Adapting HPX modules from level 12 to C++ modules

- flyby: fixing propagation of SCAN_FOR_MODULES to HPX targets

Signed-off-by: Hartmut Kaiser <hartmut.kaiser@gmail.com>

Author: hkaiser

CMakeLists.txt

@@ -331,16 +331,7 @@ if(HPX_WITH_CXX_MODULES)
   )
   hpx_add_config_define(HPX_HAVE_CXX_MODULES)
 
-  hpx_option(
-    HPX_WITH_BUILD_USING_CXX_MODULES
-    BOOL
-    "Enable building HPX itself using C++20 modules (experimental, default: OFF)."
-    OFF
-    ADVANCED
-  )
-  if(HPX_WITH_BUILD_USING_CXX_MODULES)
-    hpx_add_config_define(HPX_HAVE_BUILD_USING_CXX_MODULES)
-  endif()
+  set(HPX_WITH_CXX_MODULES_OPTION SCAN_FOR_MODULES ON)
 else()
   hpx_info("HPX will be built and used with traditional headers only.")
 endif()

cmake/HPX_AddComponent.cmake

@@ -314,8 +314,10 @@ function(add_hpx_component name)
   # module interface unit exposed from the HPX libraries
   if(HPX_WITH_CXX_MODULES)
     if((NOT CMAKE_CXX_SCAN_FOR_MODULES) AND (NOT ${name}_SCAN_FOR_MODULES))
+      hpx_debug("add_component.${name} SCAN_FOR_MODULES: OFF")
       set(${name}_SCAN_FOR_MODULES OFF)
     else()
+      hpx_debug("add_component.${name} SCAN_FOR_MODULES: ON")
       set(${name}_SCAN_FOR_MODULES ON)
     endif()
   endif()
@@ -328,8 +330,8 @@ function(add_hpx_component name)
     COMPILE_FLAGS ${${name}_COMPILE_FLAGS}
     LINK_FLAGS ${${name}_LINK_FLAGS}
     DEPENDENCIES ${${name}_DEPENDENCIES}
-    COMPONENT_DEPENDENCIES ${${name}_COMPONENT_DEPENDENCIES} ${_target_flags}
-    SCAN_FOR_MODULES ${${name}_SCAN_FOR_MODULES}
+    COMPONENT_DEPENDENCIES ${${name}_COMPONENT_DEPENDENCIES}
+    SCAN_FOR_MODULES ${${name}_SCAN_FOR_MODULES} ${_target_flags}
   )
 
 endfunction()

cmake/HPX_AddExecutable.cmake

@@ -259,8 +259,10 @@ function(add_hpx_executable name)
   # module interface unit exposed from the HPX libraries
   if(HPX_WITH_CXX_MODULES)
     if(NOT (CMAKE_CXX_SCAN_FOR_MODULES OR ${name}_SCAN_FOR_MODULES))
+      hpx_debug("add_executable.${name} SCAN_FOR_MODULES: OFF")
       set(${name}_SCAN_FOR_MODULES OFF)
     else()
+      hpx_debug("add_executable.${name} SCAN_FOR_MODULES: ON")
       set(${name}_SCAN_FOR_MODULES ON)
     endif()
   endif()

cmake/HPX_AddLibrary.cmake

@@ -314,8 +314,10 @@ function(add_hpx_library name)
   # module interface unit exposed from the HPX libraries
   if(HPX_WITH_CXX_MODULES)
     if(NOT (CMAKE_CXX_SCAN_FOR_MODULES OR ${name}_SCAN_FOR_MODULES))
+      hpx_debug("add_library.${name} SCAN_FOR_MODULES: OFF")
       set(${name}_SCAN_FOR_MODULES OFF)
     else()
+      hpx_debug("add_library.${name} SCAN_FOR_MODULES: ON")
       set(${name}_SCAN_FOR_MODULES ON)
     endif()
   endif()

cmake/HPX_SetupTarget.cmake

@@ -225,9 +225,12 @@ function(hpx_setup_target target)
 
   set_target_properties(${target} PROPERTIES POSITION_INDEPENDENT_CODE ON)
 
-  if(HPX_WITH_CXX_MODULES AND ${target}_SCAN_FOR_MODULES)
+  if(HPX_WITH_CXX_MODULES AND target_SCAN_FOR_MODULES)
+    hpx_debug("setup_target.${target} SCAN_FOR_MODULES: ON")
     hpx_configure_module_consumer(${target} hpx_core_module_if)
   else()
+    hpx_debug("setup_target.${target} SCAN_FOR_MODULES: OFF")
+
     # If modules are enabled, Clang emits DWARF v5, which requires using lld
     # instead of ld.
     if(HPX_WITH_CXX_MODULES AND (CMAKE_CXX_COMPILER_ID MATCHES "Clang"

components/component_storage/CMakeLists.txt

@@ -35,10 +35,11 @@ add_hpx_component(
   INSTALL_COMPONENT runtime
   HEADER_ROOT ${CMAKE_CURRENT_SOURCE_DIR}/include
   HEADERS ${component_storage_headers}
-  PREPEND_SOURCE_ROOT
+  PREPEND_SOURCE_ROOT ${HPX_WITH_UNITY_BUILD_OPTION}
+  ${HPX_WITH_CXX_MODULES_OPTION}
   SOURCE_ROOT ${CMAKE_CURRENT_SOURCE_DIR}/src
   SOURCES ${component_storage_sources}
-  DEPENDENCIES unordered_component ${HPX_WITH_UNITY_BUILD_OPTION}
+  DEPENDENCIES unordered_component
 )
 
 target_compile_definitions(

components/component_storage/tests/unit/CMakeLists.txt

@@ -21,7 +21,7 @@ foreach(test ${tests})
   add_hpx_executable(
     ${test}_test INTERNAL_FLAGS
     SOURCES ${sources} ${${test}_FLAGS}
-    EXCLUDE_FROM_ALL
+    EXCLUDE_FROM_ALL ${HPX_WITH_CXX_MODULES_OPTION}
     HPX_PREFIX ${HPX_BUILD_PREFIX}
     FOLDER ${folder_name}
   )

components/containers/partitioned_vector/CMakeLists.txt

@@ -49,9 +49,10 @@ add_hpx_component(
   INSTALL_COMPONENT runtime
   HEADER_ROOT "${CMAKE_CURRENT_SOURCE_DIR}/include"
   HEADERS ${partitioned_vector_headers}
-  PREPEND_SOURCE_ROOT
+  PREPEND_SOURCE_ROOT ${HPX_WITH_UNITY_BUILD_OPTION}
+  ${HPX_WITH_CXX_MODULES_OPTION}
   SOURCE_ROOT "${CMAKE_CURRENT_SOURCE_DIR}/src"
-  SOURCES ${partitioned_vector_sources} ${HPX_WITH_UNITY_BUILD_OPTION}
+  SOURCES ${partitioned_vector_sources}
 )
 
 target_compile_definitions(

components/containers/partitioned_vector/tests/regressions/CMakeLists.txt

@@ -20,7 +20,7 @@ foreach(test ${tests})
   add_hpx_executable(
     ${test}_test INTERNAL_FLAGS
     SOURCES ${sources} ${${test}_FLAGS}
-    EXCLUDE_FROM_ALL
+    EXCLUDE_FROM_ALL ${HPX_WITH_CXX_MODULES_OPTION}
     HPX_PREFIX ${HPX_BUILD_PREFIX}
     FOLDER "Tests/Regressions/Components/Containers/PartitionedVector"
   )

components/containers/partitioned_vector/tests/unit/CMakeLists.txt

@@ -53,7 +53,7 @@ foreach(test ${tests})
   add_hpx_executable(
     ${test}_test INTERNAL_FLAGS
     SOURCES ${sources} ${${test}_FLAGS}
-    EXCLUDE_FROM_ALL
+    EXCLUDE_FROM_ALL ${HPX_WITH_CXX_MODULES_OPTION}
     HPX_PREFIX ${HPX_BUILD_PREFIX}
     FOLDER ${folder_name}
   )