[SR-1738] Allow *only* static libraries to be built

This splits the `--build-swift-stdlib` and `--build-swift-sdk-overlay`
arguments into `dynamic` and `static` variants, which makes the
following build command possible:

```
utils/build-script -- \
  --build-swift-dynamic-stdlib=0 --build-swift-dynamic-sdk-overlay=0 \
  --build-swift-static-stdlib=1 --build-swift-static-sdk-overlay=0
```

This command produces *only* static libraries for the stdlib, and no
SDK overlay libraries at all. Many other finely-grained build options
are now possible.

Author: modocache

CMakeLists.txt

@@ -48,18 +48,40 @@ option(SWIFT_BUILD_TOOLS
     "Build the Swift compiler and other tools"
     TRUE)
 
-option(SWIFT_BUILD_STDLIB
-    "Build the Swift standard library (independent of the SDK headers)"
+option(SWIFT_BUILD_DYNAMIC_STDLIB
+    "Build dynamic variants of the Swift standard library"
     TRUE)
 
-option(SWIFT_BUILD_SDK_OVERLAY
-    "Build Swift SDK overlay"
+option(SWIFT_BUILD_STATIC_STDLIB
+    "Build static variants of the Swift standard library"
+    FALSE)
+
+option(SWIFT_BUILD_DYNAMIC_SDK_OVERLAY
+    "Build dynamic variants of the Swift SDK overlay"
     TRUE)
 
-option(SWIFT_BUILD_STATIC_STDLIB
-    "Build static variants of the Swift standard library and SDK overlay"
+option(SWIFT_BUILD_STATIC_SDK_OVERLAY
+    "Build static variants of the Swift SDK overlay"
     FALSE)
 
+# In many cases, the CMake build system needs to determine whether to include
+# a directory, or perform other actions, based on whether the stdlib or SDK is
+# being built at all -- statically or dynamically. Please note that these
+# flags are not related to the deprecated build-script-impl arguments
+# 'build-swift-stdlib' and 'build-swift-sdk-overlay'. These are not flags that
+# the build script should be able to set.
+if(SWIFT_BUILD_DYNAMIC_STDLIB OR SWIFT_BUILD_STATIC_STDLIB)
+  set(SWIFT_BUILD_STDLIB TRUE)
+else()
+  set(SWIFT_BUILD_STDLIB FALSE)
+endif()
+
+if(SWIFT_BUILD_DYNAMIC_SDK_OVERLAY OR SWIFT_BUILD_STATIC_SDK_OVERLAY)
+  set(SWIFT_BUILD_SDK_OVERLAY TRUE)
+else()
+  set(SWIFT_BUILD_SDK_OVERLAY FALSE)
+endif()
+
 option(SWIFT_BUILD_PERF_TESTSUITE
     "Create targets for swift performance benchmarks."
     FALSE)
@@ -798,7 +820,7 @@ endif()
 add_subdirectory(utils)
 add_subdirectory(stdlib)
 
-if(SWIFT_BUILD_STDLIB AND SWIFT_INCLUDE_TESTS)
+if(SWIFT_BUILD_DYNAMIC_STDLIB AND SWIFT_INCLUDE_TESTS)
   add_subdirectory(tools/swift-reflection-test)
 endif()
 

cmake/modules/AddSwift.cmake

@@ -557,10 +557,15 @@ function(_add_swift_library_single target name)
     set(libkind MODULE)
   elseif(SWIFTLIB_SINGLE_OBJECT_LIBRARY)
     set(libkind OBJECT)
+  # If both SHARED and STATIC are specified, we add the SHARED library first.
+  # The STATIC library is handled further below.
   elseif(SWIFTLIB_SINGLE_SHARED)
     set(libkind SHARED)
+  elseif(SWIFTLIB_SINGLE_STATIC)
+    set(libkind STATIC)
   else()
-    set(libkind)
+    message(FATAL_ERROR
+        "Either SHARED, STATIC, or OBJECT_LIBRARY must be specified")
   endif()
 
   handle_gyb_sources(
@@ -721,7 +726,6 @@ function(_add_swift_library_single target name)
   # Configure the static library target.
   # Set compile and link flags for the non-static target.
   # Do these LAST.
-
   set(target_static)
   if(SWIFTLIB_SINGLE_IS_STDLIB AND SWIFTLIB_SINGLE_STATIC)
     set(target_static "${target}-static")

stdlib/CMakeLists.txt

@@ -10,8 +10,10 @@ else()
   set(CMAKE_C_COMPILER_ARG1 "")
 endif()
 
-# FIXME: Make it possible to build *only* static libraries for the stdlib.
-set(SWIFT_STDLIB_LIBRARY_BUILD_TYPES SHARED)
+set(SWIFT_STDLIB_LIBRARY_BUILD_TYPES)
+if(SWIFT_BUILD_DYNAMIC_STDLIB)
+  list(APPEND SWIFT_STDLIB_LIBRARY_BUILD_TYPES SHARED)
+endif()
 if(SWIFT_BUILD_STATIC_STDLIB)
   list(APPEND SWIFT_STDLIB_LIBRARY_BUILD_TYPES STATIC)
 endif()

stdlib/public/SDK/CMakeLists.txt

@@ -1,8 +1,10 @@
 # All libraries in this directory tree are overlays that depend on Darwin SDK.
 
-# FIXME: Make it possible to build *only* static libraries for the SDK overlays.
-set(SWIFT_SDK_OVERLAY_LIBRARY_BUILD_TYPES SHARED)
-if(SWIFT_BUILD_STATIC_STDLIB)
+set(SWIFT_SDK_OVERLAY_LIBRARY_BUILD_TYPES)
+if(SWIFT_BUILD_DYNAMIC_SDK_OVERLAY)
+  list(APPEND SWIFT_SDK_OVERLAY_LIBRARY_BUILD_TYPES SHARED)
+endif()
+if(SWIFT_BUILD_STATIC_SDK_OVERLAY)
   list(APPEND SWIFT_SDK_OVERLAY_LIBRARY_BUILD_TYPES STATIC)
 endif()
 

stdlib/public/SwiftRemoteMirror/CMakeLists.txt

@@ -1,6 +1,8 @@
 # libswiftRemoteMirror.dylib should not have runtime dependencies; it's
 # always built as a shared library.
-add_swift_library(swiftRemoteMirror SHARED TARGET_LIBRARY DONT_EMBED_BITCODE
-    SwiftRemoteMirror.cpp
-    LINK_LIBRARIES swiftReflection
-    INSTALL_IN_COMPONENT stdlib)
+if(SWIFT_BUILD_DYNAMIC_STDLIB)
+  add_swift_library(swiftRemoteMirror SHARED TARGET_LIBRARY DONT_EMBED_BITCODE
+      SwiftRemoteMirror.cpp
+      LINK_LIBRARIES swiftReflection
+      INSTALL_IN_COMPONENT stdlib)
+endif()

utils/build-script

@@ -364,6 +364,27 @@ class BuildScriptInvocation(object):
             args.skip_test_tvos = True
             args.skip_test_watchos = True
 
+        # --build-swift-stdlib and --build-swift-sdk-overlay are deprecated
+        # aliases for --build-swift-{dynamic,static}-stdlib and
+        # --build-swift-{dynamic,static}-sdk-overlay. The deprecated options
+        # are None by default, but if specified they take precedence over the
+        # new, more granular options.
+        if args.build_swift_stdlib is not None:
+            if args.build_swift_stdlib:
+                args.build_swift_dynamic_stdlib = True
+                args.build_swift_static_stdlib = False
+            else:
+                args.build_swift_dynamic_stdlib = False
+                args.build_swift_static_stdlib = False
+
+        if args.build_swift_sdk_overlay is not None:
+            if args.build_swift_sdk_overlay:
+                args.build_swift_dynamic_sdk_overlay = True
+                args.build_swift_static_sdk_overlay = False
+            else:
+                args.build_swift_dynamic_sdk_overlay = False
+                args.build_swift_static_sdk_overlay = False
+
         # --skip-test-ios is merely a shorthand for host and simulator tests.
         if args.skip_test_ios:
             args.skip_test_ios_host = True
@@ -636,8 +657,16 @@ class BuildScriptInvocation(object):
             impl_args += ["--skip-build-libdispatch"]
         if not args.build_swiftpm:
             impl_args += ["--skip-build-swiftpm"]
+        if args.build_swift_dynamic_stdlib:
+            impl_args += ["--build-swift-dynamic-stdlib"]
+        if args.build_swift_static_stdlib:
+            impl_args += ["--build-swift-static-stdlib"]
         if args.build_swift_stdlib_unittest_extra:
             impl_args += ["--build-swift-stdlib-unittest-extra"]
+        if args.build_swift_dynamic_sdk_overlay:
+            impl_args += ["--build-swift-dynamic-sdk-overlay"]
+        if args.build_swift_static_sdk_overlay:
+            impl_args += ["--build-swift-static-sdk-overlay"]
 
         if args.skip_build_linux:
             impl_args += ["--skip-build-linux"]
@@ -1507,13 +1536,45 @@ details of the setups of other systems or automated environments.""")
         help="Use the host compiler, not the self-built one to compile the "
              "Swift runtime",
         action=arguments.action.optional_bool)
-    parser.add_argument(
-        "--build-swift-stdlib-unittest-extra",
-        help="Build optional StdlibUnittest components",
-        action=arguments.action.optional_bool)
 
     run_build_group = parser.add_argument_group(
         title="Run build")
+    run_build_group.add_argument(
+        "--build-swift-stdlib",
+        help="a deprecated alias for '--build-swift-dynamic-stdlib=1 "
+             "--build-swift-static-stdlib=0'. When specified, this takes "
+             "precedence over those options",
+        action=arguments.action.optional_bool,
+        default=None)
+    run_build_group.add_argument(
+        "--build-swift-dynamic-stdlib",
+        help="build dynamic variants of the Swift standard library",
+        action=arguments.action.optional_bool,
+        default=True)
+    run_build_group.add_argument(
+        "--build-swift-static-stdlib",
+        help="build static variants of the Swift standard library",
+        action=arguments.action.optional_bool)
+    run_build_group.add_argument(
+        "--build-swift-sdk-overlay",
+        help="a deprecated alias for '--build-swift-dynamic-sdk-overlay=1 "
+             "--build-swift-static-sdk-overlay=0'. When specified, this takes "
+             "precedence over those options",
+        action=arguments.action.optional_bool,
+        default=None)
+    run_build_group.add_argument(
+        "--build-swift-dynamic-sdk-overlay",
+        help="build dynamic variants of the Swift SDK overlay",
+        action=arguments.action.optional_bool,
+        default=True)
+    run_build_group.add_argument(
+        "--build-swift-static-sdk-overlay",
+        help="build static variants of the Swift SDK overlay",
+        action=arguments.action.optional_bool)
+    run_build_group.add_argument(
+        "--build-swift-stdlib-unittest-extra",
+        help="Build optional StdlibUnittest components",
+        action=arguments.action.optional_bool)
     run_build_group.add_argument(
         "-S", "--skip-build",
         help="generate build directory only without building",

utils/build-script-impl

@@ -154,10 +154,11 @@ KNOWN_SETTINGS=(
     enable-llvm-assertions      "1"              "set to enable llvm assertions"
     build-llvm                  "1"              "set to 1 to build LLVM and Clang"
     build-swift-tools           "1"              "set to 1 to build Swift host tools"
-    build-swift-stdlib          "1"              "set to 1 to build the Swift standard library"
+    build-swift-dynamic-stdlib  ""               "set to 1 to build dynamic variants of the Swift standard library"
+    build-swift-static-stdlib   ""               "set to 1 to build static variants of the Swift standard library"
     build-swift-stdlib-unittest-extra "0"        "set to 1 to build optional StdlibUnittest components"
-    build-swift-sdk-overlay     "1"              "set to 1 to build the Swift SDK overlay"
-    build-swift-static-stdlib   "0"              "set to 1 to build static versions of the Swift standard library and SDK overlay"
+    build-swift-dynamic-sdk-overlay   ""         "set to 1 to build dynamic variants of the Swift SDK overlay"
+    build-swift-static-sdk-overlay    ""         "set to 1 to build static variants of the Swift SDK overlay"
     build-swift-examples        "1"              "set to 1 to build examples"
     build-serialized-stdlib-unittest "0"         "set to 1 to build the StdlibUnittest module with -sil-serialize-all"
     build-sil-debugging-stdlib  "0"              "set to 1 to build the Swift standard library with -gsil to enable debugging and profiling on SIL level"
@@ -1871,12 +1872,13 @@ for host in "${ALL_HOSTS[@]}"; do
                     -DSWIFT_NATIVE_CLANG_TOOLS_PATH:STRING="${native_clang_tools_path}"
                     -DSWIFT_NATIVE_SWIFT_TOOLS_PATH:STRING="${native_swift_tools_path}"
                     -DSWIFT_BUILD_TOOLS:BOOL=$(true_false "${BUILD_SWIFT_TOOLS}")
-                    -DSWIFT_BUILD_STDLIB:BOOL=$(true_false "${BUILD_SWIFT_STDLIB}")
                     -DSWIFT_SERIALIZE_STDLIB_UNITTEST:BOOL=$(true_false "${BUILD_SERIALIZED_STDLIB_UNITTEST}")
                     -DSWIFT_STDLIB_SIL_DEBUGGING:BOOL=$(true_false "${BUILD_SIL_DEBUGGING_STDLIB}")
                     -DSWIFT_CHECK_INCREMENTAL_COMPILATION:BOOL=$(true_false "${CHECK_INCREMENTAL_COMPILATION}")
-                    -DSWIFT_BUILD_SDK_OVERLAY:BOOL=$(true_false "${BUILD_SWIFT_SDK_OVERLAY}")
+                    -DSWIFT_BUILD_DYNAMIC_STDLIB:BOOL=$(true_false "${BUILD_SWIFT_DYNAMIC_STDLIB}")
                     -DSWIFT_BUILD_STATIC_STDLIB:BOOL=$(true_false "${BUILD_SWIFT_STATIC_STDLIB}")
+                    -DSWIFT_BUILD_DYNAMIC_SDK_OVERLAY:BOOL=$(true_false "${BUILD_SWIFT_DYNAMIC_SDK_OVERLAY}")
+                    -DSWIFT_BUILD_STATIC_SDK_OVERLAY:BOOL=$(true_false "${BUILD_SWIFT_STATIC_SDK_OVERLAY}")
                     -DSWIFT_BUILD_PERF_TESTSUITE:BOOL=$(true_false "${build_perf_testsuite_this_time}")
                     -DSWIFT_BUILD_EXAMPLES:BOOL=$(true_false "${BUILD_SWIFT_EXAMPLES}")
                     -DSWIFT_INCLUDE_TESTS:BOOL=$(true_false "${build_tests_this_time}")