ghc-internal: add missing CPPs for wasm

This patch adds some missing CPP guards to ghc-internal, given those
functions are non existent on wasm and would cause linking issues.

(cherry picked from commit a998f69d)

libraries/ghc-internal/src/GHC/Internal/Conc/Bound.hs

@@ -112,13 +112,21 @@ forkOS_entry stableAction = do
         action <- deRefStablePtr stableAction
         action
 
-foreign import ccall forkOS_createThread
-    :: StablePtr (IO ()) -> IO CInt
+
 
 failNonThreaded :: IO a
 failNonThreaded = fail $ "RTS doesn't support multiple OS threads "
                        ++"(use ghc -threaded when linking)"
 
+#if defined(wasm32_HOST_ARCH)
+
+forkOS _ = failNonThreaded
+
+#else
+
+foreign import ccall forkOS_createThread
+    :: StablePtr (IO ()) -> IO CInt
+
 forkOS action0
     | rtsSupportsBoundThreads = do
         mv <- newEmptyMVar
@@ -141,6 +149,7 @@ forkOS action0
         freeStablePtr entry
         return tid
     | otherwise = failNonThreaded
+#endif
 
 -- | Like 'forkIOWithUnmask', but the child thread is a bound thread,
 -- as with 'forkOS'.

libraries/ghc-internal/src/GHC/Internal/System/Posix/Internals.hs

@@ -732,8 +732,13 @@ foreign import capi unsafe "HsBase.h read"
 foreign import capi safe "HsBase.h read"
    c_safe_read :: CInt -> Ptr Word8 -> CSize -> IO CSsize
 
+#if !defined(HAVE_UMASK)
+c_umask :: CMode -> IO CMode
+c_umask _ = ioError (ioeSetLocation unsupportedOperation "umask")
+#else
 foreign import ccall unsafe "HsBase.h umask"
    c_umask :: CMode -> IO CMode
+#endif
 
 -- See Note [Windows types]
 foreign import capi unsafe "HsBase.h write"