Merge topic 'fix-forced-toolchain-dialect'

441dba80 Project: Guess default standard dialect if compiler was forced (#15852)

Modules/Compiler/AppleClang-C.cmake

@@ -18,6 +18,9 @@ if(NOT CMAKE_C_COMPILER_VERSION VERSION_LESS 4.0)
       message(FATAL_ERROR "CMAKE_C_STANDARD_COMPUTED_DEFAULT should be set for ${CMAKE_C_COMPILER_ID} (${CMAKE_C_COMPILER}) version ${CMAKE_C_COMPILER_VERSION}")
     endif()
     set(CMAKE_C_STANDARD_DEFAULT ${CMAKE_C_STANDARD_COMPUTED_DEFAULT})
+  elseif(NOT DEFINED CMAKE_C_STANDARD_DEFAULT)
+    # Compiler id was forced so just guess the default standard level.
+    set(CMAKE_C_STANDARD_DEFAULT 99)
   endif()
 endif()
 

Modules/Compiler/AppleClang-CXX.cmake

@@ -28,6 +28,9 @@ if(NOT CMAKE_CXX_COMPILER_VERSION VERSION_LESS 4.0)
       message(FATAL_ERROR "CMAKE_CXX_STANDARD_COMPUTED_DEFAULT should be set for ${CMAKE_CXX_COMPILER_ID} (${CMAKE_CXX_COMPILER}) version ${CMAKE_CXX_COMPILER_VERSION}")
     endif()
     set(CMAKE_CXX_STANDARD_DEFAULT ${CMAKE_CXX_STANDARD_COMPUTED_DEFAULT})
+  elseif(NOT DEFINED CMAKE_CXX_STANDARD_DEFAULT)
+    # Compiler id was forced so just guess the default standard level.
+    set(CMAKE_CXX_STANDARD_DEFAULT 98)
   endif()
 endif()
 

Modules/Compiler/Clang-C.cmake

@@ -23,6 +23,13 @@ if(NOT CMAKE_C_COMPILER_VERSION VERSION_LESS 3.4)
       message(FATAL_ERROR "CMAKE_C_STANDARD_COMPUTED_DEFAULT should be set for ${CMAKE_C_COMPILER_ID} (${CMAKE_C_COMPILER}) version ${CMAKE_C_COMPILER_VERSION}")
     endif()
     set(CMAKE_C_STANDARD_DEFAULT ${CMAKE_C_STANDARD_COMPUTED_DEFAULT})
+  elseif(NOT DEFINED CMAKE_C_STANDARD_DEFAULT)
+    # Compiler id was forced so just guess the default standard level.
+    if (NOT CMAKE_C_COMPILER_VERSION VERSION_LESS 3.6)
+      set(CMAKE_C_STANDARD_DEFAULT 11)
+    else()
+      set(CMAKE_C_STANDARD_DEFAULT 99)
+    endif()
   endif()
 endif()
 

Modules/Compiler/Clang-CXX.cmake

@@ -37,6 +37,9 @@ if(NOT CMAKE_CXX_COMPILER_VERSION VERSION_LESS 3.4)
       message(FATAL_ERROR "CMAKE_CXX_STANDARD_COMPUTED_DEFAULT should be set for ${CMAKE_CXX_COMPILER_ID} (${CMAKE_CXX_COMPILER}) version ${CMAKE_CXX_COMPILER_VERSION}")
     endif()
     set(CMAKE_CXX_STANDARD_DEFAULT ${CMAKE_CXX_STANDARD_COMPUTED_DEFAULT})
+  elseif(NOT DEFINED CMAKE_CXX_STANDARD_DEFAULT)
+    # Compiler id was forced so just guess the default standard level.
+    set(CMAKE_CXX_STANDARD_DEFAULT 98)
   endif()
 endif()
 

Modules/Compiler/GNU-C.cmake

@@ -28,6 +28,13 @@ if(NOT CMAKE_C_COMPILER_VERSION VERSION_LESS 4.4)
       message(FATAL_ERROR "CMAKE_C_STANDARD_COMPUTED_DEFAULT should be set for ${CMAKE_C_COMPILER_ID} (${CMAKE_C_COMPILER}) version ${CMAKE_C_COMPILER_VERSION}")
     endif()
     set(CMAKE_C_STANDARD_DEFAULT ${CMAKE_C_STANDARD_COMPUTED_DEFAULT})
+  elseif(NOT DEFINED CMAKE_C_STANDARD_DEFAULT)
+    # Compiler id was forced so just guess the default standard level.
+    if (NOT CMAKE_C_COMPILER_VERSION VERSION_LESS 5.0)
+      set(CMAKE_C_STANDARD_DEFAULT 11)
+    else()
+      set(CMAKE_C_STANDARD_DEFAULT 90)
+    endif()
   endif()
 endif()
 

Modules/Compiler/GNU-CXX.cmake

@@ -40,6 +40,9 @@ if(NOT CMAKE_CXX_COMPILER_VERSION VERSION_LESS 4.4)
       message(FATAL_ERROR "CMAKE_CXX_STANDARD_COMPUTED_DEFAULT should be set for ${CMAKE_CXX_COMPILER_ID} (${CMAKE_CXX_COMPILER}) version ${CMAKE_CXX_COMPILER_VERSION}")
     endif()
     set(CMAKE_CXX_STANDARD_DEFAULT ${CMAKE_CXX_STANDARD_COMPUTED_DEFAULT})
+  elseif(NOT DEFINED CMAKE_CXX_STANDARD_DEFAULT)
+    # Compiler id was forced so just guess the default standard level.
+    set(CMAKE_CXX_STANDARD_DEFAULT 98)
   endif()
 endif()
 

Modules/Compiler/SunPro-CXX.cmake

@@ -42,6 +42,9 @@ if(NOT CMAKE_CXX_COMPILER_VERSION VERSION_LESS 5.13)
       message(FATAL_ERROR "CMAKE_CXX_STANDARD_COMPUTED_DEFAULT should be set for ${CMAKE_CXX_COMPILER_ID} (${CMAKE_CXX_COMPILER}) version ${CMAKE_CXX_COMPILER_VERSION}")
     endif()
     set(CMAKE_CXX_STANDARD_DEFAULT ${CMAKE_CXX_STANDARD_COMPUTED_DEFAULT})
+  elseif(NOT DEFINED CMAKE_CXX_STANDARD_DEFAULT)
+    # Compiler id was forced so just guess the default standard level.
+    set(CMAKE_CXX_STANDARD_DEFAULT 98)
   endif()
 endif()