Modules: Do not implicitly add new functions via old Check Modules

The conversion of Check<Lang>CompilerFlag, SourceCompiles, and
SourceRuns over to the new functions has the possibility of breaking
projects that had functions with those existing names.

To reduce the possibility of collisions we now have all the
legacy code call functions that start with `cmake_`, and users
will need to explicitly include the new modules to get the
non-prefixed versions

Fixes: #21359

1 files changed, 127 insertions, 0 deletions

diff --git a/Modules/Internal/CheckSourceCompiles.cmake b/Modules/Internal/CheckSourceCompiles.cmake
new file mode 100644
index 0000000000..91c89640f3
--- /dev/null
+++ b/Modules/Internal/CheckSourceCompiles.cmake
@@ -0,0 +1,127 @@
+# Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
+# file Copyright.txt or https://cmake.org/licensing for details.
+
+include_guard(GLOBAL)
+
+cmake_policy(PUSH)
+cmake_policy(SET CMP0054 NEW) # if() quoted variables not dereferenced
+cmake_policy(SET CMP0057 NEW) # if() supports IN_LIST
+
+function(CMAKE_CHECK_SOURCE_COMPILES _lang _source _var)
+  if(NOT DEFINED "${_var}")
+
+    if(_lang STREQUAL C)
+      set(_lang_textual "C")
+      set(_lang_ext "c")
+    elseif(_lang STREQUAL CXX)
+      set(_lang_textual "C++")
+      set(_lang_ext "cxx")
+    elseif(_lang STREQUAL CUDA)
+      set(_lang_textual "CUDA")
+      set(_lang_ext "cu")
+    elseif(_lang STREQUAL Fortran)
+      set(_lang_textual "Fortran")
+      set(_lang_ext "F90")
+    elseif(_lang STREQUAL ISPC)
+      set(_lang_textual "ISPC")
+      set(_lang_ext "ispc")
+    elseif(_lang STREQUAL OBJC)
+      set(_lang_textual "Objective-C")
+      set(_lang_ext "m")
+    elseif(_lang STREQUAL OBJCXX)
+      set(_lang_textual "Objective-C++")
+      set(_lang_ext "mm")
+    else()
+      message (SEND_ERROR "check_source_compiles: ${_lang}: unknown language.")
+      return()
+    endif()
+
+    get_property (_supported_languages GLOBAL PROPERTY ENABLED_LANGUAGES)
+    if (NOT _lang IN_LIST _supported_languages)
+      message (SEND_ERROR "check_source_compiles: ${_lang}: needs to be enabled before use.")
+      return()
+    endif()
+
+    set(_FAIL_REGEX)
+    set(_SRC_EXT)
+    set(_key)
+    foreach(arg ${ARGN})
+      if("${arg}" MATCHES "^(FAIL_REGEX|SRC_EXT)$")
+        set(_key "${arg}")
+      elseif(_key STREQUAL "FAIL_REGEX")
+        list(APPEND _FAIL_REGEX "${arg}")
+      elseif(_key STREQUAL "SRC_EXT")
+        set(_SRC_EXT "${arg}")
+        set(_key "")
+      else()
+        message(FATAL_ERROR "Unknown argument:\n  ${arg}\n")
+      endif()
+    endforeach()
+
+    if(NOT _SRC_EXT)
+      set(_SRC_EXT ${_lang_ext})
+    endif()
+
+    if(CMAKE_REQUIRED_LINK_OPTIONS)
+      set(CHECK_${LANG}_SOURCE_COMPILES_ADD_LINK_OPTIONS
+        LINK_OPTIONS ${CMAKE_REQUIRED_LINK_OPTIONS})
+    else()
+      set(CHECK_${LANG}_SOURCE_COMPILES_ADD_LINK_OPTIONS)
+    endif()
+    if(CMAKE_REQUIRED_LIBRARIES)
+      set(CHECK_${LANG}_SOURCE_COMPILES_ADD_LIBRARIES
+        LINK_LIBRARIES ${CMAKE_REQUIRED_LIBRARIES})
+    else()
+      set(CHECK_${LANG}_SOURCE_COMPILES_ADD_LIBRARIES)
+    endif()
+    if(CMAKE_REQUIRED_INCLUDES)
+      set(CHECK_${LANG}_SOURCE_COMPILES_ADD_INCLUDES
+        "-DINCLUDE_DIRECTORIES:STRING=${CMAKE_REQUIRED_INCLUDES}")
+    else()
+      set(CHECK_${LANG}_SOURCE_COMPILES_ADD_INCLUDES)
+    endif()
+    file(WRITE "${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeTmp/src.${_SRC_EXT}"
+      "${_source}\n")
+
+    if(NOT CMAKE_REQUIRED_QUIET)
+      message(CHECK_START "Performing Test ${_var}")
+    endif()
+    try_compile(${_var}
+      ${CMAKE_BINARY_DIR}
+      ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeTmp/src.${_SRC_EXT}
+      COMPILE_DEFINITIONS -D${_var} ${CMAKE_REQUIRED_DEFINITIONS}
+      ${CHECK_${LANG}_SOURCE_COMPILES_ADD_LINK_OPTIONS}
+      ${CHECK_${LANG}_SOURCE_COMPILES_ADD_LIBRARIES}
+      CMAKE_FLAGS -DCOMPILE_DEFINITIONS:STRING=${CMAKE_REQUIRED_FLAGS}
+      "${CHECK_${LANG}_SOURCE_COMPILES_ADD_INCLUDES}"
+      OUTPUT_VARIABLE OUTPUT)
+
+    foreach(_regex ${_FAIL_REGEX})
+      if("${OUTPUT}" MATCHES "${_regex}")
+        set(${_var} 0)
+      endif()
+    endforeach()
+
+    if(${_var})
+      set(${_var} 1 CACHE INTERNAL "Test ${_var}")
+      if(NOT CMAKE_REQUIRED_QUIET)
+        message(CHECK_PASS "Success")
+      endif()
+      file(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeOutput.log
+        "Performing ${_lang_textual} SOURCE FILE Test ${_var} succeeded with the following output:\n"
+        "${OUTPUT}\n"
+        "Source file was:\n${_source}\n")
+    else()
+      if(NOT CMAKE_REQUIRED_QUIET)
+        message(CHECK_FAIL "Failed")
+      endif()
+      set(${_var} "" CACHE INTERNAL "Test ${_var}")
+      file(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeError.log
+        "Performing ${_lang_textual} SOURCE FILE Test ${_var} failed with the following output:\n"
+        "${OUTPUT}\n"
+        "Source file was:\n${_source}\n")
+    endif()
+  endif()
+endfunction()
+
+cmake_policy(POP)