Add mlpack::backtrace utility.

CMake/FindBfd.cmake

@@ -0,0 +1,89 @@
+# - Try to find libbfd
+# Once done this will define
+#
+#  LIBBFD_FOUND - system has libbfd
+#  LIBBFD_INCLUDE_DIRS - the libbfd include directory
+#  LIBBFD_LIBRARIES - Link these to use libbfd
+#  LIBBFD_DEFINITIONS - Compiler switches required for using libbfd
+#
+# Based on:
+#
+#  Copyright (c) 2008 Bernhard Walle <bernhard.walle@gmx.de>
+#
+#  Redistribution and use is allowed according to the terms of the New
+#  BSD license.
+#  For details see the accompanying COPYING-CMAKE-SCRIPTS file.
+#
+
+
+if (LIBBFD_LIBRARIES AND LIBBFD_INCLUDE_DIRS)
+  set (LIBBFD_FIND_QUIETLY TRUE)
+endif (LIBBFD_LIBRARIES AND LIBBFD_INCLUDE_DIRS)
+
+find_path (LIBBFD_INCLUDE_DIRS
+    NAMES
+      bfd.h
+      dis-asm.h
+    PATHS
+      /usr/include
+      /usr/local/include
+      /opt/local/include
+      /opt/include
+      ENV CPATH)
+
+# Ugly, yes ugly...
+find_library (LIBBFD_BFD_LIBRARY
+    NAMES
+      bfd
+    PATHS
+      /usr/lib
+      /usr/lib64
+      /usr/local/lib
+      /usr/local/lib64
+      /usr/include
+      /opt/local/lib
+      /opt/usr/lib64
+      ENV LIBRARY_PATH
+      ENV LD_LIBRARY_PATH)
+
+#find_library (LIBBFD_IBERTY_LIBRARY
+#    NAMES
+#      iberty
+#    PATHS
+#      /usr/lib
+#      /usr/lib64
+#      /usr/local/lib
+#      /usr/local/lib64
+#      /usr/include
+#      /opt/local/lib
+#      /opt/usr/lib64
+#      ENV LIBRARY_PATH
+#      ENV LD_LIBRARY_PATH)
+
+#find_library (LIBBFD_OPCODES_LIBRARY
+#    NAMES
+#      opcodes
+#    PATHS
+#      /usr/lib
+#      /usr/lib64
+#      /usr/local/lib
+#      /usr/local/lib64
+#      /usr/include
+#      /opt/local/lib
+#      /opt/usr/lib64
+#      ENV LIBRARY_PATH
+#      ENV LD_LIBRARY_PATH)
+
+
+include (FindPackageHandleStandardArgs)
+
+
+# handle the QUIETLY and REQUIRED arguments and set LIBBFD_FOUND to TRUE if all listed variables are TRUE
+FIND_PACKAGE_HANDLE_STANDARD_ARGS(LIBBFD DEFAULT_MSG
+    LIBBFD_BFD_LIBRARY
+#    LIBBFD_IBERTY_LIBRARY
+#    LIBBFD_OPCODES_LIBRARY
+    LIBBFD_INCLUDE_DIRS)
+
+set(LIBBFD_LIBRARIES "${LIBBFD_BFD_LIBRARY}")
+mark_as_advanced(LIBBFD_INCLUDE_DIRS LIBBFD_LIBRARIES)

CMake/FindLibDL.cmake

@@ -0,0 +1,32 @@
+# - Try to find libdl
+# Once done this will define
+#
+#  LIBDL_FOUND - system has libdl
+#  LIBDL_INCLUDE_DIRS - the libdl include directory
+#  LIBDL_LIBRARIES - Link these to use libdl
+#  LIBDL_NEEDS_UNDERSCORE - If extern "C" symbols are prefixed (BSD/Apple)
+#
+
+find_path (LIBDL_INCLUDE_DIRS NAMES dlfcn.h)
+find_library (LIBDL_LIBRARIES NAMES dl)
+include (FindPackageHandleStandardArgs)
+
+FIND_PACKAGE_HANDLE_STANDARD_ARGS(LibDL DEFAULT_MSG
+  LIBDL_LIBRARIES
+  LIBDL_INCLUDE_DIRS)
+
+SET(CMAKE_REQUIRED_LIBRARIES dl)
+INCLUDE(CheckCSourceRuns)
+CHECK_C_SOURCE_RUNS("#include <dlfcn.h>
+#include <stdlib.h>
+void testfunc() {}
+int main() {
+  testfunc();
+  if (dlsym(0, \"_testfunc\") != (void*)0) {
+    return EXIT_SUCCESS;
+  } else {
+    return EXIT_FAILURE;
+  }
+}" LIBDL_NEEDS_UNDERSCORE)
+
+mark_as_advanced(LIBDL_INCLUDE_DIRS LIBDL_LIBRARIES LIBDL_NEEDS_UNDERSCORE)

CMakeLists.txt

@@ -66,6 +66,20 @@ if(DEBUG)
   add_definitions(-DDEBUG)
   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -g -O0 -ftemplate-backtrace-limit=0")
   set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -std=c99 -g -O0")
+  # mlpack uses it's own mlpack::backtrace class based on Binary File Descriptor
+  # <bfd.h> and linux Dynamic Loader <libdl.h> and more portable version in future
+  if(CMAKE_SYSTEM_NAME STREQUAL "Linux")
+    find_package(Bfd)
+    find_package(LibDL)
+    if(LIBBFD_FOUND AND LIBDL_FOUND)
+      set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -rdynamic")
+      include_directories(${LIBBFD_INCLUDE_DIRS})
+      include_directories(${LIBDL_INCLUDE_DIRS})
+      add_definitions(-DHAS_BFD_DL)
+    else(LIBBFD_FOUND AND LIBDL_FOUND)
+      message(WARNING "No libBFD and/or libDL has been found!")
+    endif(LIBBFD_FOUND AND LIBDL_FOUND)
+  endif(CMAKE_SYSTEM_NAME STREQUAL "Linux")
 else()
   add_definitions(-DARMA_NO_DEBUG)
   add_definitions(-DNDEBUG)
@@ -80,16 +94,6 @@ if(CMAKE_COMPILER_IS_GNUCC AND PROFILE)
   set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -pg")
 endif(CMAKE_COMPILER_IS_GNUCC AND PROFILE)
 
-# mlpack uses backtrace() facilities. On some systems (e.g., GNU/Linux), it
-# resides in libc itself and requires <execinfo.h>; on other (e.g., OpenBSD)
-# it's provided by a separate library.
-find_package(Backtrace)
-if(Backtrace_FOUND)
-  include_directories(${Backtrace_INCLUDE_DIRS})
-  add_definitions(-DBACKTRACE_FOUND)
-  add_definitions(-DBACKTRACE_HEADER="${Backtrace_HEADER}")
-endif(Backtrace_FOUND)
-
 # If the user asked for running test cases with verbose output, turn that on.
 if(TEST_VERBOSE)
   add_definitions(-DTEST_VERBOSE)

doc/guide/iodoc.hpp

@@ -23,7 +23,8 @@ Output to Log::Debug does not show (and has no performance penalty) when mlpack
 is compiled without debugging symbols.  Output to Log::Info is only shown when
 the program is run with the --verbose (or -v) flag.  Log::Warn is always shown,
 and Log::Fatal will throw a std::runtime_error exception, when a newline is sent
-to it.
+to it only. If mlpack was compiled with debugging symbols, Log::Fatal will
+always throw a std::runtime_error exception and print backtrace.
 
 Here is a simple example, and its output:
 
@@ -48,13 +49,28 @@ int main(int argc, char** argv)
 }
 @endcode
 
-With debugging output and --verbose, the following is shown:
+With debugging output--verbose, the following is shown:
 
 @code
-$ ./main --verbose
 [DEBUG] Compiled with debugging symbols.
 [INFO ] Some test informational output.
 [WARN ] A warning!
+[FATAL] [bt]: (1) /absolute/path/to/file/example.cpp:6: function()
+[FATAL] Program has crashed.
+terminate called after throwing an instance of 'std::runtime_error'
+  what():  fatal error; see Log::Fatal output
+Aborted
+@endcode
+
+With debugging output, compilation flags -g -rdynamic and --verbose,
+the following is shown:
+
+@code
+[DEBUG] Compiled with debugging symbols.
+[INFO ] Some test informational output.
+[WARN ] A warning!
+[FATAL] Cannot give backtrace because program was compiled without: -g -rdynamic
+[FATAL] For a backtrace, recompile with: -g -rdynamic.
 [FATAL] Program has crashed.
 terminate called after throwing an instance of 'std::runtime_error'
   what():  fatal error; see Log::Fatal output

src/mlpack/CMakeLists.txt

@@ -41,11 +41,13 @@ if(UNIX AND NOT APPLE)
     target_link_libraries(mlpack rt)
 endif(UNIX AND NOT APPLE)
 
-# Log::Assert may require linking against whatever provides backtrace
-# functionality.
-if(Backtrace_FOUND)
-  target_link_libraries(mlpack ${Backtrace_LIBRARIES})
-endif(Backtrace_FOUND)
+# Backtrace for Linux need those libs.
+if(CMAKE_SYSTEM_NAME STREQUAL "Linux")
+  if(LIBBFD_FOUND AND LIBDL_FOUND AND DEBUG)
+    target_link_libraries(mlpack ${LIBBFD_LIBRARIES})
+    target_link_libraries(mlpack ${LIBDL_LIBRARIES})
+  endif(LIBBFD_FOUND AND LIBDL_FOUND AND DEBUG)
+endif(CMAKE_SYSTEM_NAME STREQUAL "Linux")
 
 # Collect all header files in the library.
 file(GLOB_RECURSE INCLUDE_H_FILES RELATIVE ${CMAKE_CURRENT_SOURCE_DIR} *.h)

src/mlpack/core.hpp

@@ -205,6 +205,10 @@
 #include <mlpack/core/dists/discrete_distribution.hpp>
 #include <mlpack/core/dists/gaussian_distribution.hpp>
 #include <mlpack/core/dists/laplace_distribution.hpp>
+//mlpack::backtrace only for linux
+#ifdef HAS_BFD_DL
+  #include <mlpack/core/util/backtrace.hpp>
+#endif
 
 // Include kernel traits.
 #include <mlpack/core/kernels/kernel_traits.hpp>

src/mlpack/core/util/CMakeLists.txt

@@ -3,6 +3,8 @@
 set(SOURCES
   arma_config.hpp
   arma_config_check.hpp
+  backtrace.hpp
+  backtrace.cpp
   cli.hpp
   cli.cpp
   cli_deleter.hpp