Use libbacktrace to generate better leak callstacks.

git-svn-id: https://www.unprompted.com/svn/projects/tildefriends/trunk@3986 ed5197a5-7fde-0310-b194-c3ffbd925b24

deps/libbacktrace/edtest2.c

@@ -0,0 +1,43 @@
+/* edtest2.c -- Test for libbacktrace storage allocation stress handling (p2)
+   Copyright (C) 2017-2021 Free Software Foundation, Inc.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    (1) Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    (2) Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    (3) The name of the author may not be used to
+    endorse or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.  */
+
+/* This file intentionally written without any #include's
+ */
+
+extern int f3(int, int);
+extern int f2(int);
+
+int f2(int x)
+{
+  /* Returning a value here and elsewhere avoids a tailcall which
+     would mess up the backtrace.  */
+  return f3(x, __LINE__) + 3;
+}