CXX-2814 Remove BSONCXX_POLY_USE_STD_EXPERIMENTAL from polyfill options (#1089)

Author: eramongodb

.evergreen/compile.sh

@@ -23,7 +23,6 @@ set -o pipefail
 : "${REQUIRED_CXX_STANDARD:-}"
 : "${RUN_DISTCHECK:-}"
 : "${USE_POLYFILL_BOOST:-}"
-: "${USE_POLYFILL_STD_EXPERIMENTAL:-}"
 : "${USE_SANITIZER_ASAN:-}"
 : "${USE_SANITIZER_UBSAN:-}"
 : "${USE_STATIC_LIBS:-}"
@@ -136,13 +135,6 @@ esac
 export CMAKE_GENERATOR="${generator:?}"
 export CMAKE_GENERATOR_PLATFORM="${platform:-}"
 
-if [[ "${USE_POLYFILL_STD_EXPERIMENTAL:-}" == "ON" ]]; then
-  cmake_flags+=(
-    "-DCMAKE_CXX_STANDARD=14"
-    "-DBSONCXX_POLY_USE_STD_EXPERIMENTAL=ON"
-  )
-fi
-
 if [[ "${USE_POLYFILL_BOOST:-}" == "ON" ]]; then
   cmake_flags+=("-DBSONCXX_POLY_USE_BOOST=ON")
 fi

.mci.yml

@@ -469,7 +469,6 @@ functions:
                   - REQUIRED_CXX_STANDARD
                   - RUN_DISTCHECK
                   - USE_POLYFILL_BOOST
-                  - USE_POLYFILL_STD_EXPERIMENTAL
                   - USE_SANITIZER_ASAN
                   - USE_SANITIZER_UBSAN
                   - USE_STATIC_LIBS
@@ -1685,24 +1684,6 @@ buildvariants:
           - name: build_example_with_add_subdirectory
           - name: uninstall_check
 
-    # TODO CXX-2260 Upgrade std::experimental tasks to use Ubuntu 18.04 and mongodb_latest
-    # after bug fixes with newer g++ versions.
-    - name: ubuntu1604-debug-std-experimental
-      display_name: "Ubuntu 16.04 Debug (std::experimental) (MongoDB 4.4)"
-      expansions:
-          build_type: "Debug"
-          USE_POLYFILL_STD_EXPERIMENTAL: ON
-          mongodb_version: "4.4"
-          example_projects_cxx_standard: 14
-          use_mongocryptd: true  # crypt_shared is not available for Ubuntu 16.04
-      run_on:
-          - ubuntu1604-build
-      tasks:
-          - name: compile_and_test_with_shared_libs
-          - name: compile_and_test_with_shared_libs_extra_alignment
-          - name: compile_and_test_with_static_libs
-          - name: compile_and_test_with_static_libs_extra_alignment
-
     - name: ubuntu2004-debug-valgrind-latest
       display_name: "Valgrind Ubuntu 20.04 Debug (MongoDB Latest)"
       expansions:

CHANGELOG.md

@@ -33,6 +33,7 @@ Changes prior to 3.9.0 are documented as [release notes on GitHub](https://githu
     Use `find_package(bsoncxx)` and `find_package(mongocxx)` instead.
   - Accordingly, `LIBBSONCXX_*` and `LIBMONGOCXX_*` CMake variables provided by the legacy CMake package config files are no longer supported. Use the `mongo::bsoncxx_*` and `mongo::mongocxx_*` CMake targets instead.
   - Note: manually setting compile definitions, include directories, and link libraries is unnecessary with target-based CMake. The former `LIBBSONCXX_*` and `LIBMONGOCXX_*` CMake variables are superseded by the `target_link_libraries()` CMake command, which automatically propagates the necessary compile definitions, include directories, and link libraries to dependent targets via `mongo::bsoncxx_*` and `mongo::mongocxx_*` interface properties.
+- Experimental C++ standard library as a polyfill option via `BSONCXX_POLY_USE_STD_EXPERIMENTAL`.
 
 ## 3.9.0
 

CMakeLists.txt

@@ -460,10 +460,6 @@ if(NOT(TARGET dist OR TARGET distcheck))
         list(APPEND polyfill_flags "-DBSONCXX_POLY_USE_MNMLSTC=${BSONCXX_POLY_USE_MNMLSTC}")
     endif()
 
-    if(NOT "${BSONCXX_POLY_USE_STD_EXPERIMENTAL}" STREQUAL "")
-        list(APPEND polyfill_flags "-DBSONCXX_POLY_USE_STD_EXPERIMENTAL=${BSONCXX_POLY_USE_STD_EXPERIMENTAL}")
-    endif()
-
     if(NOT "${BSONCXX_POLY_USE_SYSTEM_MNMLSTC}" STREQUAL "")
         list(APPEND polyfill_flags "-DBSONCXX_POLY_USE_SYSTEM_MNMLSTC=${BSONCXX_POLY_USE_SYSTEM_MNMLSTC}")
     endif()

cmake/BsoncxxUtil.cmake

@@ -55,22 +55,19 @@ function(bsoncxx_add_library TARGET OUTPUT_NAME LINK_TYPE)
         # Library used for C++17 polyfills:
         # - 'm' for mnmlstc/core.
         # - 'b' for Boost.
-        # - 'x' for experimental standard library.
         # - 'i' for bsoncxx implementations.
         # - 's' for standard library (no polyfill).
         if(1)
             if(BSONCXX_POLY_USE_MNMLSTC)
                 set(polyfill "m")
             elseif(BSONCXX_POLY_USE_BOOST)
                 set(polyfill "b")
-            elseif(BSONCXX_POLY_USE_STD_EXPERIMENTAL)
-                set(polyfill "x")
             elseif(0) # CXX-2796: reserved for bsoncxx implementations as polyfill.
                 set(polyfill "i")
             elseif(BSONCXX_POLY_USE_STD)
                 set(polyfill "s")
             else()
-                message(FATAL_ERROR "could not determine polyfill library: must be one of [mbxis]")
+                message(FATAL_ERROR "could not determine polyfill library: must be one of [mbis]")
             endif()
 
             set_target_properties(${TARGET} PROPERTIES INTERFACE_BSONCXX_ABI_TAG_POLYFILL_LIBRARY ${polyfill})

cmake/make_dist/MakeDistCheck.cmake

@@ -39,9 +39,6 @@ function (RUN_DIST_CHECK PACKAGE_PREFIX EXT)
    if (NOT "${BSONCXX_POLY_USE_MNMLSTC}" STREQUAL "")
       list(APPEND polyfill_flags "-DBSONCXX_POLY_USE_MNMLSTC=${BSONCXX_POLY_USE_MNMLSTC}")
    endif()
-   if (NOT "${BSONCXX_POLY_USE_STD_EXPERIMENTAL}" STREQUAL "")
-      list(APPEND polyfill_flags "-DBSONCXX_POLY_USE_STD_EXPERIMENTAL=${BSONCXX_POLY_USE_STD_EXPERIMENTAL}")
-   endif()
    if (NOT "${BSONCXX_POLY_USE_SYSTEM_MNMLSTC}" STREQUAL "")
       list(APPEND polyfill_flags "-DBSONCXX_POLY_USE_SYSTEM_MNMLSTC=${BSONCXX_POLY_USE_SYSTEM_MNMLSTC}")
    endif()

docs/content/mongocxx-v3/installation/linux.md

@@ -26,15 +26,6 @@ must choose one of the following implementations for these features:
      only option if you are using a version of MSVC that does not support
      C++17.
 
-   `std::experimental`
-     Select with `-DBSONCXX_POLY_USE_STD_EXPERIMENTAL=1`. If your
-     toolchain's standard library provides `optional` and
-     `string_view` in the namespace `std::experimental`, you can use
-     this option. Be aware that your standard library's
-     `std::experimental` implementation may change over time,
-     breaking binary compatibility in unexpected ways. Note that this
-     polyfill is *not* recommended and is unsupported.
-
 Most users should be fine sticking with the default. However, if you
 have an existing application which makes heavy use of one of the
 available libraries, you may prefer to build the mongocxx driver

docs/content/mongocxx-v3/installation/macos.md

@@ -26,15 +26,6 @@ must choose one of the following implementations for these features:
      only option if you are using a version of MSVC that does not support
      C++17.
 
-   `std::experimental`
-     Select with `-DBSONCXX_POLY_USE_STD_EXPERIMENTAL=1`. If your
-     toolchain's standard library provides `optional` and
-     `string_view` in the namespace `std::experimental`, you can use
-     this option. Be aware that your standard library's
-     `std::experimental` implementation may change over time,
-     breaking binary compatibility in unexpected ways. Note that this
-     polyfill is *not* recommended and is unsupported.
-
 Most users should be fine sticking with the default. However, if you
 have an existing application which makes heavy use of one of the
 available libraries, you may prefer to build the mongocxx driver

docs/content/mongocxx-v3/installation/windows.md

@@ -26,15 +26,6 @@ must choose one of the following implementations for these features:
      only option if you are using a version of MSVC that does not support
      C++17.
 
-   `std::experimental`
-     Select with `-DBSONCXX_POLY_USE_STD_EXPERIMENTAL=1`. If your
-     toolchain's standard library provides `optional` and
-     `string_view` in the namespace `std::experimental`, you can use
-     this option. Be aware that your standard library's
-     `std::experimental` implementation may change over time,
-     breaking binary compatibility in unexpected ways. Note that this
-     polyfill is *not* recommended and is unsupported.
-
 Most users should be fine sticking with the default. However, if you
 have an existing application which makes heavy use of one of the
 available libraries, you may prefer to build the mongocxx driver

src/bsoncxx/CMakeLists.txt

@@ -21,7 +21,6 @@ set(BSONCXX_VERSION ${BSONCXX_VERSION_NO_EXTRA}${BSONCXX_VERSION_EXTRA})
 message(STATUS "bsoncxx version: ${BSONCXX_VERSION}")
 
 option(BSONCXX_POLY_USE_MNMLSTC "Use MNMLSTC/core for stdx polyfills" OFF)
-option(BSONCXX_POLY_USE_STD_EXPERIMENTAL "Use std::experimental for stdx polyfills" OFF)
 option(BSONCXX_POLY_USE_SYSTEM_MNMLSTC "Obtain mnmlstc/core from system" OFF)
 option(BSONCXX_POLY_USE_BOOST "Use boost for stdx polyfills" OFF)
 option(BSONCXX_POLY_USE_STD "Use C++17 std library for stdx polyfills" OFF)
@@ -31,7 +30,7 @@ set(BSONCXX_OUTPUT_BASENAME "bsoncxx" CACHE STRING "Output bsoncxx library base
 # Count how many polyfill options are true-ish
 set(BSONCXX_POLY_OPTIONS_SET 0)
 
-foreach(BSONCXX_POLY_OPTION ${BSONCXX_POLY_USE_MNMLSTC} ${BSONCXX_POLY_USE_STD_EXPERIMENTAL} ${BSONCXX_POLY_USE_BOOST} ${BSONCXX_POLY_USE_STD})
+foreach(BSONCXX_POLY_OPTION ${BSONCXX_POLY_USE_MNMLSTC} ${BSONCXX_POLY_USE_BOOST} ${BSONCXX_POLY_USE_STD})
     if(${BSONCXX_POLY_OPTION})
         MATH(EXPR BSONCXX_POLY_OPTIONS_SET "${BSONCXX_POLY_OPTIONS_SET}+1")
     endif()
@@ -63,11 +62,6 @@ if(NOT BSONCXX_POLY_USE_MNMLSTC AND BSONCXX_POLY_USE_SYSTEM_MNMLSTC)
     MESSAGE(FATAL_ERROR "Can't specify system mnmlstc when not using mnmlstc")
 endif()
 
-# Can only use STD_EXPERIMENTAL in C++14 mode
-if(BSONCXX_POLY_USE_STD_EXPERIMENTAL AND CMAKE_CXX_STANDARD LESS 14)
-    message(FATAL_ERROR "Can only use BSONCXX_POLY_USE_STD_EXPERIMENTAL if CMAKE_CXX_STANDARD is 14 or higher")
-endif()
-
 set(BSONCXX_BOOST_PKG_DEP "") # Required by bsoncxx-config.cmake.in.
 
 if(BSONCXX_POLY_USE_BOOST)

src/bsoncxx/include/bsoncxx/v_noabi/bsoncxx/config/postlude.hpp

@@ -26,8 +26,6 @@ BSONCXX_POP_WARNINGS();
 #pragma pop_macro("BSONCXX_INLINE_NAMESPACE_END")
 #undef BSONCXX_POLY_USE_MNMLSTC
 #pragma pop_macro("BSONCXX_POLY_USE_MNMLSTC")
-#undef BSONCXX_POLY_USE_STD_EXPERIMENTAL
-#pragma pop_macro("BSONCXX_POLY_USE_STD_EXPERIMENTAL")
 #undef BSONCXX_POLY_USE_SYSTEM_MNMLSTC
 #pragma pop_macro("BSONCXX_POLY_USE_SYSTEM_MNMLSTC")
 #undef BSONCXX_POLY_USE_BOOST

src/bsoncxx/include/bsoncxx/v_noabi/bsoncxx/config/prelude.hpp

@@ -67,8 +67,6 @@
 #undef BSONCXX_INLINE_NAMESPACE_END
 #pragma push_macro("BSONCXX_POLY_USE_MNMLSTC")
 #undef BSONCXX_POLY_USE_MNMLSTC
-#pragma push_macro("BSONCXX_POLY_USE_STD_EXPERIMENTAL")
-#undef BSONCXX_POLY_USE_STD_EXPERIMENTAL
 #pragma push_macro("BSONCXX_POLY_USE_SYSTEM_MNMLSTC")
 #undef BSONCXX_POLY_USE_SYSTEM_MNMLSTC
 #pragma push_macro("BSONCXX_POLY_USE_BOOST")

src/bsoncxx/include/bsoncxx/v_noabi/bsoncxx/stdx/optional.hpp

@@ -54,23 +54,6 @@ using ::boost::make_optional;
 }  // namespace v_noabi
 }  // namespace bsoncxx
 
-#elif defined(BSONCXX_POLY_USE_STD_EXPERIMENTAL)
-
-#include <experimental/optional>
-
-namespace bsoncxx {
-namespace v_noabi {
-namespace stdx {
-
-using ::std::experimental::make_optional;
-using ::std::experimental::nullopt;
-using ::std::experimental::nullopt_t;
-using ::std::experimental::optional;
-
-}  // namespace stdx
-}  // namespace v_noabi
-}  // namespace bsoncxx
-
 #elif defined(BSONCXX_POLY_USE_STD)
 
 #include <optional>

src/bsoncxx/lib/bsoncxx/v_noabi/bsoncxx/config/config.hpp.in

@@ -12,7 +12,6 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-#cmakedefine BSONCXX_POLY_USE_STD_EXPERIMENTAL
 #cmakedefine BSONCXX_POLY_USE_MNMLSTC
 #cmakedefine BSONCXX_POLY_USE_SYSTEM_MNMLSTC
 #cmakedefine BSONCXX_POLY_USE_BOOST

src/bsoncxx/test/CMakeLists.txt

@@ -78,7 +78,6 @@ if(ENABLE_MACRO_GUARD_TESTS)
             BSONCXX_INLINE_NAMESPACE_BEGIN # config.hpp (generated by CMake)
             BSONCXX_INLINE_NAMESPACE_END
             BSONCXX_POLY_USE_MNMLSTC
-            BSONCXX_POLY_USE_STD_EXPERIMENTAL
             BSONCXX_POLY_USE_SYSTEM_MNMLSTC
             BSONCXX_POLY_USE_BOOST
             BSONCXX_VERSION_EXTRA # version.hpp (generated by CMake)