[stdlib] Inject WinSDK module map using VFS

docs/WindowsBuild.md

@@ -98,17 +98,15 @@ alternatively, see the ICU project for details on building ICU from source.
 
 ## One-time Setup (re-run on Visual Studio upgrades)
 
-Set up the `ucrt`, `visualc`, and `WinSDK` modules by:
+Set up the `ucrt` and `visualc` modules by:
 
 - copying `ucrt.modulemap` located at `swift/stdlib/public/Platform/ucrt.modulemap` into
   `${UniversalCRTSdkDir}/Include/${UCRTVersion}/ucrt` as `module.modulemap`
 - copying `vcruntime.modulemap` located at `swift/stdlib/public/Platform/vcruntime.modulemap` into `${VCToolsInstallDir}/include` as `module.modulemap`
-- copying `winsdk.modulemap` located at `swift/stdlib/public/Platform/winsdk.modulemap` into `${UniversalCRTSdkDir}/Include/${UCRTVersion}/um`
 - and setup the `vcruntime.apinotes` located at `swift/stdlib/public/Platform/vcruntime.apinotes` into `${VCToolsInstallDir}/include` as `vcruntime.apinotes`
 
 ```cmd
 mklink "%UniversalCRTSdkDir%\Include\%UCRTVersion%\ucrt\module.modulemap" S:\swift\stdlib\public\Platform\ucrt.modulemap
-mklink "%UniversalCRTSdkDir%\Include\%UCRTVersion%\um\module.modulemap" S:\swift\stdlib\public\Platform\winsdk.modulemap
 mklink "%VCToolsInstallDir%\include\module.modulemap" S:\swift\stdlib\public\Platform\vcruntime.modulemap
 mklink "%VCToolsInstallDir%\include\vcruntime.apinotes" S:\swift\stdlib\public\Platform\vcruntime.apinotes
 ```

include/swift/AST/DiagnosticsClangImporter.def

@@ -121,6 +121,9 @@ ERROR(module_map_not_found, none, "module map file '%0' not found", (StringRef))
 WARNING(glibc_not_found, none,
         "glibc not found for '%0'; C stdlib may be unavailable",
         (StringRef))
+WARNING(windows_sdk_not_found, none,
+        "Windows SDK not found for '%0'; Platform functionalities may be unavailable",
+        (StringRef))
 WARNING(libstdcxx_not_found, none,
         "libstdc++ not found for '%0'; C++ stdlib may be unavailable",
         (StringRef))

lib/ClangImporter/ClangIncludePaths.cpp

@@ -86,6 +86,11 @@ getGlibcModuleMapPath(SearchPathOptions &Opts, const llvm::Triple &triple) {
   return getActualModuleMapPath("glibc.modulemap", Opts, triple);
 }
 
+static Optional<Path>
+getWinSDKModuleMapPath(SearchPathOptions &Opts, const llvm::Triple &triple) {
+  return getActualModuleMapPath("WinSDK.modulemap", Opts, triple);
+}
+
 static Optional<Path>
 getLibStdCxxModuleMapPath(SearchPathOptions &opts, const llvm::Triple &triple) {
   return getActualModuleMapPath("libstdcxx.modulemap", opts, triple);
@@ -226,6 +231,45 @@ getGlibcFileMapping(ASTContext &ctx) {
   };
 }
 
+static SmallVector<std::pair<std::string, std::string>, 2>
+getWinSDKFileMapping(ASTContext &ctx) {
+  const llvm::Triple &triple = ctx.LangOpts.Target;
+
+  // Extract Windows SDK path from Clang driver.
+  auto clangDriver = createClangDriver(ctx);
+  auto clangDriverArgs = createClangArgs(ctx, clangDriver);
+
+  llvm::opt::ArgStringList includeArgStrings;
+  const auto &clangToolchain =
+      clangDriver.getToolChain(clangDriverArgs, triple);
+  clangToolchain.AddClangSystemIncludeArgs(clangDriverArgs, includeArgStrings);
+  auto parsedIncludeArgs = parseClangDriverArgs(clangDriver, includeArgStrings);
+
+  // Find the include path that contains Windows.h header, which should be
+  // located under %UniversalCRTSdkDir%\Include\%UCRTVersion%\um.
+  Path winSDKDir;
+  if (auto dir = findFirstIncludeDir(parsedIncludeArgs, {"Windows.h"})) {
+    winSDKDir = dir.value();
+  } else {
+    ctx.Diags.diagnose(SourceLoc(), diag::windows_sdk_not_found, triple.str());
+    return {};
+  }
+
+  Path actualModuleMapPath;
+  if (auto path = getWinSDKModuleMapPath(ctx.SearchPathOpts, triple))
+    actualModuleMapPath = path.value();
+  else
+    // FIXME: Emit a warning of some kind.
+    return {};
+
+  Path injectedModuleMapPath(winSDKDir);
+  llvm::sys::path::append(injectedModuleMapPath, "module.modulemap");
+
+  return {
+    {std::string(injectedModuleMapPath), std::string(actualModuleMapPath)},
+  };
+}
+
 static SmallVector<std::pair<std::string, std::string>, 2>
 getLibStdCxxFileMapping(ASTContext &ctx) {
   assert(ctx.LangOpts.EnableCXXInterop &&

stdlib/public/Windows/CMakeLists.txt

@@ -1,8 +1,80 @@
+set(winsdk_modulemap_target_list)
+foreach(arch ${SWIFT_SDK_WINDOWS_ARCHITECTURES})
+set(arch_suffix "${SWIFT_SDK_WINDOWS_LIB_SUBDIR}-${arch}")
+set(arch_subdir "${SWIFT_SDK_WINDOWS_LIB_SUBDIR}/${arch}")
+
+set(module_dir "${SWIFTLIB_DIR}/${arch_subdir}")
+set(module_dir_static "${SWIFTSTATICLIB_DIR}/${arch_subdir}")
+
+set(winsdk_modulemap "winsdk.modulemap")
+set(winsdk_modulemap_out "${module_dir}/WinSDK.modulemap")
+set(winsdk_modulemap_out_static "${module_dir_static}/WinSDK.modulemap")
+
+add_custom_command_target(
+    copy_winsdk_modulemap
+    COMMAND
+    "${CMAKE_COMMAND}" "-E" "make_directory" ${module_dir}
+    COMMAND
+    "${CMAKE_COMMAND}" "-E" "copy_if_different" "${CMAKE_CURRENT_SOURCE_DIR}/${winsdk_modulemap}" "${winsdk_modulemap_out}"
+    OUTPUT ${winsdk_modulemap_out}
+    DEPENDS ${winsdk_modulemap}
+    COMMENT "Copying WinSDK modulemap to resources")
+list(APPEND winsdk_modulemap_target_list ${copy_winsdk_modulemap})
+add_dependencies(swift-stdlib-${arch_suffix} ${copy_winsdk_modulemap})
+
+if(SWIFT_BUILD_STATIC_STDLIB)
+    add_custom_command_target(
+        copy_winsdk_modulemap_static
+        COMMAND
+        "${CMAKE_COMMAND}" "-E" "make_directory" ${module_dir_static}
+        COMMAND
+        "${CMAKE_COMMAND}" "-E" "copy_if_different"
+        "${winsdk_modulemap_out}" "${winsdk_modulemap_out_static}"
+        OUTPUT ${winsdk_modulemap_out_static}
+        DEPENDS ${copy_winsdk_modulemap}
+        COMMENT "Copying WinSDK modulemap to static resources")
+    list(APPEND winsdk_modulemap_target_list ${copy_winsdk_modulemap_static})
+    add_dependencies(swift-stdlib-${arch_suffix} ${copy_winsdk_modulemap_static})
+endif()
+
+swift_install_in_component(FILES "${winsdk_modulemap_out}"
+    DESTINATION "lib/swift/${arch_subdir}"
+    COMPONENT sdk-overlay)
+
+if(SWIFT_BUILD_STATIC_STDLIB)
+    swift_install_in_component(FILES "${winsdk_modulemap_out_static}"
+        DESTINATION "lib/swift_static/${arch_subdir}"
+        COMPONENT sdk-overlay)
+endif()
+
+if(${BOOTSTRAPPING_MODE} MATCHES "BOOTSTRAPPING.*")
+    foreach(bootstrapping "0" "1")
+    get_bootstrapping_path(bootstrapping_dir ${module_dir} ${bootstrapping})
+    set(winsdk_modulemap_out_bootstrapping "${bootstrapping_dir}/WinSDK.modulemap")
+
+    add_custom_command_target(unused_var
+        COMMAND
+        "${CMAKE_COMMAND}" "-E" "make_directory" "${bootstrapping_dir}"
+        COMMAND
+        "${CMAKE_COMMAND}" "-E" "copy_if_different"
+        "${CMAKE_CURRENT_SOURCE_DIR}/${winsdk_modulemap}" "${winsdk_modulemap_out_bootstrapping}"
+
+        CUSTOM_TARGET_NAME "copy-winsdk-modulemap-bootstrapping${bootstrapping}"
+        OUTPUT "${winsdk_modulemap_out_bootstrapping}"
+        DEPENDS ${winsdk_modulemap}
+        COMMENT "Copying WinSDK modulemap to resources for bootstrapping${bootstrapping}")
+    endforeach()
+endif()
+endforeach()
+add_custom_target(winsdk-modulemap DEPENDS ${winsdk_modulemap_target_list})
+set_property(TARGET winsdk-modulemap PROPERTY FOLDER "Miscellaneous")
+add_dependencies(sdk-overlay winsdk-modulemap)
+
 add_swift_target_library(swiftWinSDK ${SWIFT_STDLIB_LIBRARY_BUILD_TYPES} IS_SDK_OVERLAY
     WinSDK.swift
 
     SWIFT_COMPILE_FLAGS ${SWIFT_RUNTIME_SWIFT_COMPILE_FLAGS} ${SWIFT_STANDARD_LIBRARY_SWIFT_FLAGS}
     LINK_FLAGS "${SWIFT_RUNTIME_SWIFT_LINK_FLAGS}"
     TARGET_SDKS WINDOWS
-    INSTALL_IN_COMPONENT sdk-overlay)
-
+    INSTALL_IN_COMPONENT sdk-overlay
+    DEPENDS winsdk-modulemap)

utils/build-windows-toolchain.bat

@@ -180,7 +180,6 @@ cmake --build "%BuildRoot%\curl" --target install || (exit /b)
 
 :: Prepare system modules
 copy /y "%SourceRoot%\swift\stdlib\public\Platform\ucrt.modulemap" "%UniversalCRTSdkDir%\Include\%UCRTVersion%\ucrt\module.modulemap" || (exit /b)
-copy /y "%SourceRoot%\swift\stdlib\public\Platform\winsdk.modulemap" "%UniversalCRTSdkDir%\Include\%UCRTVersion%\um\module.modulemap" || (exit /b)
 copy /y "%SourceRoot%\swift\stdlib\public\Platform\vcruntime.modulemap" "%VCToolsInstallDir%\include\module.modulemap" || (exit /b)
 copy /y "%SourceRoot%\swift\stdlib\public\Platform\vcruntime.apinotes" "%VCToolsInstallDir%\include\vcruntime.apinotes" || (exit /b)
 

utils/build-windows.bat

@@ -168,7 +168,6 @@ endlocal
 setlocal enableextensions enabledelayedexpansion
 
 copy /y "%source_root%\swift\stdlib\public\Platform\ucrt.modulemap" "%UniversalCRTSdkDir%\Include\%UCRTVersion%\ucrt\module.modulemap" %exitOnError%
-copy /y "%source_root%\swift\stdlib\public\Platform\winsdk.modulemap" "%UniversalCRTSdkDir%\Include\%UCRTVersion%\um\module.modulemap" %exitOnError%
 copy /y "%source_root%\swift\stdlib\public\Platform\vcruntime.modulemap" "%VCToolsInstallDir%\include\module.modulemap" %exitOnError%
 copy /y "%source_root%\swift\stdlib\public\Platform\vcruntime.apinotes" "%VCToolsInstallDir%\include\vcruntime.apinotes" %exitOnError%