diff --git a/src/estream.c b/src/estream.c
--- a/src/estream.c
+++ b/src/estream.c
@@ -152,7 +152,7 @@
 #endif
 
 #ifdef HAVE_W32_SYSTEM
-# define IS_INVALID_FD(a)    ((void*)(a) == (void*)(-1)) /* ?? FIXME.  */
+# define IS_INVALID_FD(a)    ((intptr_t)(a) == (-1))
 #else
 # define IS_INVALID_FD(a)    ((a) == -1)
 #endif
@@ -4531,7 +4531,7 @@
 #ifdef HAVE_W32CE_SYSTEM
           int fd = (int)file;
 #else
-          int fd = _open_osfhandle ((long)file, 0);
+          int fd = _open_osfhandle ((intptr_t)file, 0);
           if (fd == -1)
             {
               CloseHandle (file);
diff --git a/src/spawn-w32.c b/src/spawn-w32.c
--- a/src/spawn-w32.c
+++ b/src/spawn-w32.c
@@ -62,9 +62,9 @@
  * FIXME: With Windows 64 this is no longer true.
  */
 #define fd_to_handle(a)  ((HANDLE)(a))
-#define handle_to_fd(a)  ((int)(a))
+#define handle_to_fd(a)  ((intptr_t)(a))
 #define pid_to_handle(a) ((HANDLE)(a))
-#define handle_to_pid(a) ((int)(a))
+#define handle_to_pid(a) ((intptr_t)(a))
 
 
 /* Return the maximum number of currently allowed open file