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+The libbacktrace library
+Initially written by Ian Lance Taylor <iant@google.com>
+
+The libbacktrace library may be linked into a program or library and
+used to produce symbolic backtraces.  Sample uses would be to print a
+detailed backtrace when an error occurs or to gather detailed
+profiling information.
+
+The libbacktrace library is provided under a BSD license.  See the
+source files for the exact license text.
+
+The public functions are declared and documented in the header file
+backtrace.h, which should be #include'd by a user of the library.
+
+Building libbacktrace will generate a file backtrace-supported.h,
+which a user of the library may use to determine whether backtraces
+will work.  See the source file backtrace-supported.h.in for the
+macros that it defines.
+
+As of September 2012, libbacktrace only supports ELF executables with
+DWARF debugging information.  The library is written to make it
+straightforward to add support for other object file and debugging
+formats.