diff --git a/dlls/msvcr100/msvcr100.spec b/dlls/msvcr100/msvcr100.spec
index 9c20f28d6d0..72cf6f3624c 100644
--- a/dlls/msvcr100/msvcr100.spec
+++ b/dlls/msvcr100/msvcr100.spec
@@ -1516,7 +1516,7 @@
 @ cdecl -ret64 _wcstoui64_l(wstr ptr long ptr) MSVCRT__wcstoui64_l
 @ cdecl _wcstoul_l(wstr ptr long ptr) MSVCRT__wcstoul_l
 @ cdecl _wcsupr(wstr) ntdll._wcsupr
-@ stub _wcsupr_l
+@ cdecl _wcsupr_l(wstr ptr) MSVCRT__wcsupr_l
 @ cdecl _wcsupr_s(wstr long) MSVCRT__wcsupr_s
 @ cdecl _wcsupr_s_l(wstr long ptr) MSVCRT__wcsupr_s_l
 @ stub _wcsxfrm_l
diff --git a/dlls/msvcr110/msvcr110.spec b/dlls/msvcr110/msvcr110.spec
index 0034b2f0af4..3d24b0f608e 100644
--- a/dlls/msvcr110/msvcr110.spec
+++ b/dlls/msvcr110/msvcr110.spec
@@ -1875,7 +1875,7 @@
 @ cdecl -ret64 _wcstoui64_l(wstr ptr long ptr) MSVCRT__wcstoui64_l
 @ cdecl _wcstoul_l(wstr ptr long ptr) MSVCRT__wcstoul_l
 @ cdecl _wcsupr(wstr) ntdll._wcsupr
-@ stub _wcsupr_l
+@ cdecl _wcsupr_l(wstr ptr) MSVCRT__wcsupr_l
 @ cdecl _wcsupr_s(wstr long) MSVCRT__wcsupr_s
 @ cdecl _wcsupr_s_l(wstr long ptr) MSVCRT__wcsupr_s_l
 @ stub _wcsxfrm_l
diff --git a/dlls/msvcr80/msvcr80.spec b/dlls/msvcr80/msvcr80.spec
index 1caa7e015e9..ef70cf13c5d 100644
--- a/dlls/msvcr80/msvcr80.spec
+++ b/dlls/msvcr80/msvcr80.spec
@@ -1195,7 +1195,7 @@
 @ cdecl -ret64 _wcstoui64_l(wstr ptr long ptr) MSVCRT__wcstoui64_l
 @ cdecl _wcstoul_l(wstr ptr long ptr) MSVCRT__wcstoul_l
 @ cdecl _wcsupr(wstr) ntdll._wcsupr
-@ stub _wcsupr_l
+@ cdecl _wcsupr_l(wstr ptr) MSVCRT__wcsupr_l
 @ cdecl _wcsupr_s(wstr long) MSVCRT__wcsupr_s
 @ cdecl _wcsupr_s_l(wstr long ptr) MSVCRT__wcsupr_s_l
 @ stub _wcsxfrm_l
diff --git a/dlls/msvcr90/msvcr90.spec b/dlls/msvcr90/msvcr90.spec
index b624bd0fbc9..161d224e185 100644
--- a/dlls/msvcr90/msvcr90.spec
+++ b/dlls/msvcr90/msvcr90.spec
@@ -1171,7 +1171,7 @@
 @ cdecl -ret64 _wcstoui64_l(wstr ptr long ptr) MSVCRT__wcstoui64_l
 @ cdecl _wcstoul_l(wstr ptr long ptr) MSVCRT__wcstoul_l
 @ cdecl _wcsupr(wstr) ntdll._wcsupr
-@ stub _wcsupr_l
+@ cdecl _wcsupr_l(wstr ptr) MSVCRT__wcsupr_l
 @ cdecl _wcsupr_s(wstr long) MSVCRT__wcsupr_s
 @ cdecl _wcsupr_s_l(wstr long ptr) MSVCRT__wcsupr_s_l
 @ stub _wcsxfrm_l
diff --git a/dlls/msvcrt/msvcrt.spec b/dlls/msvcrt/msvcrt.spec
index 739914a73d7..a7d1a973dfb 100644
--- a/dlls/msvcrt/msvcrt.spec
+++ b/dlls/msvcrt/msvcrt.spec
@@ -1131,7 +1131,7 @@
 @ cdecl -ret64 _wcstoui64_l(wstr ptr long ptr) MSVCRT__wcstoui64_l
 @ cdecl _wcstoul_l(wstr ptr long ptr) MSVCRT__wcstoul_l
 @ cdecl _wcsupr(wstr) ntdll._wcsupr
-# stub _wcsupr_l(wstr ptr)
+@ cdecl _wcsupr_l(wstr ptr) MSVCRT__wcsupr_l
 @ cdecl _wcsupr_s(wstr long) MSVCRT__wcsupr_s
 @ cdecl _wcsupr_s_l(wstr long ptr) MSVCRT__wcsupr_s_l
 # stub _wcsxfrm_l(ptr wstr long ptr)
diff --git a/dlls/msvcrt/wcs.c b/dlls/msvcrt/wcs.c
index 37ca3fb9786..60a24a5b16e 100644
--- a/dlls/msvcrt/wcs.c
+++ b/dlls/msvcrt/wcs.c
@@ -225,6 +225,15 @@ INT CDECL MSVCRT__wcsupr_s( MSVCRT_wchar_t* str, MSVCRT_size_t n )
   return MSVCRT__wcsupr_s_l( str, n, NULL );
 }
 
+/******************************************************************
+ *              _wcsupr_l (MSVCRT.@)
+ */
+MSVCRT_wchar_t* CDECL MSVCRT__wcsupr_l( MSVCRT_wchar_t *str, MSVCRT__locale_t locale )
+{
+    MSVCRT__wcsupr_s_l( str, -1, locale);
+    return str;
+}
+
 /******************************************************************
  *		_wcslwr_s (MSVCRT.@)
  */