diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 174be40..7ca3a58 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -383,6 +383,7 @@ jobs:
             BUILD_JOBS=$((nproc || sysctl -n hw.ncpu) 2> /dev/null)
             echo "BUILD_JOBS=$BUILD_JOBS" >> $GITHUB_ENV
             echo "CMAKE_BUILD_PARALLEL_LEVEL=$BUILD_JOBS" >> $GITHUB_ENV
+            DEPINST_ARGS=()
             GIT_VERSION="$(git --version | sed -e 's/git version //')"
             GIT_HAS_JOBS=1
             if [ -f "/etc/debian_version" ]
@@ -409,25 +410,16 @@ jobs:
             fi
             if [ "$GIT_HAS_JOBS" -ne 0 ]
             then
-                GIT_ARGS="--jobs $GIT_FETCH_JOBS"
+                DEPINST_ARGS+=("--git_args" "--jobs $GIT_FETCH_JOBS")
             fi
             cd ..
             git clone -b "$BOOST_BRANCH" --depth 1 "https://github.com/boostorg/boost.git" "boost-root"
             cd boost-root
             mkdir -p libs/$LIBRARY
             cp -r $GITHUB_WORKSPACE/* libs/$LIBRARY
-            git submodule init tools/boost_install
-            git submodule init libs/headers
-            git submodule init tools/build
-            git submodule init tools/cmake
-            git submodule init libs/assert
-            git submodule init libs/config
-            git submodule init libs/static_assert
-            git submodule init libs/throw_exception
-            git submodule init libs/type_traits
-            git submodule init libs/utility
-            git submodule init libs/io
-            git submodule update $GIT_ARGS
+            git submodule update --init tools/boostdep
+            DEPINST_ARGS+=("$LIBRARY")
+            python tools/boostdep/depinst/depinst.py "${DEPINST_ARGS[@]}"
             ./bootstrap.sh
             ./b2 headers
             if [ -n "${{matrix.compiler}}" -o -n "$GCC_TOOLCHAIN_ROOT" ]
@@ -519,18 +511,8 @@ jobs:
             git clone -b %BOOST_BRANCH% --depth 1 https://github.com/boostorg/boost.git boost-root
             cd boost-root
             xcopy /s /e /q %GITHUB_WORKSPACE% libs\%LIBRARY%\
-            git submodule init tools/boost_install
-            git submodule init libs/headers
-            git submodule init tools/build
-            git submodule init tools/cmake
-            git submodule init libs/assert
-            git submodule init libs/config
-            git submodule init libs/static_assert
-            git submodule init libs/throw_exception
-            git submodule init libs/type_traits
-            git submodule init libs/utility
-            git submodule init libs/io
-            git submodule update --jobs %GIT_FETCH_JOBS%
+            git submodule update --init tools/boostdep
+            python tools/boostdep/depinst/depinst.py --git_args "--jobs %GIT_FETCH_JOBS%" %LIBRARY%
             cmd /c bootstrap
             b2 -d0 headers
 
@@ -569,21 +551,21 @@ jobs:
           REF=${GITHUB_BASE_REF:-$GITHUB_REF}
           REF=${REF#refs/heads/}
           echo REF: $REF
-          BOOST_BRANCH=develop && [ "$REF" == "master" ] && BOOST_BRANCH=master || true
+          BOOST_BRANCH=develop && [ "$REF" = "master" ] && BOOST_BRANCH=master || true
           echo BOOST_BRANCH: $BOOST_BRANCH
           cd ..
           git clone -b $BOOST_BRANCH --depth 1 https://github.com/boostorg/boost.git boost-root
           cd boost-root
           cp -r $GITHUB_WORKSPACE/* libs/$LIBRARY
           git submodule update --init tools/boostdep
-          python tools/boostdep/depinst/depinst.py --git_args "--jobs 3" $LIBRARY
+          python tools/boostdep/depinst/depinst.py --git_args "--jobs $GIT_FETCH_JOBS" $LIBRARY
 
       - name: Use library with add_subdirectory
         run: |
           cd ../boost-root/libs/$LIBRARY/test/cmake_subdir_test
           mkdir __build__ && cd __build__
           cmake ..
-          cmake --build .
+          cmake --build . -- -j $BUILD_JOBS
           ctest --output-on-failure --no-tests=error
 
   posix-cmake-install:
@@ -615,14 +597,14 @@ jobs:
           REF=${GITHUB_BASE_REF:-$GITHUB_REF}
           REF=${REF#refs/heads/}
           echo REF: $REF
-          BOOST_BRANCH=develop && [ "$REF" == "master" ] && BOOST_BRANCH=master || true
+          BOOST_BRANCH=develop && [ "$REF" = "master" ] && BOOST_BRANCH=master || true
           echo BOOST_BRANCH: $BOOST_BRANCH
           cd ..
           git clone -b $BOOST_BRANCH --depth 1 https://github.com/boostorg/boost.git boost-root
           cd boost-root
           cp -r $GITHUB_WORKSPACE/* libs/$LIBRARY
           git submodule update --init tools/boostdep
-          python tools/boostdep/depinst/depinst.py --git_args "--jobs 3" $LIBRARY
+          python tools/boostdep/depinst/depinst.py --git_args "--jobs $GIT_FETCH_JOBS" $LIBRARY
 
       - name: Configure
         run: |
@@ -633,13 +615,13 @@ jobs:
       - name: Install
         run: |
           cd ../boost-root/__build__
-          cmake --build . --target install
+          cmake --build . --target install -- -j $BUILD_JOBS
 
       - name: Use the installed library
         run: |
           cd ../boost-root/libs/$LIBRARY/test/cmake_install_test && mkdir __build__ && cd __build__
           cmake -DCMAKE_INSTALL_PREFIX=~/.local ..
-          cmake --build .
+          cmake --build . -- -j $BUILD_JOBS
           ctest --output-on-failure --no-tests=error
 
   posix-cmake-test:
@@ -671,14 +653,14 @@ jobs:
           REF=${GITHUB_BASE_REF:-$GITHUB_REF}
           REF=${REF#refs/heads/}
           echo REF: $REF
-          BOOST_BRANCH=develop && [ "$REF" == "master" ] && BOOST_BRANCH=master || true
+          BOOST_BRANCH=develop && [ "$REF" = "master" ] && BOOST_BRANCH=master || true
           echo BOOST_BRANCH: $BOOST_BRANCH
           cd ..
           git clone -b $BOOST_BRANCH --depth 1 https://github.com/boostorg/boost.git boost-root
           cd boost-root
           cp -r $GITHUB_WORKSPACE/* libs/$LIBRARY
           git submodule update --init tools/boostdep
-          python tools/boostdep/depinst/depinst.py --git_args "--jobs 3" $LIBRARY
+          python tools/boostdep/depinst/depinst.py --git_args "--jobs $GIT_FETCH_JOBS" $LIBRARY
 
       - name: Configure
         run: |
@@ -689,7 +671,7 @@ jobs:
       - name: Build tests
         run: |
           cd ../boost-root/__build__
-          cmake --build . --target tests
+          cmake --build . --target tests -- -j $BUILD_JOBS
 
       - name: Run tests
         run: |
diff --git a/appveyor.yml b/appveyor.yml
index b894436..ae3ed65 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -60,24 +60,15 @@ environment:
       CXXSTD: 03,11,14,1z
 
 install:
+  - set GIT_FETCH_JOBS=8
   - set BOOST_BRANCH=develop
   - if "%APPVEYOR_REPO_BRANCH%" == "master" set BOOST_BRANCH=master
   - cd ..
   - git clone -b %BOOST_BRANCH% https://github.com/boostorg/boost.git boost-root
   - cd boost-root
-  - git submodule init libs/headers
-  - git submodule init libs/assert
-  - git submodule init libs/config
-  - git submodule init libs/predef
-  - git submodule init libs/static_assert
-  - git submodule init libs/throw_exception
-  - git submodule init libs/type_traits
-  - git submodule init libs/utility
-  - git submodule init libs/io
-  - git submodule init tools/build
-  - git submodule init tools/boost_install
-  - git submodule update --jobs 4
+  - git submodule update --init tools/boostdep
   - xcopy /s /e /q %APPVEYOR_BUILD_FOLDER% libs\core\
+  - python tools/boostdep/depinst/depinst.py --git_args "--jobs %GIT_FETCH_JOBS%" core
   - cmd /c bootstrap
   - b2 headers
 
diff --git a/include/boost/core/fclose_deleter.hpp b/include/boost/core/fclose_deleter.hpp
index 7a0d34a..8f7a7fd 100644
--- a/include/boost/core/fclose_deleter.hpp
+++ b/include/boost/core/fclose_deleter.hpp
@@ -36,7 +36,8 @@ struct fclose_deleter
      */
     void operator() (std::FILE* p) const BOOST_NOEXCEPT
     {
-        std::fclose(p);
+        if (BOOST_LIKELY(!!p))
+            std::fclose(p);
     }
 };
 
diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index 7524ae6..5521551 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -27,6 +27,10 @@ set(BOOST_TEST_LINK_LIBRARIES Boost::core Boost::utility)
 
 boost_test(TYPE run SOURCES sv_conversion_test2.cpp)
 
+set(BOOST_TEST_LINK_LIBRARIES Boost::core Boost::config Boost::move Boost::smart_ptr)
+
+boost_test(TYPE run SOURCES fclose_deleter_test.cpp)
+
 endif()
 
 add_subdirectory(swap)
diff --git a/test/Jamfile.v2 b/test/Jamfile.v2
index 29003c1..63c3b9e 100644
--- a/test/Jamfile.v2
+++ b/test/Jamfile.v2
@@ -176,7 +176,7 @@ run demangle_test.cpp
 run demangled_name_test.cpp
   : : : <test-info>always_show_run_output ;
 
-run demangled_name_test.cpp  : : : <rtti>off <test-info>always_show_run_output : demangled_name_test_no_rtti ;
+run demangled_name_test.cpp : : : <rtti>off <test-info>always_show_run_output : demangled_name_test_no_rtti ;
 
 run scoped_enum.cpp ;
 compile-fail scoped_enum_compile_fail_conv_from_int.cpp
@@ -186,8 +186,7 @@ compile-fail scoped_enum_compile_fail_conv_to_int.cpp
 
 run underlying_type.cpp ;
 
-compile fclose_deleter_test.cpp
-  : <target-os>windows:<define>_CRT_SECURE_NO_WARNINGS <target-os>windows:<define>_CRT_SECURE_NO_DEPRECATE ;
+run fclose_deleter_test.cpp : : : <target-os>windows:<define>_CRT_SECURE_NO_WARNINGS <target-os>windows:<define>_CRT_SECURE_NO_DEPRECATE ;
 
 run pointer_traits_pointer_test.cpp ;
 run pointer_traits_element_type_test.cpp ;
diff --git a/test/fclose_deleter_test.cpp b/test/fclose_deleter_test.cpp
index dbe85a5..4363335 100644
--- a/test/fclose_deleter_test.cpp
+++ b/test/fclose_deleter_test.cpp
@@ -16,17 +16,29 @@
 #include <cstdio>
 #include <cstddef>
 #include <boost/config.hpp>
+#include <boost/move/unique_ptr.hpp>
+#include <boost/smart_ptr/shared_ptr.hpp>
 #if !defined(BOOST_NO_CXX11_SMART_PTR)
 #include <memory>
 #endif
 
+boost::movelib::unique_ptr< std::FILE, boost::fclose_deleter > make_boost_unique_file(const char* filename)
+{
+    return boost::movelib::unique_ptr< std::FILE, boost::fclose_deleter >(std::fopen(filename, "w"));
+}
+
+boost::shared_ptr< std::FILE > make_boost_shared_file(const char* filename)
+{
+    return boost::shared_ptr< std::FILE >(std::fopen(filename, "w"), boost::fclose_deleter());
+}
+
 #if !defined(BOOST_NO_CXX11_SMART_PTR)
-std::unique_ptr< std::FILE, boost::fclose_deleter > make_unique_file(const char* filename)
+std::unique_ptr< std::FILE, boost::fclose_deleter > make_std_unique_file(const char* filename)
 {
     return std::unique_ptr< std::FILE, boost::fclose_deleter >(std::fopen(filename, "w"));
 }
 
-std::shared_ptr< std::FILE > make_shared_file(const char* filename)
+std::shared_ptr< std::FILE > make_std_shared_file(const char* filename)
 {
     return std::shared_ptr< std::FILE >(std::fopen(filename, "w"), boost::fclose_deleter());
 }
@@ -43,9 +55,18 @@ int main()
         file = NULL;
     }
 
+    make_boost_unique_file(filename);
+    make_boost_shared_file(filename);
+
 #if !defined(BOOST_NO_CXX11_SMART_PTR)
-    make_unique_file(filename);
-    make_shared_file(filename);
+    make_std_unique_file(filename);
+    make_std_shared_file(filename);
+#endif
+
+    // Test if the deleter can be called on a NULL pointer
+    boost::shared_ptr< std::FILE >(static_cast< std::FILE* >(NULL), boost::fclose_deleter());
+#if !defined(BOOST_NO_CXX11_SMART_PTR)
+    std::shared_ptr< std::FILE >(static_cast< std::FILE* >(NULL), boost::fclose_deleter());
 #endif
 
     std::remove(filename);