Make bde toolchains up to c++26 ready

Author: osubboo

BdeBuildSystem/toolchains/darwin/clang-bde-presets.cmake

@@ -61,8 +61,12 @@ elseif(BDE_BUILD_TARGET_CPP17)
     set(CMAKE_CXX_STANDARD 17)
 elseif(BDE_BUILD_TARGET_CPP20)
     set(CMAKE_CXX_STANDARD 20)
+elseif(BDE_BUILD_TARGET_CPP23)
+    set(CMAKE_CXX_STANDARD 23)
+elseif(BDE_BUILD_TARGET_CPP26)
+    set(CMAKE_CXX_STANDARD 26)
 else()
-    # c++17 is default on Linux when nothing is set
+    # c++17 is default on Darwin when nothing is set
     set(CMAKE_CXX_STANDARD 17)
 endif()
 

BdeBuildSystem/toolchains/darwin/gcc-bde-presets.cmake

@@ -73,6 +73,8 @@ elseif(BDE_BUILD_TARGET_CPP20)
     set(CMAKE_CXX_STANDARD 20)
 elseif(BDE_BUILD_TARGET_CPP23)
     set(CMAKE_CXX_STANDARD 23)
+elseif(BDE_BUILD_TARGET_CPP26)
+    set(CMAKE_CXX_STANDARD 26)
 else()
     # c++17 is default on Darwing when nothing is set
     set(CMAKE_CXX_STANDARD 17)

BdeBuildSystem/toolchains/sunos/gcc-bde-presets.cmake

@@ -62,6 +62,10 @@ elseif(BDE_BUILD_TARGET_CPP17)
     set(CMAKE_CXX_STANDARD 17)
 elseif(BDE_BUILD_TARGET_CPP20)
     set(CMAKE_CXX_STANDARD 20)
+elseif(BDE_BUILD_TARGET_CPP23)
+    set(CMAKE_CXX_STANDARD 23)
+elseif(BDE_BUILD_TARGET_CPP26)
+    set(CMAKE_CXX_STANDARD 26)
 else()
     # c++03 is default on SunOS
     set(CMAKE_CXX_STANDARD 98)

BdeBuildSystem/toolchains/win32/cl-bde-presets.cmake

@@ -39,6 +39,8 @@ elseif(BDE_BUILD_TARGET_CPP20)
     set(CMAKE_CXX_STANDARD 20)
 elseif(BDE_BUILD_TARGET_CPP23)
     set(CMAKE_CXX_STANDARD 23)
+elseif(BDE_BUILD_TARGET_CPP26)
+    set(CMAKE_CXX_STANDARD 26)
 else()
     # c++17 is default on Windows when nothing is set
     set(CMAKE_CXX_STANDARD 17)