diff --git a/w32/subproc/sub_proc.c b/w32/subproc/sub_proc.c
index 2442411a..564ff1ae 100644
--- a/w32/subproc/sub_proc.c
+++ b/w32/subproc/sub_proc.c
@@ -677,6 +677,7 @@ process_begin(
         /*
          *  Set up inherited stdin, stdout, stderr for child
          */
+	memset(&startInfo, sizeof(startInfo));
         GetStartupInfo(&startInfo);
         startInfo.dwFlags = STARTF_USESTDHANDLES;
         startInfo.lpReserved = 0;