stdlib: restrict pthreads to POSIX platforms

pthreads is not available on non-POSIX platforms (i.e. Windows).  Restrict the
target platforms that we build SwiftPrivatePthreadExtras and things which depend
on it.

Author: compnerd

stdlib/private/StdlibCollectionUnittest/CMakeLists.txt

@@ -9,6 +9,8 @@ if(SWIFT_HOST_VARIANT MATCHES "${SWIFT_DARWIN_VARIANTS}")
     Foundation)
 endif()
 
+# TODO: support this on non-POSIX platforms.  It cannot be currently as it
+# depends on pthreads.
 add_swift_library(swiftStdlibCollectionUnittest ${SWIFT_STDLIB_LIBRARY_BUILD_TYPES} IS_STDLIB
   # This file should be listed the first.  Module name is inferred from the
   # filename.
@@ -28,6 +30,7 @@ add_swift_library(swiftStdlibCollectionUnittest ${SWIFT_STDLIB_LIBRARY_BUILD_TYP
 
   SWIFT_MODULE_DEPENDS StdlibUnittest
   SWIFT_COMPILE_FLAGS ${swift_stdlib_unittest_compile_flags}
+  TARGET_SDKS ALL_POSIX_PLATFORMS
   FRAMEWORK_DEPENDS ${swift_stdlib_unittest_framework_depends}
   INSTALL_IN_COMPONENT stdlib-experimental)
 

stdlib/private/StdlibUnittest/CMakeLists.txt

@@ -14,6 +14,8 @@ if(SWIFT_HOST_VARIANT MATCHES "${SWIFT_DARWIN_VARIANTS}")
   list(APPEND swift_stdlib_unittest_framework_depends Foundation)
 endif()
 
+# TODO: support this on non-POSIX platforms.  It cannot be currently as it
+# depends on pthreads.
 add_swift_library(swiftStdlibUnittest ${SWIFT_STDLIB_LIBRARY_BUILD_TYPES} IS_STDLIB
   # This file should be listed the first.  Module name is inferred from the
   # filename.
@@ -40,6 +42,7 @@ add_swift_library(swiftStdlibUnittest ${SWIFT_STDLIB_LIBRARY_BUILD_TYPES} IS_STD
   SWIFT_MODULE_DEPENDS_LINUX Glibc
   SWIFT_MODULE_DEPENDS_FREEBSD Glibc
   SWIFT_COMPILE_FLAGS ${swift_stdlib_unittest_compile_flags}
+  TARGET_SDKS ALL_POSIX_PLATFORMS
   FRAMEWORK_DEPENDS ${swift_stdlib_unittest_framework_depends}
   INSTALL_IN_COMPONENT stdlib-experimental)
 

stdlib/private/SwiftPrivatePthreadExtras/CMakeLists.txt

@@ -11,5 +11,6 @@ add_swift_library(swiftSwiftPrivatePthreadExtras ${SWIFT_STDLIB_LIBRARY_BUILD_TY
   SWIFT_MODULE_DEPENDS_LINUX Glibc
   SWIFT_MODULE_DEPENDS_FREEBSD Glibc
   SWIFT_COMPILE_FLAGS ${STDLIB_SIL_SERIALIZE_ALL}
+  TARGET_SDKS ALL_POSIX_PLATFORMS
   INSTALL_IN_COMPONENT stdlib-experimental)