Make the _Concurrency library depend on _Builtin_float

rdar://163386438

Author: DougGregor

stdlib/public/Concurrency/CMakeLists.txt

@@ -219,6 +219,14 @@ else()
   set(osx_deployment_target "${SWIFT_DARWIN_DEPLOYMENT_VERSION_OSX}")
 endif()
 
+set(SWIFT_CONCURRENCY_DEPENDENCIES)
+if((SWIFT_BUILD_CLANG_OVERLAYS
+    OR SWIFT_BUILD_TEST_SUPPORT_MODULES)
+   AND (NOT DEFINED SWIFT_BUILD_CLANG_OVERLAYS_SKIP_BUILTIN_FLOAT
+        OR NOT SWIFT_BUILD_CLANG_OVERLAYS_SKIP_BUILTIN_FLOAT))
+  set(SWIFT_CONCURRENCY_DEPENDENCIES _Builtin_float)
+endif()
+
 add_swift_target_library(swift_Concurrency ${SWIFT_STDLIB_LIBRARY_BUILD_TYPES} IS_STDLIB
   ${SWIFT_RUNTIME_CONCURRENCY_C_SOURCES}
   ${SWIFT_RUNTIME_CONCURRENCY_EXECUTOR_SOURCES}
@@ -229,6 +237,7 @@ add_swift_target_library(swift_Concurrency ${SWIFT_STDLIB_LIBRARY_BUILD_TYPES} I
   GYB_SOURCES
     ${SWIFT_CONCURRENCY_GYB_SOURCES}
 
+  SWIFT_MODULE_DEPENDS ${SWIFT_CONCURRENCY_DEPENDENCIES}
   SWIFT_MODULE_DEPENDS_ANDROID Android
   SWIFT_MODULE_DEPENDS_LINUX Glibc
   SWIFT_MODULE_DEPENDS_LINUX_STATIC Musl