Only initialize CMAKE_CXX_COMPILER_PREDEFINES_COMMAND

Don't initialize the other CMAKE_<LANG>_COMPILER_PREDEFINES_COMMAND
variables.

The only language variant that is used is
CMAKE_CXX_COMPILER_PREDEFINES_COMMAND, and the other language variants
contained invalid, namely C++-specific commands.

Fixes: #23968

Modules/Compiler/Clang.cmake

@@ -44,7 +44,7 @@ else()
     set(CMAKE_${lang}_LINKER_WRAPPER_FLAG "-Xlinker" " ")
     set(CMAKE_${lang}_LINKER_WRAPPER_FLAG_SEP)
 
-    if(CMAKE_${lang}_COMPILER_TARGET)
+    if(CMAKE_${lang}_COMPILER_TARGET AND "${lang}" STREQUAL "CXX")
       if(CMAKE_${lang}_COMPILER_VERSION VERSION_LESS 3.4.0)
         list(APPEND CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND "-target" "${CMAKE_${lang}_COMPILER_TARGET}")
       else()

Modules/Compiler/GNU.cmake

@@ -121,13 +121,15 @@ macro(__compiler_gnu lang)
     )
   endif()
 
-  set(CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND "${CMAKE_${lang}_COMPILER}")
-  if(CMAKE_${lang}_COMPILER_ARG1)
-    separate_arguments(_COMPILER_ARGS NATIVE_COMMAND "${CMAKE_${lang}_COMPILER_ARG1}")
-    list(APPEND CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND ${_COMPILER_ARGS})
-    unset(_COMPILER_ARGS)
+  if("${lang}" STREQUAL "CXX")
+    set(CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND "${CMAKE_${lang}_COMPILER}")
+    if(CMAKE_${lang}_COMPILER_ARG1)
+      separate_arguments(_COMPILER_ARGS NATIVE_COMMAND "${CMAKE_${lang}_COMPILER_ARG1}")
+      list(APPEND CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND ${_COMPILER_ARGS})
+      unset(_COMPILER_ARGS)
+    endif()
+    list(APPEND CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND "-dM" "-E" "-c" "${CMAKE_ROOT}/Modules/CMakeCXXCompilerABI.cpp")
   endif()
-  list(APPEND CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND "-dM" "-E" "-c" "${CMAKE_ROOT}/Modules/CMakeCXXCompilerABI.cpp")
 
   if(NOT "x${lang}" STREQUAL "xFortran")
     set(CMAKE_PCH_EXTENSION .gch)

Modules/Compiler/IBMClang.cmake

@@ -36,7 +36,7 @@ macro(__compiler_ibmclang lang)
   set(CMAKE_${lang}_LINKER_WRAPPER_FLAG "-Xlinker" " ")
   set(CMAKE_${lang}_LINKER_WRAPPER_FLAG_SEP)
 
-  if(CMAKE_${lang}_COMPILER_TARGET)
+  if(CMAKE_${lang}_COMPILER_TARGET AND "${lang}" STREQUAL "CXX")
     list(APPEND CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND "--target=${CMAKE_${lang}_COMPILER_TARGET}")
   endif()
 
@@ -66,7 +66,9 @@ macro(__compiler_ibmclang lang)
     "\"${__ranlib}\" <TARGET>"
   )
 
-  list(APPEND CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND "-dM" "-E" "-c" "${CMAKE_ROOT}/Modules/CMakeCXXCompilerABI.cpp")
+  if("${lang}" STREQUAL "CXX")
+    list(APPEND CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND "-dM" "-E" "-c" "${CMAKE_ROOT}/Modules/CMakeCXXCompilerABI.cpp")
+  endif()
 
   set(CMAKE_PCH_EXTENSION .pch)
 

Modules/Compiler/Intel.cmake

@@ -30,13 +30,15 @@ else()
     string(APPEND CMAKE_${lang}_FLAGS_RELEASE_INIT " -O3")
     string(APPEND CMAKE_${lang}_FLAGS_RELWITHDEBINFO_INIT " -O2 -g")
 
-    set(CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND "${CMAKE_${lang}_COMPILER}")
-    if(CMAKE_${lang}_COMPILER_ARG1)
-      separate_arguments(_COMPILER_ARGS NATIVE_COMMAND "${CMAKE_${lang}_COMPILER_ARG1}")
-      list(APPEND CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND ${_COMPILER_ARGS})
-      unset(_COMPILER_ARGS)
+    if("${lang}" STREQUAL "CXX")
+      set(CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND "${CMAKE_${lang}_COMPILER}")
+      if(CMAKE_${lang}_COMPILER_ARG1)
+        separate_arguments(_COMPILER_ARGS NATIVE_COMMAND "${CMAKE_${lang}_COMPILER_ARG1}")
+        list(APPEND CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND ${_COMPILER_ARGS})
+        unset(_COMPILER_ARGS)
+      endif()
+      list(APPEND CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND "-QdM" "-P" "-Za" "${CMAKE_ROOT}/Modules/CMakeCXXCompilerABI.cpp")
     endif()
-    list(APPEND CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND "-QdM" "-P" "-Za" "${CMAKE_ROOT}/Modules/CMakeCXXCompilerABI.cpp")
 
     if("x${lang}" STREQUAL "xFortran")
       set(CMAKE_${lang}_COMPILE_OPTIONS_WARNING_AS_ERROR "-warn" "errors")

Modules/Compiler/IntelLLVM.cmake

@@ -80,15 +80,17 @@ else()
     set(CMAKE_${lang}_CREATE_PREPROCESSED_SOURCE "<CMAKE_${lang}_COMPILER> <DEFINES> <INCLUDES> <FLAGS> -E <SOURCE> > <PREPROCESSED_SOURCE>")
     set(CMAKE_${lang}_CREATE_ASSEMBLY_SOURCE "<CMAKE_${lang}_COMPILER> <DEFINES> <INCLUDES> <FLAGS> -S <SOURCE> -o <ASSEMBLY_SOURCE>")
 
-    set(CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND "${CMAKE_${lang}_COMPILER}")
-    if(CMAKE_${lang}_COMPILER_ARG1)
-      separate_arguments(_COMPILER_ARGS NATIVE_COMMAND "${CMAKE_${lang}_COMPILER_ARG1}")
-      list(APPEND CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND ${_COMPILER_ARGS})
-      unset(_COMPILER_ARGS)
-    endif()
-    list(APPEND CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND "-dM" "-E" "-c" "${CMAKE_ROOT}/Modules/CMakeCXXCompilerABI.cpp")
-    if(CMAKE_${lang}_COMPILER_TARGET)
-      list(APPEND CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND "--target=${CMAKE_${lang}_COMPILER_TARGET}")
+    if("${lang}" STREQUAL "CXX")
+      set(CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND "${CMAKE_${lang}_COMPILER}")
+      if(CMAKE_${lang}_COMPILER_ARG1)
+        separate_arguments(_COMPILER_ARGS NATIVE_COMMAND "${CMAKE_${lang}_COMPILER_ARG1}")
+        list(APPEND CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND ${_COMPILER_ARGS})
+        unset(_COMPILER_ARGS)
+      endif()
+      list(APPEND CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND "-dM" "-E" "-c" "${CMAKE_ROOT}/Modules/CMakeCXXCompilerABI.cpp")
+      if(CMAKE_${lang}_COMPILER_TARGET)
+        list(APPEND CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND "--target=${CMAKE_${lang}_COMPILER_TARGET}")
+      endif()
     endif()
 
     if("x${lang}" STREQUAL "xFortran")

Modules/Compiler/LCC.cmake

@@ -76,13 +76,15 @@ macro(__compiler_lcc lang)
     "\"${CMAKE_${lang}_COMPILER_RANLIB}\" <TARGET>"
   )
 
-  set(CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND "${CMAKE_${lang}_COMPILER}")
-  if(CMAKE_${lang}_COMPILER_ARG1)
-    separate_arguments(_COMPILER_ARGS NATIVE_COMMAND "${CMAKE_${lang}_COMPILER_ARG1}")
-    list(APPEND CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND ${_COMPILER_ARGS})
-    unset(_COMPILER_ARGS)
+  if("${lang}" STREQUAL "CXX")
+    set(CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND "${CMAKE_${lang}_COMPILER}")
+    if(CMAKE_${lang}_COMPILER_ARG1)
+      separate_arguments(_COMPILER_ARGS NATIVE_COMMAND "${CMAKE_${lang}_COMPILER_ARG1}")
+      list(APPEND CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND ${_COMPILER_ARGS})
+      unset(_COMPILER_ARGS)
+    endif()
+    list(APPEND CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND "-dM" "-E" "-c" "${CMAKE_ROOT}/Modules/CMakeCXXCompilerABI.cpp")
   endif()
-  list(APPEND CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND "-dM" "-E" "-c" "${CMAKE_ROOT}/Modules/CMakeCXXCompilerABI.cpp")
 
   if(NOT "x${lang}" STREQUAL "xFortran")
     set(CMAKE_PCH_EXTENSION .gch)

Modules/Compiler/QCC.cmake

@@ -22,13 +22,15 @@ macro(__compiler_qcc lang)
   set(_CMAKE_${lang}_IPO_SUPPORTED_BY_CMAKE NO)
   set(_CMAKE_${lang}_IPO_MAY_BE_SUPPORTED_BY_COMPILER NO)
 
-  set(CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND "${CMAKE_${lang}_COMPILER}")
-  if(CMAKE_${lang}_COMPILER_ARG1)
-    separate_arguments(_COMPILER_ARGS NATIVE_COMMAND "${CMAKE_${lang}_COMPILER_ARG1}")
-    list(APPEND CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND ${_COMPILER_ARGS})
-    unset(_COMPILER_ARGS)
+  if("${lang}" STREQUAL "CXX")
+    set(CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND "${CMAKE_${lang}_COMPILER}")
+    if(CMAKE_${lang}_COMPILER_ARG1)
+      separate_arguments(_COMPILER_ARGS NATIVE_COMMAND "${CMAKE_${lang}_COMPILER_ARG1}")
+      list(APPEND CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND ${_COMPILER_ARGS})
+      unset(_COMPILER_ARGS)
+    endif()
+    list(APPEND CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND "-Wp,-dM" "-E" "-c" "${CMAKE_ROOT}/Modules/CMakeCXXCompilerABI.cpp")
   endif()
-  list(APPEND CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND "-Wp,-dM" "-E" "-c" "${CMAKE_ROOT}/Modules/CMakeCXXCompilerABI.cpp")
 
   unset(CMAKE_${lang}_COMPILE_OPTIONS_IPO)
   unset(CMAKE_${lang}_ARCHIVE_CREATE_IPO)

Modules/Compiler/Tasking.cmake

@@ -43,12 +43,14 @@ macro(__compiler_tasking lang)
   set(CMAKE_${lang}_CREATE_ASSEMBLY_SOURCE "<CMAKE_${lang}_COMPILER> <DEFINES> <INCLUDES> <FLAGS> -cs <SOURCE> -o <ASSEMBLY_SOURCE>")
   set(CMAKE_${lang}_CREATE_PREPROCESSED_SOURCE "<CMAKE_${lang}_COMPILER> <DEFINES> <INCLUDES> <FLAGS> -Ep <SOURCE> > <PREPROCESSED_SOURCE>")
 
-  set(CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND "${CMAKE_${lang}_COMPILER}")
-  if(CMAKE_${lang}_COMPILER_ARG1)
-    separate_arguments(_COMPILER_ARGS NATIVE_COMMAND "${CMAKE_${lang}_COMPILER_ARG1}")
-    list(APPEND CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND ${_COMPILER_ARGS})
-    unset(_COMPILER_ARGS)
+  if("${lang}" STREQUAL "CXX")
+    set(CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND "${CMAKE_${lang}_COMPILER}")
+    if(CMAKE_${lang}_COMPILER_ARG1)
+      separate_arguments(_COMPILER_ARGS NATIVE_COMMAND "${CMAKE_${lang}_COMPILER_ARG1}")
+      list(APPEND CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND ${_COMPILER_ARGS})
+      unset(_COMPILER_ARGS)
+    endif()
+    list(APPEND CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND "-Ep" "${CMAKE_ROOT}/Modules/CMakeCXXCompilerABI.cpp")
   endif()
-  list(APPEND CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND "-Ep" "${CMAKE_ROOT}/Modules/CMakeCXXCompilerABI.cpp")
 
 endmacro()

Modules/Platform/Android-Clang.cmake

@@ -77,7 +77,9 @@ macro(__android_compiler_clang lang)
     if(CMAKE_ANDROID_NDK_TOOLCHAIN_UNIFIED)
       string(APPEND CMAKE_${lang}_COMPILER_TARGET "${CMAKE_SYSTEM_VERSION}")
     endif()
-    list(APPEND CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND "--target=${CMAKE_${lang}_COMPILER_TARGET}")
+    if("${lang}" STREQUAL "CXX")
+      list(APPEND CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND "--target=${CMAKE_${lang}_COMPILER_TARGET}")
+    endif()
   endif()
   if(CMAKE_GENERATOR MATCHES "Visual Studio")
     set(_ANDROID_STL_NOSTDLIBXX 1)