Merge topic 'ninja-better-order-depends'

ed45432571 cmNinjaTargetGenerator: do not order-depend on C++ module sources
0973cd6702 cmNinjaTargetGenerator: use the file set visibility API
4625170925 cmFileSet: add a query for includeable file set types
51f9d9f0a2 cmNinjaTargetGenerator: avoid traversing old outputs repeatedly

Acked-by: Kitware Robot <[email protected]>
Tested-by: buildbot <[email protected]>
Merge-request: !8902

Help/policy/CMP0154.rst

@@ -22,6 +22,12 @@ type ``HEADERS``.  With this information, :ref:`Ninja Generators` may omit
 the above-mentioned conservative dependencies and produce more efficient
 build graphs.
 
+Additionally, if the custom command's output is a member of a file set of type
+``CXX_MODULES``, it will additionally not be required to exist before
+compiling other sources in the same target.  Since these files should not be
+included at compile time directly, they may not be implicitly required to
+exist for other compilation rules.
+
 This policy provides compatibility for projects using file sets in targets
 with generated header files that have not been updated.  Such projects
 should be updated to express generated public headers in a file set.

Source/cmFileSet.cxx

@@ -80,6 +80,11 @@ bool cmFileSetVisibilityIsForInterface(cmFileSetVisibility vis)
   return false;
 }
 
+bool cmFileSetTypeCanBeIncluded(std::string const& type)
+{
+  return type == "HEADERS"_s;
+}
+
 cmFileSet::cmFileSet(cmake& cmakeInstance, std::string name, std::string type,
                      cmFileSetVisibility visibility)
   : CMakeInstance(cmakeInstance)

Source/cmFileSet.h

@@ -31,6 +31,8 @@ cmFileSetVisibility cmFileSetVisibilityFromName(cm::string_view name,
 bool cmFileSetVisibilityIsForSelf(cmFileSetVisibility vis);
 bool cmFileSetVisibilityIsForInterface(cmFileSetVisibility vis);
 
+bool cmFileSetTypeCanBeIncluded(std::string const& type);
+
 class cmFileSet
 {
 public:

Source/cmNinjaTargetGenerator.cxx

@@ -1048,21 +1048,29 @@ void cmNinjaTargetGenerator::WriteObjectBuildStatements(
       cmCustomCommandGenerator ccg(*cc, config, this->GetLocalGenerator());
       const std::vector<std::string>& ccoutputs = ccg.GetOutputs();
       const std::vector<std::string>& ccbyproducts = ccg.GetByproducts();
+      auto const nPreviousOutputs = ccouts.size();
       ccouts.insert(ccouts.end(), ccoutputs.begin(), ccoutputs.end());
       ccouts.insert(ccouts.end(), ccbyproducts.begin(), ccbyproducts.end());
       if (usePrivateGeneratedSources) {
         auto it = ccouts.begin();
+        // Skip over outputs that were already detected.
+        std::advance(it, nPreviousOutputs);
         while (it != ccouts.end()) {
           cmFileSet const* fileset =
             this->GeneratorTarget->GetFileSetForSource(
               config, this->Makefile->GetOrCreateGeneratedSource(*it));
-          if (fileset &&
-              fileset->GetVisibility() != cmFileSetVisibility::Private) {
+          bool isVisible = fileset &&
+            cmFileSetVisibilityIsForInterface(fileset->GetVisibility());
+          bool isIncludeable =
+            !fileset || cmFileSetTypeCanBeIncluded(fileset->GetType());
+          if (fileset && isVisible && isIncludeable) {
             ++it;
-          } else {
+            continue;
+          }
+          if (!fileset || isIncludeable) {
             ccouts_private.push_back(*it);
-            it = ccouts.erase(it);
           }
+          it = ccouts.erase(it);
         }
       }
     }

Tests/RunCMake/CXXModules/RunCMakeTest.cmake

@@ -133,7 +133,11 @@ function (run_cxx_module_test directory)
     ${ARGN})
   run_cmake("examples/${test_name}")
   set(RunCMake_TEST_NO_CLEAN 1)
-  run_cmake_command("examples/${test_name}-build" "${CMAKE_COMMAND}" --build . --config Debug)
+  if (RunCMake_CXXModules_TARGET)
+    run_cmake_command("examples/${test_name}-build" "${CMAKE_COMMAND}" --build . --config Debug --target "${RunCMake_CXXModules_TARGET}")
+  else ()
+    run_cmake_command("examples/${test_name}-build" "${CMAKE_COMMAND}" --build . --config Debug)
+  endif ()
   if (RunCMake_CXXModules_INSTALL)
     run_cmake_command("examples/${test_name}-install" "${CMAKE_COMMAND}" --build . --target install --config Debug)
   endif ()
@@ -142,8 +146,23 @@ function (run_cxx_module_test directory)
   endif ()
 endfunction ()
 
+function (run_cxx_module_test_target directory target)
+  set(RunCMake_CXXModules_TARGET "${target}")
+  set(RunCMake_CXXModules_NO_TEST 1)
+  run_cxx_module_test("${directory}" ${ARGN})
+endfunction ()
+
 string(REPLACE "," ";" CMake_TEST_MODULE_COMPILATION "${CMake_TEST_MODULE_COMPILATION}")
 
+if (RunCMake_GENERATOR MATCHES "Ninja")
+  if (RunCMake_GENERATOR_IS_MULTI_CONFIG)
+    set(ninja_cmp0154_target "CMakeFiles/ninja_cmp0154.dir/Debug/unrelated.cxx${CMAKE_CXX_OUTPUT_EXTENSION}")
+  else ()
+    set(ninja_cmp0154_target "CMakeFiles/ninja_cmp0154.dir/unrelated.cxx${CMAKE_CXX_OUTPUT_EXTENSION}")
+  endif ()
+  run_cxx_module_test_target(ninja-cmp0154 "${ninja_cmp0154_target}")
+endif ()
+
 # Tests which use named modules.
 if ("named" IN_LIST CMake_TEST_MODULE_COMPILATION)
   run_cxx_module_test(simple)

Tests/RunCMake/CXXModules/examples/ninja-cmp0154-build-check.cmake

@@ -0,0 +1,4 @@
+if (EXISTS "${RunCMake_TEST_BINARY_DIR}/importable.cxx")
+  list(APPEND RunCMake_TEST_FAILED
+    "The `importable.cxx` file should not be generated to compile `unrelated`'s object")
+endif ()

Tests/RunCMake/CXXModules/examples/ninja-cmp0154/CMakeLists.txt

@@ -0,0 +1,31 @@
+cmake_minimum_required(VERSION 3.24...3.28)
+project(cxx_modules_ninja_cmp0154 CXX)
+
+include("${CMAKE_SOURCE_DIR}/../cxx-modules-rules.cmake")
+
+add_custom_command(
+  OUTPUT  "${CMAKE_CURRENT_BINARY_DIR}/importable.cxx"
+  DEPENDS "${CMAKE_CURRENT_SOURCE_DIR}/importable.cxx.in"
+  COMMAND "${CMAKE_COMMAND}"
+          -E copy_if_different
+          "${CMAKE_CURRENT_SOURCE_DIR}/importable.cxx.in"
+          "${CMAKE_CURRENT_BINARY_DIR}/importable.cxx"
+  COMMENT "Copying 'importable.cxx'")
+
+add_executable(ninja_cmp0154)
+target_sources(ninja_cmp0154
+  PRIVATE
+    main.cxx
+    unrelated.cxx
+  PUBLIC
+    FILE_SET CXX_MODULES
+      BASE_DIRS
+      "${CMAKE_CURRENT_BINARY_DIR}"
+      FILES
+        "${CMAKE_CURRENT_BINARY_DIR}/importable.cxx")
+target_compile_features(ninja_cmp0154 PUBLIC cxx_std_20)
+set_property(SOURCE unrelated.cxx
+  PROPERTY
+    CXX_SCAN_FOR_MODULES 0)
+
+add_test(NAME ninja_cmp0154 COMMAND ninja_cmp0154)

Tests/RunCMake/CXXModules/examples/ninja-cmp0154/importable.cxx.in

@@ -0,0 +1,5 @@
+export module importable;
+
+export int from_import() {
+  return 0;
+}

Tests/RunCMake/CXXModules/examples/ninja-cmp0154/main.cxx

@@ -0,0 +1,8 @@
+import importable;
+
+extern int unrelated();
+
+int main(int argc, char* argv[])
+{
+  return from_import() + unrelated();
+}

Tests/RunCMake/CXXModules/examples/ninja-cmp0154/unrelated.cxx

@@ -0,0 +1,4 @@
+int unrelated()
+{
+  return 0;
+}