diff --git a/win32/win32.c b/win32/win32.c
index 861e707760fa..4c98c1b50f32 100644
--- a/win32/win32.c
+++ b/win32/win32.c
@@ -1482,6 +1482,8 @@ time_t
 translate_ft_to_time_t(FILETIME ft) {
     SYSTEMTIME st, local_st;
     struct tm pt;
+    time_t retval;
+    dTHX;
 
     if (!FileTimeToSystemTime(&ft, &st) ||
         !SystemTimeToTzSpecificLocalTime(NULL, &st, &local_st)) {
@@ -1497,7 +1499,11 @@ translate_ft_to_time_t(FILETIME ft) {
     pt.tm_sec = local_st.wSecond;
     pt.tm_isdst = -1;
 
-    return mktime(&pt);
+    MKTIME_LOCK;
+    retval = mktime(&pt);
+    MKTIME_UNLOCK;
+
+    return retval;
 }
 
 typedef DWORD (__stdcall *pGetFinalPathNameByHandleA_t)(HANDLE, LPSTR, DWORD, DWORD);
@@ -2231,9 +2237,12 @@ filetime_from_time(PFILETIME pFileTime, time_t Time)
 {
     struct tm *pt;
     SYSTEMTIME st;
+    dTHX;
 
+    GMTIME_LOCK;
     pt = gmtime(&Time);
     if (!pt) {
+        GMTIME_UNLOCK;
         pFileTime->dwLowDateTime = 0;
         pFileTime->dwHighDateTime = 0;
         fprintf(stderr, "fail bad gmtime\n");
@@ -2248,6 +2257,8 @@ filetime_from_time(PFILETIME pFileTime, time_t Time)
     st.wSecond = pt->tm_sec;
     st.wMilliseconds = 0;
 
+    GMTIME_UNLOCK;
+
     if (!SystemTimeToFileTime(&st, pFileTime)) {
         pFileTime->dwLowDateTime = 0;
         pFileTime->dwHighDateTime = 0;