Use non-const references in non-variadic branch as well

This reverts commit 1a011cde56.

.github/workflows/ci.yml

@@ -42,15 +42,20 @@ jobs:
           - toolset: gcc-8
             cxxstd: "03,11,14,17,2a"
             os: ubuntu-18.04
+            install: g++-8
           - toolset: gcc-9
             cxxstd: "03,11,14,17,2a"
             os: ubuntu-18.04
           - toolset: gcc-10
             cxxstd: "03,11,14,17,2a"
             os: ubuntu-18.04
+          - toolset: gcc-11
+            cxxstd: "03,11,14,17,2a"
+            os: ubuntu-18.04
+            install: g++-11
           - toolset: clang
             compiler: clang++-3.5
-            cxxstd: "03,11,14"
+            cxxstd: "03,11"
             os: ubuntu-16.04
             install: clang-3.5
           - toolset: clang
@@ -87,6 +92,7 @@ jobs:
             compiler: clang++-6.0
             cxxstd: "03,11,14,17"
             os: ubuntu-18.04
+            install: clang-6.0
           - toolset: clang
             compiler: clang++-7
             cxxstd: "03,11,14,17"
@@ -96,14 +102,24 @@ jobs:
             compiler: clang++-8
             cxxstd: "03,11,14,17,2a"
             os: ubuntu-20.04
+            install: clang-8
           - toolset: clang
             compiler: clang++-9
             cxxstd: "03,11,14,17,2a"
             os: ubuntu-20.04
+            install: clang-9
           - toolset: clang
             compiler: clang++-10
             cxxstd: "03,11,14,17,2a"
             os: ubuntu-20.04
+          - toolset: clang
+            compiler: clang++-11
+            cxxstd: "03,11,14,17,2a"
+            os: ubuntu-20.04
+          - toolset: clang
+            compiler: clang++-12
+            cxxstd: "03,11,14,17,2a"
+            os: ubuntu-20.04
           - toolset: clang
             cxxstd: "03,11,14,17,2a"
             os: macos-10.15

.travis.yml

@@ -149,8 +149,9 @@ matrix:
       env: CMAKE_TEST=1
       script:
         - mkdir __build__ && cd __build__
-        - cmake -DBOOST_ENABLE_CMAKE=1 -DBoost_VERBOSE=1 -DBOOST_INCLUDE_LIBRARIES=core ..
-        - ctest --output-on-failure -R boost_core
+        - cmake -DBUILD_TESTING=ON -DBOOST_INCLUDE_LIBRARIES=core ..
+        - cmake --build . --target tests
+        - ctest --output-on-failure
 
     - os: linux
       env: CMAKE_SUBDIR_TEST=1
@@ -168,8 +169,9 @@ matrix:
     - os: linux
       env: CMAKE_INSTALL_TEST=1
       script:
+        - pip install --user cmake
         - mkdir __build__ && cd __build__
-        - cmake -DBOOST_ENABLE_CMAKE=1 -DBoost_VERBOSE=1 -DBOOST_INCLUDE_LIBRARIES="assert;config;core" -DCMAKE_INSTALL_PREFIX=~/.local ..
+        - cmake -DBOOST_INCLUDE_LIBRARIES=core -DCMAKE_INSTALL_PREFIX=~/.local ..
         - cmake --build . --target install
         - cd ../libs/core/test/cmake_install_test && mkdir __build__ && cd __build__
         - cmake -DCMAKE_INSTALL_PREFIX=~/.local ..

CMakeLists.txt

@@ -17,13 +17,6 @@ target_link_libraries(boost_core
     Boost::config
 )
 
-if(BOOST_SUPERPROJECT_VERSION)
-
-  include(BoostInstall)
-  boost_install(TARGETS boost_core HEADER_DIRECTORY include/)
-
-endif()
-
 if(BUILD_TESTING)
 
   add_subdirectory(test)

include/boost/core/ignore_unused.hpp

@@ -11,34 +11,64 @@
 
 namespace boost {
 
-#ifndef BOOST_NO_CXX11_VARIADIC_TEMPLATES
+#if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
+
+#if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
+
+template <typename... Ts>
+BOOST_FORCEINLINE BOOST_CXX14_CONSTEXPR void ignore_unused(Ts&& ...)
+{}
+
+#else
 
 template <typename... Ts>
 BOOST_FORCEINLINE BOOST_CXX14_CONSTEXPR void ignore_unused(Ts const& ...)
 {}
 
+#endif
+
 template <typename... Ts>
 BOOST_FORCEINLINE BOOST_CXX14_CONSTEXPR void ignore_unused()
 {}
 
-#else
+#else // !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
+
+template <typename T1>
+BOOST_FORCEINLINE BOOST_CXX14_CONSTEXPR void ignore_unused(T1&)
+{}
 
 template <typename T1>
 BOOST_FORCEINLINE BOOST_CXX14_CONSTEXPR void ignore_unused(T1 const&)
 {}
 
+template <typename T1, typename T2>
+BOOST_FORCEINLINE BOOST_CXX14_CONSTEXPR void ignore_unused(T1&, T2&)
+{}
+
 template <typename T1, typename T2>
 BOOST_FORCEINLINE BOOST_CXX14_CONSTEXPR void ignore_unused(T1 const&, T2 const&)
 {}
 
+template <typename T1, typename T2, typename T3>
+BOOST_FORCEINLINE BOOST_CXX14_CONSTEXPR void ignore_unused(T1&, T2&, T3&)
+{}
+
 template <typename T1, typename T2, typename T3>
 BOOST_FORCEINLINE BOOST_CXX14_CONSTEXPR void ignore_unused(T1 const&, T2 const&, T3 const&)
 {}
 
+template <typename T1, typename T2, typename T3, typename T4>
+BOOST_FORCEINLINE BOOST_CXX14_CONSTEXPR void ignore_unused(T1&, T2&, T3&, T4&)
+{}
+
 template <typename T1, typename T2, typename T3, typename T4>
 BOOST_FORCEINLINE BOOST_CXX14_CONSTEXPR void ignore_unused(T1 const&, T2 const&, T3 const&, T4 const&)
 {}
 
+template <typename T1, typename T2, typename T3, typename T4, typename T5>
+BOOST_FORCEINLINE BOOST_CXX14_CONSTEXPR void ignore_unused(T1&, T2&, T3&, T4&, T5&)
+{}
+
 template <typename T1, typename T2, typename T3, typename T4, typename T5>
 BOOST_FORCEINLINE BOOST_CXX14_CONSTEXPR void ignore_unused(T1 const&, T2 const&, T3 const&, T4 const&, T5 const&)
 {}

test/Jamfile.v2

@@ -96,7 +96,9 @@ run lightweight_test_test4.cpp
   : : : $(pedantic-errors) ;
 run lightweight_test_test5.cpp
   : : : $(pedantic-errors)
-    <toolset>gcc-4.4.7:<cxxflags>-Wno-sign-compare ;
+    <toolset>gcc-4.4.7:<cxxflags>-Wno-sign-compare
+    <toolset>gcc-4.4:<cxxflags>-Wno-sign-compare
+  ;
 run lightweight_test_test6.cpp
   : : : $(pedantic-errors) ;