Fixed warnings.

diff --git a/dlls/ole32/hglobalstream.c b/dlls/ole32/hglobalstream.c
index bc025cb..2941af3 100644
--- a/dlls/ole32/hglobalstream.c
+++ b/dlls/ole32/hglobalstream.c
@@ -249,7 +249,7 @@
     /*
      * This method will allocate a handle if one is not supplied.
      */
-    if (newStream->supportHandle == NULL)
+    if (!newStream->supportHandle)
     {
       newStream->supportHandle = GlobalAlloc(GMEM_MOVEABLE | GMEM_NODISCARD |
 					     GMEM_SHARE, 0);
diff --git a/dlls/ole32/stg_bigblockfile.c b/dlls/ole32/stg_bigblockfile.c
index d67a3cf..8215b91 100644
--- a/dlls/ole32/stg_bigblockfile.c
+++ b/dlls/ole32/stg_bigblockfile.c
@@ -213,7 +213,7 @@
                                       0, 0,
                                       NULL);
 
-  if (This->hfilemap == NULL)
+  if (!This->hfilemap)
   {
     CloseHandle(This->hfile);
     return FALSE;
@@ -237,7 +237,7 @@
 static BOOL BIGBLOCKFILE_MemInit(LPBIGBLOCKFILE This, ILockBytes* plkbyt)
 {
   This->hfile       = 0;
-  This->hfilemap    = NULL;
+  This->hfilemap    = 0;
 
   /*
    * Retrieve the handle to the byte array from the LockByte object.
@@ -404,7 +404,7 @@
      * close file-mapping object, must be done before call to SetEndFile
      */
     CloseHandle(This->hfilemap);
-    This->hfilemap = NULL;
+    This->hfilemap = 0;
 
     /*
      * BEGIN HACK