug-dl-leaf-lib-cb.so", RTLD_GLOBAL | RTLD_LAZY);
+  val = 3;
+  assert (hdl);
+  assert (called == 1);
+
+  /* Make sure the destructor sees the updated val.  */
+  val = 4;
+  ret = dlclose (hdl);
+  val = 5;
+  assert (ret == 0);
+  assert (called == 2);
+
+  return !val;
+}