WCDH: Remove noise from generated defines.

The DECL part is redundant, and the language part is not needed. The
source language and context already determines the language, so there
is no need to repeat it in the define name.

Help/manual/cmake-compile-features.7.rst

@@ -166,11 +166,11 @@ symbol, and compiler support determines what it is expanded to:
     virtual void Execute() = 0;
   };
 
-  struct Concrete Foo_CXX_FINAL {
-    void Execute() Foo_CXX_OVERRIDE;
+  struct Concrete Foo_FINAL {
+    void Execute() Foo_OVERRIDE;
   };
 
-In this case, ``Foo_CXX_FINAL`` will expand to ``final`` if the
+In this case, ``Foo_FINAL`` will expand to ``final`` if the
 compiler supports the keyword, or to empty otherwise.
 
 In this use-case, the CMake code will wish to enable a particular language
@@ -189,13 +189,13 @@ set to influence all following targets:
       cxx_final cxx_override
   )
 
-  # Includes foo_compiler_detection.h and uses the Foo_DECL_CXX_FINAL symbol
+  # Includes foo_compiler_detection.h and uses the Foo_FINAL symbol
   # which will expand to 'final' if the compiler supports the requested
   # CXX_STANDARD.
   add_library(foo foo.cpp)
   set_property(TARGET foo PROPERTY CXX_STANDARD 11)
 
-  # Includes foo_compiler_detection.h and uses the Foo_DECL_CXX_FINAL symbol
+  # Includes foo_compiler_detection.h and uses the Foo_FINAL symbol
   # which will expand to 'final' if the compiler supports the feature,
   # even though CXX_STANDARD is not set explicitly.  The requirement of
   # cxx_constexpr causes CMake to set CXX_STANDARD internally, which

Modules/WriteCompilerDetectionHeader.cmake

@@ -99,14 +99,14 @@
 #
 # .. code-block:: c++
 #
-#    class MyClass ClimbingStats_DECL_CXX_FINAL
+#    class MyClass ClimbingStats_FINAL
 #    {
-#        ClimbingStats_DECL_CXX_CONSTEXPR int someInterface() { return 42; }
+#        ClimbingStats_CONSTEXPR int someInterface() { return 42; }
 #    };
 #
-# The ``ClimbingStats_DECL_CXX_FINAL`` macro will expand to ``final`` if the
+# The ``ClimbingStats_FINAL`` macro will expand to ``final`` if the
 # compiler (and its flags) support the ``cxx_final`` feature, and the
-# ``ClimbingStats_DECL_CXX_CONSTEXPR`` macro will expand to ``constexpr``
+# ``ClimbingStats_CONSTEXPR`` macro will expand to ``constexpr``
 # if ``cxx_constexpr`` is supported.
 #
 # The following features generate corresponding symbol defines:
@@ -386,7 +386,7 @@ function(write_compiler_detection_header
 \n")
       endif()
       if (feature STREQUAL cxx_constexpr)
-        set(def_value "${prefix_arg}_DECL_${feature_upper}")
+        set(def_value "${prefix_arg}_CONSTEXPR")
         set(file_content "${file_content}
 #  if ${def_name}
 #    define ${def_value} constexpr
@@ -396,7 +396,7 @@ function(write_compiler_detection_header
 \n")
       endif()
       if (feature STREQUAL cxx_final)
-        set(def_value "${prefix_arg}_DECL_${feature_upper}")
+        set(def_value "${prefix_arg}_FINAL")
         set(file_content "${file_content}
 #  if ${def_name}
 #    define ${def_value} final
@@ -406,7 +406,7 @@ function(write_compiler_detection_header
 \n")
       endif()
       if (feature STREQUAL cxx_override)
-        set(def_value "${prefix_arg}_DECL_${feature_upper}")
+        set(def_value "${prefix_arg}_OVERRIDE")
         set(file_content "${file_content}
 #  if ${def_name}
 #    define ${def_value} override