Use INVALID_FILE_ATTRIBUTES to test for failure of
GetFileAttributesA/W and not -1 or 0xFFFFFFFF.

diff --git a/dlls/msvcrt/dir.c b/dlls/msvcrt/dir.c
index 4343461..a5ba3da 100644
--- a/dlls/msvcrt/dir.c
+++ b/dlls/msvcrt/dir.c
@@ -900,7 +900,7 @@
   *buf = '\0';
 
   /* Try CWD first */
-  if (GetFileAttributesA( file ) != 0xFFFFFFFF)
+  if (GetFileAttributesA( file ) != INVALID_FILE_ATTRIBUTES)
   {
     GetFullPathNameA( file, MAX_PATH, buf, NULL );
     /* Sigh. This error is *always* set, regardless of success */
@@ -940,7 +940,7 @@
 
     strcat(curPath, file);
     TRACE("Checking for file %s\n", curPath);
-    if (GetFileAttributesA( curPath ) != 0xFFFFFFFF)
+    if (GetFileAttributesA( curPath ) != INVALID_FILE_ATTRIBUTES)
     {
       strcpy(buf, curPath);
       MSVCRT__set_errno(ERROR_FILE_NOT_FOUND);