Index: src/os_win.c
==================================================================
--- src/os_win.c
+++ src/os_win.c
@@ -944,11 +944,12 @@
     }
   }
   for(i=strlen(zTempPath); i>0 && zTempPath[i-1]=='\\'; i--){}
   zTempPath[i] = 0;
   for(;;){
-    sqlite3_snprintf(sizeof(zBuf), zBuf, "%s\\"TEMP_FILE_PREFIX, zTempPath);
+    sqlite3_snprintf(SQLITE_TEMPNAME_SIZE, zBuf,
+                     "%s\\"TEMP_FILE_PREFIX, zTempPath);
     j = strlen(zBuf);
     sqlite3Randomness(15, &zBuf[j]);
     for(i=0; i<15; i++, j++){
       zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
     }