Modules: Use new SOURCES_FROM_* try_compile (1/2)

Modify some modules that ship with CMake to use the new SOURCES_FROM_*
arguments to try_compile / try_run as added by commits cb14ae2b87
(try_compile: Add SOURCE_FROM_{ARG,VAR}, 2022-09-21) and 611d801790
(try_compile: Add SOURCE_FROM_FILE, 2022-09-22). This covers users which
previously either used an existing file (but sometimes needed to rename
it), or which wrote out their source in entirety. It does NOT cover
users that actually need configure_file functionality, as those will be
more involved to update and will thus be tackled in part 2.

1 files changed, 12 insertions, 15 deletions

diff --git a/Modules/CheckSymbolExists.cmake b/Modules/CheckSymbolExists.cmake
index ebaeb7c..0d44d56 100644
--- a/Modules/CheckSymbolExists.cmake
+++ b/Modules/CheckSymbolExists.cmake
@@ -68,11 +68,11 @@ cmake_policy(SET CMP0054 NEW) # if() quoted variables not dereferenced
 macro(CHECK_SYMBOL_EXISTS SYMBOL FILES VARIABLE)
   if(CMAKE_C_COMPILER_LOADED)
     __CHECK_SYMBOL_EXISTS_FILTER_FLAGS(C)
-    __CHECK_SYMBOL_EXISTS_IMPL("${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeTmp/CheckSymbolExists.c" "${SYMBOL}" "${FILES}" "${VARIABLE}" )
+    __CHECK_SYMBOL_EXISTS_IMPL(CheckSymbolExists.c "${SYMBOL}" "${FILES}" "${VARIABLE}" )
     __CHECK_SYMBOL_EXISTS_RESTORE_FLAGS(C)
   elseif(CMAKE_CXX_COMPILER_LOADED)
     __CHECK_SYMBOL_EXISTS_FILTER_FLAGS(CXX)
-    __CHECK_SYMBOL_EXISTS_IMPL("${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeTmp/CheckSymbolExists.cxx" "${SYMBOL}" "${FILES}" "${VARIABLE}" )
+    __CHECK_SYMBOL_EXISTS_IMPL(CheckSymbolExists.cxx "${SYMBOL}" "${FILES}" "${VARIABLE}" )
     __CHECK_SYMBOL_EXISTS_RESTORE_FLAGS(CXX)
   else()
     message(FATAL_ERROR "CHECK_SYMBOL_EXISTS needs either C or CXX language enabled")
@@ -92,7 +92,7 @@ endmacro()
 
 macro(__CHECK_SYMBOL_EXISTS_IMPL SOURCEFILE SYMBOL FILES VARIABLE)
   if(NOT DEFINED "${VARIABLE}" OR "x${${VARIABLE}}" STREQUAL "x${VARIABLE}")
-    set(CMAKE_CONFIGURABLE_FILE_CONTENT "/* */\n")
+    set(_CSE_SOURCE "/* */\n")
     set(MACRO_CHECK_SYMBOL_EXISTS_FLAGS ${CMAKE_REQUIRED_FLAGS})
     if(CMAKE_REQUIRED_LINK_OPTIONS)
       set(CHECK_SYMBOL_EXISTS_LINK_OPTIONS
@@ -113,17 +113,17 @@ macro(__CHECK_SYMBOL_EXISTS_IMPL SOURCEFILE SYMBOL FILES VARIABLE)
       set(CMAKE_SYMBOL_EXISTS_INCLUDES)
     endif()
     foreach(FILE ${FILES})
-      string(APPEND CMAKE_CONFIGURABLE_FILE_CONTENT
+      string(APPEND _CSE_SOURCE
         "#include <${FILE}>\n")
     endforeach()
-    string(APPEND CMAKE_CONFIGURABLE_FILE_CONTENT "
+    string(APPEND _CSE_SOURCE "
 int main(int argc, char** argv)
 {
   (void)argv;")
     set(_CSE_CHECK_NON_MACRO "return ((int*)(&${SYMBOL}))[argc];")
     if("${SYMBOL}" MATCHES "^[a-zA-Z_][a-zA-Z0-9_]*$")
       # The SYMBOL has a legal macro name.  Test whether it exists as a macro.
-      string(APPEND CMAKE_CONFIGURABLE_FILE_CONTENT "
+      string(APPEND _CSE_SOURCE "
 #ifndef ${SYMBOL}
   ${_CSE_CHECK_NON_MACRO}
 #else
@@ -132,21 +132,18 @@ int main(int argc, char** argv)
 #endif")
     else()
       # The SYMBOL cannot be a macro (e.g., a template function).
-      string(APPEND CMAKE_CONFIGURABLE_FILE_CONTENT "
+      string(APPEND _CSE_SOURCE "
   ${_CSE_CHECK_NON_MACRO}")
     endif()
-    string(APPEND CMAKE_CONFIGURABLE_FILE_CONTENT "
+    string(APPEND _CSE_SOURCE "
 }")
     unset(_CSE_CHECK_NON_MACRO)
 
-    configure_file("${CMAKE_ROOT}/Modules/CMakeConfigurableFile.in"
-      "${SOURCEFILE}" @ONLY)
-
     if(NOT CMAKE_REQUIRED_QUIET)
       message(CHECK_START "Looking for ${SYMBOL}")
     endif()
     try_compile(${VARIABLE}
-      SOURCES "${SOURCEFILE}"
+      SOURCE_FROM_VAR "${SOURCEFILE}" _CSE_SOURCE
       COMPILE_DEFINITIONS ${CMAKE_REQUIRED_DEFINITIONS}
       ${CHECK_SYMBOL_EXISTS_LINK_OPTIONS}
       ${CHECK_SYMBOL_EXISTS_LIBS}
@@ -163,7 +160,7 @@ int main(int argc, char** argv)
         "Determining if the ${SYMBOL} "
         "exist passed with the following output:\n"
         "${OUTPUT}\nFile ${SOURCEFILE}:\n"
-        "${CMAKE_CONFIGURABLE_FILE_CONTENT}\n")
+        "${_CSE_SOURCE}\n")
     else()
       if(NOT CMAKE_REQUIRED_QUIET)
         message(CHECK_FAIL "not found")
@@ -173,9 +170,9 @@ int main(int argc, char** argv)
         "Determining if the ${SYMBOL} "
         "exist failed with the following output:\n"
         "${OUTPUT}\nFile ${SOURCEFILE}:\n"
-        "${CMAKE_CONFIGURABLE_FILE_CONTENT}\n")
+        "${_CSE_SOURCE}\n")
     endif()
-    unset(CMAKE_CONFIGURABLE_FILE_CONTENT)
+    unset(_CSE_SOURCE)
   endif()
 endmacro()