Add a build-script + CMake flag to enable/disable building the _Volatile module

CMakeLists.txt

@@ -712,6 +712,10 @@ option(SWIFT_ENABLE_SYNCHRONIZATION
   "Enable build of the Swift Synchronization module"
   FALSE)
 
+option(SWIFT_ENABLE_VOLATILE
+  "Enable build of the Swift Volatile module"
+  FALSE)
+
 option(SWIFT_ENABLE_DISPATCH
   "Enable use of libdispatch"
   TRUE)
@@ -1359,6 +1363,7 @@ if(SWIFT_BUILD_STDLIB OR SWIFT_BUILD_SDK_OVERLAY)
   message(STATUS "Unicode Support:                    ${SWIFT_STDLIB_ENABLE_UNICODE_DATA}")
   message(STATUS "Observation Support:                ${SWIFT_ENABLE_EXPERIMENTAL_OBSERVATION}")
   message(STATUS "Synchronization Support:            ${SWIFT_ENABLE_SYNCHRONIZATION}")
+  message(STATUS "Volatile Support:                   ${SWIFT_ENABLE_VOLATILE}")
   message(STATUS "")
 else()
   message(STATUS "Not building Swift standard library, SDK overlays, and runtime")

stdlib/cmake/modules/SwiftSource.cmake

@@ -330,6 +330,10 @@ function(_add_target_variant_swift_compile_flags
     list(APPEND result "-D" "SWIFT_ENABLE_SYNCHRONIZATION")
   endif()
 
+  if(SWIFT_ENABLE_VOLATILE)
+    list(APPEND result "-D" "SWIFT_ENABLE_VOLATILE")
+  endif()
+
   if(SWIFT_STDLIB_OS_VERSIONING)
     list(APPEND result "-D" "SWIFT_RUNTIME_OS_VERSIONING")
   endif()

stdlib/public/CMakeLists.txt

@@ -282,7 +282,9 @@ if(SWIFT_BUILD_STDLIB AND NOT SWIFT_STDLIB_BUILD_ONLY_CORE_MODULES)
     add_subdirectory(Synchronization)
   endif()
 
-  add_subdirectory(Volatile)
+  if(SWIFT_ENABLE_VOLATILE)
+    add_subdirectory(Volatile)
+  endif()
 endif()
 
 if(SWIFT_BUILD_REMOTE_MIRROR)

test/CMakeLists.txt

@@ -215,6 +215,7 @@ normalize_boolean_spelling(SWIFT_STDLIB_ENABLE_OBJC_INTEROP)
 normalize_boolean_spelling(SWIFT_ENABLE_BACKTRACING)
 normalize_boolean_spelling(SWIFT_BUILD_SWIFT_SYNTAX)
 normalize_boolean_spelling(SWIFT_ENABLE_SYNCHRONIZATION)
+normalize_boolean_spelling(SWIFT_ENABLE_VOLATILE)
 normalize_boolean_spelling(SWIFT_BUILD_REMOTE_MIRROR)
 is_build_type_optimized("${SWIFT_STDLIB_BUILD_TYPE}" SWIFT_OPTIMIZED)
 
@@ -433,6 +434,10 @@ foreach(SDK ${SWIFT_SDKS})
           list(APPEND LIT_ARGS "--param" "synchronization")
         endif()
 
+        if(SWIFT_ENABLE_VOLATILE)
+          list(APPEND LIT_ARGS "--param" "volatile")
+        endif()
+
         if(SWIFT_BUILD_REMOTE_MIRROR)
           list(APPEND LIT_ARGS "--param" "remote_mirror")
         endif()

test/lit.site.cfg.in

@@ -157,6 +157,8 @@ if "@SWIFT_STDLIB_ENABLE_DEBUG_PRECONDITIONS_IN_RELEASE@" == "TRUE":
     config.available_features.add('swift_stdlib_debug_preconditions_in_release')
 if "@SWIFT_ENABLE_SYNCHRONIZATION@" == "TRUE":
     config.available_features.add('synchronization')
+if "@SWIFT_ENABLE_VOLATILE@" == "TRUE":
+    config.available_features.add('volatile')
 if "@SWIFT_SHOULD_BUILD_EMBEDDED_STDLIB@" == "TRUE":
     config.available_features.add('embedded_stdlib')
 

utils/build.ps1

@@ -1345,6 +1345,7 @@ function Build-Compilers() {
         SWIFT_ENABLE_EXPERIMENTAL_OBSERVATION = "YES";
         SWIFT_ENABLE_EXPERIMENTAL_STRING_PROCESSING = "YES";
         SWIFT_ENABLE_SYNCHRONIZATION = "YES";
+        SWIFT_ENABLE_VOLATILE = "YES";
         SWIFT_PATH_TO_LIBDISPATCH_SOURCE = "$SourceCache\swift-corelibs-libdispatch";
         SWIFT_PATH_TO_SWIFT_SYNTAX_SOURCE = "$SourceCache\swift-syntax";
         SWIFT_PATH_TO_STRING_PROCESSING_SOURCE = "$SourceCache\swift-experimental-string-processing";
@@ -1594,6 +1595,7 @@ function Build-Runtime([Platform]$Platform, $Arch) {
         SWIFT_ENABLE_EXPERIMENTAL_STRING_PROCESSING = "YES";
         # FIXME: re-enable after https://github.com/apple/swift/issues/74186 is fixed.
         SWIFT_ENABLE_SYNCHRONIZATION = if (($Platform -eq "Android") -and ($Arch -eq $AndroidARMv7)) { "NO" } else { "YES" };
+        SWIFT_ENABLE_VOLATILE = "YES";
         SWIFT_NATIVE_SWIFT_TOOLS_PATH = (Join-Path -Path $CompilersBinaryCache -ChildPath "bin");
         SWIFT_PATH_TO_LIBDISPATCH_SOURCE = "$SourceCache\swift-corelibs-libdispatch";
         SWIFT_PATH_TO_STRING_PROCESSING_SOURCE = "$SourceCache\swift-experimental-string-processing";

utils/build_swift/build_swift/driver_arguments.py

@@ -1465,6 +1465,10 @@ def create_argument_parser():
            default=True,
            help='Enable Swift Synchronization.')
 
+    option('--enable-volatile', toggle_true,
+           default=True,
+           help='Enable Volatile module.')
+
     option('--enable-experimental-parser-validation', toggle_true,
            default=False,
            help='Enable experimental Swift Parser validation by default.')

utils/build_swift/tests/expected_options.py

@@ -181,6 +181,7 @@ EXPECTED_DEFAULTS = {
     'enable_experimental_parser_validation': False,
     'swift_enable_backtracing': True,
     'enable_synchronization': True,
+    'enable_volatile': True,
     'enable_lsan': False,
     'enable_sanitize_coverage': False,
     'disable_guaranteed_normal_arguments': False,
@@ -622,6 +623,7 @@ EXPECTED_OPTIONS = [
     EnableOption('--export-compile-commands'),
     EnableOption('--swift-enable-backtracing'),
     EnableOption('--enable-synchronization'),
+    EnableOption('--enable-volatile'),
     EnableOption('--foundation', dest='build_foundation'),
     EnableOption('--host-test'),
     EnableOption('--only-executable-test'),

utils/swift-api-dump.py

@@ -108,6 +108,8 @@ def create_parser():
                         help='Enable experimental observation.')
     parser.add_argument('--enable-synchronization', action='store_true',
                         help='Enable Synchronization.')
+    parser.add_argument('--enable-volatile', action='store_true',
+                        help='Enable Volatile.')
     parser.add_argument('-swift-version', metavar='N',
                         help='the Swift version to use')
     parser.add_argument('-show-overlay', action='store_true',

utils/swift_build_support/swift_build_support/products/swift.py

@@ -72,6 +72,9 @@ class Swift(product.Product):
         # Add synchronization flag.
         self.cmake_options.extend(self._enable_synchronization)
 
+        # Add volatile flag.
+        self.cmake_options.extend(self._enable_volatile)
+
         # Add static vprintf flag
         self.cmake_options.extend(self._enable_stdlib_static_vprintf)
 
@@ -219,6 +222,11 @@ updated without updating swift.py?")
         return [('SWIFT_ENABLE_SYNCHRONIZATION:BOOL',
                  self.args.enable_synchronization)]
 
+    @property
+    def _enable_volatile(self):
+        return [('SWIFT_ENABLE_VOLATILE:BOOL',
+                 self.args.enable_volatile)]
+
     @property
     def _enable_stdlib_static_vprintf(self):
         return [('SWIFT_STDLIB_STATIC_PRINT',

utils/swift_build_support/swift_build_support/products/wasmstdlib.py

@@ -110,6 +110,7 @@ class WasmStdlib(cmake_product.CMakeProduct):
                                                'swift-experimental-string-processing'))
         self.cmake_options.define('SWIFT_ENABLE_EXPERIMENTAL_CXX_INTEROP:BOOL', 'TRUE')
         self.cmake_options.define('SWIFT_ENABLE_SYNCHRONIZATION:BOOL', 'TRUE')
+        self.cmake_options.define('SWIFT_ENABLE_VOLATILE:BOOL', 'TRUE')
         self.cmake_options.define('SWIFT_ENABLE_EXPERIMENTAL_OBSERVATION:BOOL', 'TRUE')
 
         self.add_extra_cmake_options()

utils/swift_build_support/tests/products/test_swift.py

@@ -63,6 +63,7 @@ class SwiftTestCase(unittest.TestCase):
             enable_experimental_parser_validation=False,
             swift_enable_backtracing=False,
             enable_synchronization=False,
+            enable_volatile=False,
             build_early_swiftsyntax=False,
             build_swift_stdlib_static_print=False,
             build_swift_stdlib_unicode_data=True,
@@ -109,6 +110,7 @@ class SwiftTestCase(unittest.TestCase):
             '-DSWIFT_ENABLE_EXPERIMENTAL_PARSER_VALIDATION:BOOL=FALSE',
             '-DSWIFT_ENABLE_BACKTRACING:BOOL=FALSE',
             '-DSWIFT_ENABLE_SYNCHRONIZATION:BOOL=FALSE',
+            '-DSWIFT_ENABLE_VOLATILE:BOOL=FALSE',
             '-DSWIFT_STDLIB_STATIC_PRINT=FALSE',
             '-DSWIFT_FREESTANDING_IS_DARWIN:BOOL=FALSE',
             '-DSWIFT_STDLIB_BUILD_PRIVATE:BOOL=TRUE',
@@ -140,6 +142,7 @@ class SwiftTestCase(unittest.TestCase):
             '-DSWIFT_ENABLE_EXPERIMENTAL_PARSER_VALIDATION:BOOL=FALSE',
             '-DSWIFT_ENABLE_BACKTRACING:BOOL=FALSE',
             '-DSWIFT_ENABLE_SYNCHRONIZATION:BOOL=FALSE',
+            '-DSWIFT_ENABLE_VOLATILE:BOOL=FALSE',
             '-DSWIFT_STDLIB_STATIC_PRINT=FALSE',
             '-DSWIFT_FREESTANDING_IS_DARWIN:BOOL=FALSE',
             '-DSWIFT_STDLIB_BUILD_PRIVATE:BOOL=TRUE',
@@ -461,6 +464,19 @@ class SwiftTestCase(unittest.TestCase):
             [x for x in swift.cmake_options
              if 'DSWIFT_ENABLE_SYNCHRONIZATION' in x])
 
+    def test_volatile_flags(self):
+        self.args.enable_volatile = True
+        swift = Swift(
+            args=self.args,
+            toolchain=self.toolchain,
+            source_dir='/path/to/src',
+            build_dir='/path/to/build')
+        self.assertEqual(
+            ['-DSWIFT_ENABLE_VOLATILE:BOOL='
+             'TRUE'],
+            [x for x in swift.cmake_options
+             if 'DSWIFT_ENABLE_VOLATILE' in x])
+
     def test_freestanding_is_darwin_flags(self):
         self.args.swift_freestanding_is_darwin = True
         swift = Swift(