Merge branch 'next' of https://github.com/gnss-sdr/gnss-sdr into next

2024-12-15 12:40:35 +00:00 · 2019-03-10 13:55:58 +01:00 · 2019-03-10 13:55:58 +01:00 · 706ff23a7b
commit 706ff23a7b
parent 601443c04f b10aaafb86
21 changed files with 616 additions and 213 deletions
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
--- a/README.md
+++ b/README.md
@ -542,7 +542,7 @@ In a terminal, type:
 ~~~~~~
 $ sudo port selfupdate
 $ sudo port upgrade outdated
-$ sudo port install doxygen +latex
+$ sudo port install doxygen +docs
 $ sudo port install gnuradio
 $ sudo port install armadillo
 $ sudo port install gnutls
--- a/cmake/Modules/FindGNURADIO.cmake
+++ b/cmake/Modules/FindGNURADIO.cmake
@ -43,6 +43,9 @@ macro(LIST_CONTAINS var value)
  endforeach()
 endmacro()

+# Trick for feature_summary
+set(GNURADIO_FOUND TRUE)
+
 function(GR_MODULE EXTVAR PCNAME INCFILE LIBFILE)
    list_contains(REQUIRED_MODULE ${EXTVAR} ${GR_REQUIRED_COMPONENTS})
    if(NOT REQUIRED_MODULE)
@ -140,6 +143,7 @@ function(GR_MODULE EXTVAR PCNAME INCFILE LIBFILE)
    # generate an error if the module is missing
    if(NOT GNURADIO_${EXTVAR}_FOUND)
        message(STATUS "Required GNU Radio Component: ${EXTVAR} missing!")
+        set(GNURADIO_FOUND FALSE) # Trick for feature_summary
    endif()

    mark_as_advanced(GNURADIO_${EXTVAR}_LIBRARIES GNURADIO_${EXTVAR}_INCLUDE_DIRS)
@ -200,3 +204,6 @@ if(NOT PC_GNURADIO_RUNTIME_VERSION)
        set(PC_GNURADIO_RUNTIME_VERSION "3.8.0+")
    endif()
 endif()
+
+# Trick for feature_summary
+set(GNURADIO_FOUND TRUE)
--- a/cmake/Modules/FindGOOGLETEST.cmake
+++ b/cmake/Modules/FindGOOGLETEST.cmake
@ -0,0 +1,51 @@
+# Copyright (C) 2011-2019 (see AUTHORS file for a list of contributors)
+#
+# This file is part of GNSS-SDR.
+#
+# GNSS-SDR is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# GNSS-SDR 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 General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with GNSS-SDR. If not, see <https://www.gnu.org/licenses/>.
+
+
+# - Try to find Googletest source code
+#
+# The following environment variable is optionally searched for:
+# GTEST_DIR: Base directory where Googletest source code is found.
+#
+# The following are set after configuration is done:
+# GOOGLETEST_FOUND
+# LIBGTEST_DEV_DIR
+# GTEST_INCLUDE_DIRS
+
+
+find_path(LIBGTEST_DEV_DIR
+    NAMES src/gtest-all.cc
+    PATHS
+        ${GTEST_DIR}
+        ${GTEST_DIR}/googletest
+        /usr/src/googletest/googletest
+        /usr/src/gtest
+        /usr/include/gtest
+        /opt/local/src/gtest-1.7.0
+)
+
+find_path(GTEST_INCLUDE_DIRS
+    NAMES gtest/gtest.h
+    PATHS
+        ${GTEST_DIR}/googletest/include
+        /usr/include
+        /opt/local/src/gtest-1.7.0/include
+)
+
+include(FindPackageHandleStandardArgs)
+find_package_handle_standard_args(GOOGLETEST DEFAULT_MSG LIBGTEST_DEV_DIR GTEST_INCLUDE_DIRS)
+mark_as_advanced(LIBGTEST_DEV_DIR GTEST_INCLUDE_DIRS)
--- a/cmake/Modules/SetupPython.cmake
+++ b/cmake/Modules/SetupPython.cmake
@ -82,7 +82,6 @@ if(CMAKE_VERSION VERSION_LESS 3.12)
        gnsssdr_python_check_module("mako >= ${GNSSSDR_MAKO_MIN_VERSION}" mako "mako.__version__ >= '${GNSSSDR_MAKO_MIN_VERSION}'" MAKO_FOUND)
        gnsssdr_python_check_module("six - python 2 and 3 compatibility library" six "True" SIX_FOUND)
    endif()
-    find_package(PythonLibs ${PYTHON_VERSION_MAJOR}.${PYTHON_VERSION_MINOR} EXACT)
 else()
    find_package(Python3 COMPONENTS Interpreter)
    if(Python3_FOUND)
--- a/docs/changelog
+++ b/docs/changelog
@ -8,19 +8,22 @@
 ### Improvements in Efficiency

 - Improved preamble detection implementation in the decoding of navigation messages (acceleration by x1.6 on average).
- Applied clang-tidy checks and fixes related to performance.
+- Applied clang-tidy checks and fixes related to performance: performance-faster-string-find, performance-inefficient-algorithm, performance-move-const-arg, performance-type-promotion-in-math-fn, performance-unnecessary-copy-initialization, performance-unnecessary-value-param, readability-string-compare.


 ### Improvements in Interoperability:

 - Added the BeiDou B1I receiver chain.
 - Fix bug in GLONASS dual frequency receiver.
+- Added a custom UDP/IP output for PVT data streaming.
+- Improved Monitor block with UDP/IP output for internal receiver's data streaming.


 ### Improvements in Maintainability:

 - Usage of clang-tidy integrated into CMake scripts. New option -DENABLE_CLANG_TIDY=ON executes clang-tidy along with compilation. Requires clang compiler.
- Applied clang-tidy checks and fixes related to readability.
+- Applied clang-tidy checks and fixes related to readability: readability-container-size-empty, readability-identifier-naming, readability-inconsistent-declaration-parameter-name, readability-named-parameter, readability-non-const-parameter, readability-string-compare.
+- Improved includes selection following suggestions by include-what-you-use (see https://include-what-you-use.org/), allowing faster compiles, fewer recompiles and making refactoring easier.


 ### Improvements in Portability:
@ -31,13 +34,14 @@

 ### Improvements in Reliability

- Applied clang-tidy checks and fixes related to High Integrity C++.
+- Applied clang-tidy checks and fixes related to High Integrity C++: performance-move-const-arg, modernize-use-auto, modernize-use-equals-default, modernize-use-equals-delete, modernize-use-noexcept, modernize-use-nullptr, cert-dcl21-cpp, misc-new-delete-overloads, cert-dcl58-cpp, cert-err52-cpp, cert-err60-cpp.


 ### Improvements in Usability

 - The receiver now admits FPGA off-loading, allowing for real time operation at high sampling rates and higher number of signals and channels.
 - Fixed program termination (avoiding hangs and segfaults in some platforms/configurations).
+- CMake now generates a summary of enabled/disabled features. This info is also stored in a file called features.log in the building directory.
 - Improved information provided to the user in case of failure.


--- a/src/algorithms/libs/volk_gnsssdr_module/volk_gnsssdr/cmake/Modules/VolkPython.cmake
+++ b/src/algorithms/libs/volk_gnsssdr_module/volk_gnsssdr/cmake/Modules/VolkPython.cmake
@ -41,15 +41,23 @@ if(CMAKE_VERSION VERSION_LESS 3.12)
            find_package(PythonInterp ${VOLK_PYTHON3_MIN_VERSION} REQUIRED)
        endif()
    endif()
-    find_package(PythonLibs ${PYTHON_VERSION_MAJOR}.${PYTHON_VERSION_MINOR} EXACT)
 else()
    if(PYTHON_EXECUTABLE)
        message(STATUS "User set python executable ${PYTHON_EXECUTABLE}")
        find_package(PythonInterp ${VOLK_PYTHON_MIN_VERSION} REQUIRED)
    else()
-        find_package(Python COMPONENTS Interpreter)
-        set(PYTHON_VERSION_MAJOR ${Python_VERSION_MAJOR})
-        set(PYTHON_EXECUTABLE ${Python_EXECUTABLE})
+        find_package(Python3 COMPONENTS Interpreter)
+        if(Python3_FOUND)
+            set(PYTHON_EXECUTABLE ${Python3_EXECUTABLE})
+            set(PYTHON_VERSION_MAJOR ${Python3_VERSION_MAJOR})
+        endif()
+        if(NOT Python3_FOUND OR NOT MAKO_FOUND OR NOT SIX_FOUND)
+            find_package(Python2 COMPONENTS Interpreter)
+            if(Python2_FOUND)
+                set(PYTHON_EXECUTABLE ${Python2_EXECUTABLE})
+                set(PYTHON_VERSION_MAJOR ${Python2_VERSION_MAJOR})
+            endif()
+        endif()
    endif()
 endif()

--- a/src/algorithms/libs/volk_gnsssdr_module/volk_gnsssdr/lib/CMakeLists.txt
+++ b/src/algorithms/libs/volk_gnsssdr_module/volk_gnsssdr/lib/CMakeLists.txt
@ -313,6 +313,9 @@ if(NOT CROSSCOMPILE_MULTILIB AND CPU_IS_x86)
    #MSVC 64 bit does not have MMX, overrule it
    if(${SIZEOF_CPU} EQUAL 64 AND MSVC)
        overrule_arch(mmx "No MMX for Win64")
+        if(MSVC_VERSION GREATER 1700)
+            OVERRULE_ARCH(sse "No SSE for Win64 Visual Studio 2013")
+        endif()
    endif()

 endif()
@ -582,7 +585,7 @@ target_include_directories(volk_gnsssdr_obj

 #Add dynamic library
 add_library(volk_gnsssdr SHARED $<TARGET_OBJECTS:volk_gnsssdr_obj>)
-target_link_libraries(volk_gnsssdr ${volk_gnsssdr_libraries} m)
+target_link_libraries(volk_gnsssdr ${volk_gnsssdr_libraries})
 target_include_directories(volk_gnsssdr
    PUBLIC $<BUILD_INTERFACE:${PROJECT_BINARY_DIR}/include>
    PUBLIC $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include>
@ -593,7 +596,10 @@ target_include_directories(volk_gnsssdr
 )

 #Configure target properties
-set_target_properties(volk_gnsssdr_obj PROPERTIES COMPILE_FLAGS "-fPIC")
+if(NOT MSVC)
+    set_target_properties(volk_gnsssdr_obj PROPERTIES COMPILE_FLAGS "-fPIC")
+    target_link_libraries(volk_gnsssdr m)
+endif()
 set_target_properties(volk_gnsssdr PROPERTIES SOVERSION ${LIBVER})
 set_target_properties(volk_gnsssdr PROPERTIES DEFINE_SYMBOL "volk_gnsssdr_EXPORTS")

@ -608,7 +614,10 @@ install(TARGETS volk_gnsssdr
 #Configure static library
 if(ENABLE_STATIC_LIBS)
    add_library(volk_gnsssdr_static STATIC $<TARGET_OBJECTS:volk_gnsssdr_obj>)
-    target_link_libraries(volk_gnsssdr_static ${volk_gnsssdr_libraries} pthread m)
+    target_link_libraries(volk_gnsssdr_static ${volk_gnsssdr_libraries} pthread)
+    if(NOT MSVC)
+        target_link_libraries(volk_gnsssdr_static m)
+    endif()
    target_include_directories(volk_gnsssdr_static
        PUBLIC $<BUILD_INTERFACE:${PROJECT_BINARY_DIR}/include>
        PUBLIC $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include>
--- a/src/algorithms/signal_source/adapters/custom_udp_signal_source.h
+++ b/src/algorithms/signal_source/adapters/custom_udp_signal_source.h
@ -64,7 +64,7 @@ public:
    }

    /*!
-     * \brief Returns "UDP_Signal_Source"
+     * \brief Returns "Custom_UDP_Signal_Source"
     */
    inline std::string implementation() override
    {
--- a/src/algorithms/signal_source/adapters/gn3s_signal_source.h
+++ b/src/algorithms/signal_source/adapters/gn3s_signal_source.h
@ -59,11 +59,11 @@ public:
    }

    /*!
-     * \brief Returns "Gn3sSignalSource".
+     * \brief Returns "Gn3s_Signal_Source".
     */
    inline std::string implementation() override
    {
-        return "Gn3sSignalSource";
+        return "Gn3s_Signal_Source";
    }

    inline size_t item_size() override
--- a/src/core/libs/gnss_sdr_fpga_sample_counter.h
+++ b/src/core/libs/gnss_sdr_fpga_sample_counter.h
@ -48,6 +48,7 @@ gnss_sdr_fpga_sample_counter_sptr gnss_sdr_make_fpga_sample_counter(double _fs,
 class gnss_sdr_fpga_sample_counter : public gr::block
 {
 private:
+    friend gnss_sdr_fpga_sample_counter_sptr gnss_sdr_make_fpga_sample_counter(double _fs, int32_t _interval_ms);
    gnss_sdr_fpga_sample_counter(double _fs, int32_t _interval_ms);
    uint32_t test_register(uint32_t writeval);
    void configure_samples_per_output(uint32_t interval);
@ -76,7 +77,6 @@ private:
    bool is_open;

 public:
-    friend gnss_sdr_fpga_sample_counter_sptr gnss_sdr_make_fpga_sample_counter(double _fs, int32_t _interval_ms);
    ~gnss_sdr_fpga_sample_counter();
    int general_work(int noutput_items,
        gr_vector_int &ninput_items,
--- a/src/core/libs/gnss_sdr_sample_counter.cc
+++ b/src/core/libs/gnss_sdr_sample_counter.cc
@ -65,6 +65,9 @@ gnss_sdr_sample_counter::gnss_sdr_sample_counter(
 }


+gnss_sdr_sample_counter::~gnss_sdr_sample_counter() = default;
+
+
 gnss_sdr_sample_counter_sptr gnss_sdr_make_sample_counter(double _fs, int32_t _interval_ms, size_t _size)
 {
    gnss_sdr_sample_counter_sptr sample_counter_(new gnss_sdr_sample_counter(_fs, _interval_ms, _size));
--- a/src/core/libs/gnss_sdr_sample_counter.h
+++ b/src/core/libs/gnss_sdr_sample_counter.h
@ -51,6 +51,7 @@ gnss_sdr_sample_counter_sptr gnss_sdr_make_sample_counter(
 class gnss_sdr_sample_counter : public gr::sync_decimator
 {
 private:
+    friend gnss_sdr_sample_counter_sptr gnss_sdr_make_sample_counter(double _fs, int32_t _interval_ms, size_t _size);
    gnss_sdr_sample_counter(double _fs, int32_t _interval_ms, size_t _size);
    uint32_t samples_per_output;
    double fs;
@ -68,7 +69,7 @@ private:
    bool flag_enable_send_msg;

 public:
-    friend gnss_sdr_sample_counter_sptr gnss_sdr_make_sample_counter(double _fs, int32_t _interval_ms, size_t _size);
+    ~gnss_sdr_sample_counter();
    int work(int noutput_items,
        gr_vector_const_void_star &input_items,
        gr_vector_void_star &output_items);
--- a/src/core/libs/gnss_sdr_time_counter.cc
+++ b/src/core/libs/gnss_sdr_time_counter.cc
@ -52,6 +52,9 @@ gnss_sdr_time_counter::gnss_sdr_time_counter() : gr::block("time_counter",
 }


+gnss_sdr_time_counter::~gnss_sdr_time_counter() = default;
+
+
 gnss_sdr_time_counter_sptr gnss_sdr_make_time_counter()
 {
    gnss_sdr_time_counter_sptr counter_(new gnss_sdr_time_counter());
--- a/src/core/libs/gnss_sdr_time_counter.h
+++ b/src/core/libs/gnss_sdr_time_counter.h
@ -59,6 +59,7 @@ private:
    friend gnss_sdr_time_counter_sptr gnss_sdr_make_time_counter();

 public:
+    ~gnss_sdr_time_counter();
    int general_work(int noutput_items __attribute__((unused)), gr_vector_int &ninput_items __attribute__((unused)),
        gr_vector_const_void_star &input_items __attribute__((unused)), gr_vector_void_star &output_items);
 };
--- a/src/core/monitor/gnss_synchro_monitor.h
+++ b/src/core/monitor/gnss_synchro_monitor.h
@ -35,6 +35,8 @@
 #define GNSS_SDR_GNSS_SYNCHRO_MONITOR_H

 #include "gnss_synchro_udp_sink.h"
+#include <boost/shared_ptr.hpp>
+#include <gnuradio/runtime_types.h>  // for gr_vector_void_star
 #include <gnuradio/sync_block.h>
 #include <memory>
 #include <string>
@ -51,7 +53,9 @@ gnss_synchro_monitor_sptr gnss_synchro_make_monitor(unsigned int n_channels,
    const std::vector<std::string>& udp_addresses);

 /*!
- * \brief This class implements a block that computes the PVT solution with Galileo E1 signals
+ * \brief This class implements a monitoring block which allows sending
+ * a data stream with the receiver internal parameters (Gnss_Synchro objects)
+ * to local or remote clients over UDP.
 */
 class gnss_synchro_monitor : public gr::sync_block
 {
@ -61,21 +65,17 @@ private:
        int udp_port,
        const std::vector<std::string>& udp_addresses);

-    unsigned int d_nchannels;
-
-    int d_decimation_factor;
-
-    std::unique_ptr<Gnss_Synchro_Udp_Sink> udp_sink_ptr;
-
-    int count;
-
-
-public:
    gnss_synchro_monitor(unsigned int n_channels,
        int decimation_factor,
        int udp_port,
        const std::vector<std::string>& udp_addresses);

+    unsigned int d_nchannels;
+    int d_decimation_factor;
+    std::unique_ptr<Gnss_Synchro_Udp_Sink> udp_sink_ptr;
+    int count;
+
+public:
    ~gnss_synchro_monitor();  //!< Default destructor

    int work(int noutput_items, gr_vector_const_void_star& input_items,
--- a/src/core/monitor/gnss_synchro_udp_sink.cc
+++ b/src/core/monitor/gnss_synchro_udp_sink.cc
@ -44,6 +44,7 @@ Gnss_Synchro_Udp_Sink::Gnss_Synchro_Udp_Sink(std::vector<std::string> addresses,
        }
 }

+
 bool Gnss_Synchro_Udp_Sink::write_gnss_synchro(const std::vector<Gnss_Synchro>& stocks)
 {
    std::ostringstream archive_stream;
--- a/src/core/monitor/gnss_synchro_udp_sink.h
+++ b/src/core/monitor/gnss_synchro_udp_sink.h
@ -35,10 +35,15 @@
 #include "gnss_synchro.h"
 #include <boost/asio.hpp>
 #include <boost/system/error_code.hpp>
+#include <cstdint>
 #include <string>
 #include <vector>


+/*!
+ * \brief This class sends serialized Gnss_Synchro objects
+ * over UDP to one or multiple endpoints.
+ */
 class Gnss_Synchro_Udp_Sink
 {
 public:
--- a/src/core/receiver/gnss_flowgraph.cc
+++ b/src/core/receiver/gnss_flowgraph.cc
@ -1664,10 +1664,10 @@ void GNSSFlowgraph::init()

    if (enable_monitor_)
        {
-            GnssSynchroMonitor_ = gr::basic_block_sptr(new gnss_synchro_monitor(channels_count_,
+            GnssSynchroMonitor_ = gnss_synchro_make_monitor(channels_count_,
                configuration_->property("Monitor.decimation_factor", 1),
                configuration_->property("Monitor.udp_port", 1234),
-                udp_addr_vec));
+                udp_addr_vec);
        }
 }

--- a/src/core/system_parameters/GLONASS_L1_L2_CA.h
+++ b/src/core/system_parameters/GLONASS_L1_L2_CA.h
@ -52,7 +52,7 @@ const double GLONASS_F_M_A = 0.35e9;                           //!< Gravitationa
 const double GLONASS_SEMI_MAJOR_AXIS = 6378136;                //!< Semi-major axis of Earth [m]
 const double GLONASS_FLATTENING = 1 / 29825784;                //!< Flattening parameter
 const double GLONASS_GRAVITY = 97803284;                       //!< Equatorial acceleration of gravity [mGal]
-const double GLONASS_GRAVITY_CORRECTION = 0.87;                //!< Correction to acceleration of gravity at sea-level due to Atmosphere[мGal]
+const double GLONASS_GRAVITY_CORRECTION = 0.87;                //!< Correction to acceleration of gravity at sea-level due to Atmosphere[uGal]
 const double GLONASS_J2 = 1082625.75e-9;                       //!< Second zonal harmonic of the geopotential
 const double GLONASS_J4 = -2370.89e-9;                         //!< Fourth zonal harmonic of the geopotential
 const double GLONASS_J6 = 6.08e-9;                             //!< Sixth zonal harmonic of the geopotential
@ -74,7 +74,7 @@ const double GLONASS_MOON_SEMI_MAJOR_AXIS = 3.84385243e5;     //!< Semi-major ax
 const double GLONASS_MOON_ECCENTRICITY = 0.054900489;         //!< Eccentricity of lunar orbit
 const double GLONASS_MOON_INCLINATION = 0.000089803977407e3;  //!< Inclination of lunar orbit to ecliptic plane (5 deg 08 min 43.4 sec) [rad]

-const double GLONASS_SUN_OMEGA = 0.004908229466869e3;  //!< TODO What is this operation in the seconds with T?(281 deg 13 min 15.0 + 6189.03*Т sec) [rad]
+const double GLONASS_SUN_OMEGA = 0.004908229466869e3;  //!< TODO What is this operation in the seconds with T?(281 deg 13 min 15.0 + 6189.03 x T sec) [rad]
 const double GLONASS_SUN_Q0 = 0.006256583774423e3;     //!< (358 deg 28 min 33.04 sec) [rad]
 const double GLONASS_SUN_Q1 = 0e3;                     //!< TODO Why is the value greater than 60?(129596579.10 sec) [rad]
 const double GLONASS_SUN_GM = 0.1325263e12;            //!< Solar gravitational constant [km^3/s^2]
--- a/src/tests/CMakeLists.txt
+++ b/src/tests/CMakeLists.txt
@ -184,6 +184,12 @@ find_package(Gnuplot)
 if(GNUPLOT_FOUND)
    add_definitions(-DGNUPLOT_EXECUTABLE="${GNUPLOT_EXECUTABLE}")
 endif()
+set_package_properties(Gnuplot PROPERTIES
+    URL "http://www.gnuplot.info"
+    DESCRIPTION "A portable command-line driven graphing utility"
+    PURPOSE "Used to generate plots in some tests."
+    TYPE OPTIONAL
+)

 if(ENABLE_UNIT_TESTING_MINIMAL)
    add_definitions(-DUNIT_TESTING_MINIMAL=1)
@ -194,6 +200,15 @@ endif()
 # Optional generator
 ################################################################################
 option(ENABLE_GNSS_SIM_INSTALL "Enable the installation of gnss_sim on the fly" ON)
+add_feature_info(ENABLE_GNSS_SIM_INSTALL ENABLE_GNSS_SIM_INSTALL "Enables downloading and building of gnss-sim.")
+
+find_package(GPSTK)
+set_package_properties(GPSTK PROPERTIES
+    URL "http://www.gpstk.org"
+    DESCRIPTION "Library and suite of applications for satellite navigation"
+    PURPOSE "Used in some Extra Tests."
+    TYPE OPTIONAL
+)
 if(ENABLE_UNIT_TESTING_EXTRA OR ENABLE_SYSTEM_TESTING_EXTRA OR ENABLE_FPGA)
    if(ENABLE_FPGA)
      set(CROSS_INSTALL_DIR "-DCMAKE_INSTALL_PREFIX=${CMAKE_INSTALL_PREFIX}")
@ -239,7 +254,6 @@ if(ENABLE_UNIT_TESTING_EXTRA OR ENABLE_SYSTEM_TESTING_EXTRA OR ENABLE_FPGA)
    ################################################################################
    # Local installation of GPSTk http://www.gpstk.org/
    ################################################################################
-    find_package(GPSTK)
    if(NOT GPSTK_FOUND OR ENABLE_OWN_GPSTK)
      message(STATUS " GPSTk v${GNSSSDR_GPSTK_LOCAL_VERSION} will be automatically downloaded and built when doing 'make'.")
      if("${TOOLCHAIN_ARG}" STREQUAL "")