add GCC 13 and 14 to CI

.drone.star

@@ -42,6 +42,8 @@ def main(ctx):
   linux_cxx("gcc 10 cmake-subdirectory", "g++-10", packages="g++-10", image=linuxglobalimage, buildtype="cmake-subdirectory", buildscript="drone", environment={"COMMENT": "cmake-superproject", "CXX": "g++-10"}, globalenv=globalenv),
   linux_cxx("gcc 11", "g++-11", packages="g++-11", buildtype="boost", buildscript="drone", image="cppalliance/droneubuntu2004:1", environment={'B2_TOOLSET': 'gcc-11', 'B2_CXXSTD': '17,2a', 'DRONE_JOB_UUID': '0716d9708d'}, globalenv=globalenv),
   linux_cxx("gcc 12", "g++-12", packages="g++-12", buildtype="boost", buildscript="drone", image="cppalliance/droneubuntu2204:1", environment={'B2_TOOLSET': 'gcc-12', 'B2_CXXSTD': '17,20'}, globalenv=globalenv),
+  linux_cxx("gcc 13", "g++-13", packages="g++-13", buildtype="boost", buildscript="drone", image="cppalliance/droneubuntu2404:1", environment={'B2_TOOLSET': 'gcc-13', 'B2_CXXSTD': '17,20,23'}, globalenv=globalenv),
+  linux_cxx("gcc 14", "g++-14", packages="g++-14", buildtype="boost", buildscript="drone", image="cppalliance/droneubuntu2404:1", environment={'B2_TOOLSET': 'gcc-14', 'B2_CXXSTD': '20'}, globalenv=globalenv),
   linux_cxx("Clang 3.8", "clang++-3.8", packages="clang-3.8 g++", llvm_os='xenial', llvm_ver='3.8', buildtype="boost", buildscript="drone", image="cppalliance/droneubuntu1604:1", environment={'B2_TOOLSET': 'clang-3.8', 'B2_CXXSTD': '11', 'B2_SEPARATE_BOOTSTRAP': '1', 'DRONE_JOB_UUID': 'b3f0c7f6bb'}, globalenv=globalenv),
   linux_cxx("Clang 4.0", "clang++-4.0", packages="clang-4.0 libstdc++-6-dev", llvm_os="xenial", llvm_ver="4.0", buildtype="boost", buildscript="drone", image="cppalliance/droneubuntu1604:1", environment={'B2_TOOLSET': 'clang-4.0', 'B2_CXXSTD': '11,14', 'DRONE_JOB_UUID': '91032ad7bb'}, globalenv=globalenv),
   linux_cxx("Clang 5.0", "clang++-5.0", packages="clang-5.0 libstdc++-7-dev", llvm_os="bionic", llvm_ver="5.0", buildtype="boost", buildscript="drone", image=linuxglobalimage, environment={'B2_TOOLSET': 'clang-5.0', 'B2_CXXSTD': '11,14', 'DRONE_JOB_UUID': '472b07b9fc'}, globalenv=globalenv),

doc/qbk/overview.qbk

@@ -130,8 +130,8 @@ Boost.Endian] in order to support both little endian and big endian platforms.
 
 Boost.JSON has been tested with the following compilers:
 
-* clang: 3.5, 3.6, 3.7, 3.8, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14
-* gcc: 4.8, 4.9, 5, 6, 7, 8, 9, 10, 11, 12
+* clang: 3.8, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15
+* gcc: 4.8, 4.9, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14
 * msvc: 14.0, 14.1, 14.2, 14.3
 
 [important Support for GCC 4.8 and 4.9 is deprecated and will stop in