diff --git a/dlls/api-ms-win-crt-convert-l1-1-0/api-ms-win-crt-convert-l1-1-0.spec b/dlls/api-ms-win-crt-convert-l1-1-0/api-ms-win-crt-convert-l1-1-0.spec
index e2b5ab9877b..29b7a4c1476 100644
--- a/dlls/api-ms-win-crt-convert-l1-1-0/api-ms-win-crt-convert-l1-1-0.spec
+++ b/dlls/api-ms-win-crt-convert-l1-1-0/api-ms-win-crt-convert-l1-1-0.spec
@@ -57,7 +57,7 @@
 @ stub _wcstoimax_l
 @ cdecl _wcstol_l(wstr ptr long ptr) ucrtbase._wcstol_l
 @ stub _wcstold_l
-@ stub _wcstoll_l
+@ cdecl -ret64 _wcstoll_l(wstr ptr long ptr) ucrtbase._wcstoll_l
 @ cdecl _wcstombs_l(ptr ptr long ptr) ucrtbase._wcstombs_l
 @ cdecl _wcstombs_s_l(ptr ptr long wstr long ptr) ucrtbase._wcstombs_s_l
 @ cdecl -ret64 _wcstoui64(wstr ptr long) ucrtbase._wcstoui64
@@ -110,7 +110,7 @@
 @ stub wcstoimax
 @ cdecl wcstol(wstr ptr long) ucrtbase.wcstol
 @ stub wcstold
-@ stub wcstoll
+@ cdecl -ret64 wcstoll(wstr ptr long) ucrtbase.wcstoll
 @ cdecl wcstombs(ptr ptr long) ucrtbase.wcstombs
 @ cdecl wcstombs_s(ptr ptr long wstr long) ucrtbase.wcstombs_s
 @ cdecl wcstoul(wstr ptr long) ucrtbase.wcstoul
diff --git a/dlls/msvcr120/msvcr120.spec b/dlls/msvcr120/msvcr120.spec
index 0ac1de877f4..f65d1501684 100644
--- a/dlls/msvcr120/msvcr120.spec
+++ b/dlls/msvcr120/msvcr120.spec
@@ -1894,7 +1894,7 @@
 @ stub _wcstoimax_l
 @ cdecl _wcstol_l(wstr ptr long ptr) MSVCRT__wcstol_l
 @ stub _wcstold_l
-@ stub _wcstoll_l
+@ cdecl -ret64 _wcstoll_l(wstr ptr long ptr) MSVCRT__wcstoi64_l
 @ cdecl _wcstombs_l(ptr ptr long ptr) MSVCRT__wcstombs_l
 @ cdecl _wcstombs_s_l(ptr ptr long wstr long ptr) MSVCRT__wcstombs_s_l
 @ cdecl -ret64 _wcstoui64(wstr ptr long) MSVCRT__wcstoui64
@@ -2476,7 +2476,7 @@
 @ cdecl wcstok_s(ptr wstr ptr) MSVCRT_wcstok_s
 @ cdecl wcstol(wstr ptr long) ntdll.wcstol
 @ stub wcstold
-@ stub wcstoll
+@ cdecl -ret64 wcstoll(wstr ptr long) MSVCRT__wcstoi64
 @ cdecl wcstombs(ptr ptr long) MSVCRT_wcstombs
 @ cdecl wcstombs_s(ptr ptr long wstr long) MSVCRT_wcstombs_s
 @ cdecl wcstoul(wstr ptr long) MSVCRT_wcstoul
diff --git a/dlls/msvcr120_app/msvcr120_app.spec b/dlls/msvcr120_app/msvcr120_app.spec
index 99e1fa9f8d1..de68b87d533 100644
--- a/dlls/msvcr120_app/msvcr120_app.spec
+++ b/dlls/msvcr120_app/msvcr120_app.spec
@@ -1587,7 +1587,7 @@
 @ stub _wcstoimax_l
 @ cdecl _wcstol_l(wstr ptr long ptr) msvcr120._wcstol_l
 @ stub _wcstold_l
-@ stub _wcstoll_l
+@ cdecl -ret64 _wcstoll_l(wstr ptr long ptr) msvcr120._wcstoll_l
 @ cdecl _wcstombs_l(ptr ptr long ptr) msvcr120._wcstombs_l
 @ cdecl _wcstombs_s_l(ptr ptr long wstr long ptr) msvcr120._wcstombs_s_l
 @ cdecl -ret64 _wcstoui64(wstr ptr long) msvcr120._wcstoui64
@@ -2138,7 +2138,7 @@
 @ cdecl wcstok_s(ptr wstr ptr) msvcr120.wcstok_s
 @ cdecl wcstol(wstr ptr long) msvcr120.wcstol
 @ stub wcstold
-@ stub wcstoll
+@ cdecl -ret64 wcstoll(wstr ptr long) msvcr120.wcstoll
 @ cdecl wcstombs(ptr ptr long) msvcr120.wcstombs
 @ cdecl wcstombs_s(ptr ptr long wstr long) msvcr120.wcstombs_s
 @ cdecl wcstoul(wstr ptr long) msvcr120.wcstoul
diff --git a/dlls/ucrtbase/ucrtbase.spec b/dlls/ucrtbase/ucrtbase.spec
index 7582ba9b263..bb18d4f15e0 100644
--- a/dlls/ucrtbase/ucrtbase.spec
+++ b/dlls/ucrtbase/ucrtbase.spec
@@ -2043,7 +2043,7 @@
 @ stub _wcstoimax_l
 @ cdecl _wcstol_l(wstr ptr long ptr) MSVCRT__wcstol_l
 @ stub _wcstold_l
-@ stub _wcstoll_l
+@ cdecl -ret64 _wcstoll_l(wstr ptr long ptr) MSVCRT__wcstoi64_l
 @ cdecl _wcstombs_l(ptr ptr long ptr) MSVCRT__wcstombs_l
 @ cdecl _wcstombs_s_l(ptr ptr long wstr long ptr) MSVCRT__wcstombs_s_l
 @ cdecl -ret64 _wcstoui64(wstr ptr long) MSVCRT__wcstoui64
@@ -2583,7 +2583,7 @@
 @ cdecl wcstok_s(ptr wstr ptr) MSVCRT_wcstok_s
 @ cdecl wcstol(wstr ptr long) ntdll.wcstol
 @ stub wcstold
-@ stub wcstoll
+@ cdecl -ret64 wcstoll(wstr ptr long) MSVCRT__wcstoi64
 @ cdecl wcstombs(ptr ptr long) MSVCRT_wcstombs
 @ cdecl wcstombs_s(ptr ptr long wstr long) MSVCRT_wcstombs_s
 @ cdecl wcstoul(wstr ptr long) MSVCRT_wcstoul