diff --git a/dlls/concrt140/concrt140.spec b/dlls/concrt140/concrt140.spec
index dd8d13a2e39..d510a3b9371 100644
--- a/dlls/concrt140/concrt140.spec
+++ b/dlls/concrt140/concrt140.spec
@@ -217,8 +217,8 @@
 @ stub -arch=i386 ??_F_Scheduler@details@Concurrency@@QAEXXZ
 @ stub -arch=win64 ??_F_Scheduler@details@Concurrency@@QEAAXXZ
 # extern ?AgentEventGuid@Concurrency@@3U_GUID@@B
-@ stub -arch=win32 ?Alloc@Concurrency@@YAPAXI@Z
-@ stub -arch=win64 ?Alloc@Concurrency@@YAPEAX_K@Z
+@ cdecl -arch=win32 ?Alloc@Concurrency@@YAPAXI@Z(long) msvcr120.?Alloc@Concurrency@@YAPAXI@Z
+@ cdecl -arch=win64 ?Alloc@Concurrency@@YAPEAX_K@Z(long) msvcr120.?Alloc@Concurrency@@YAPEAX_K@Z
 @ stub -arch=win64 ?Block@Context@Concurrency@@SAXXZ
 # extern ?ChoreEventGuid@Concurrency@@3U_GUID@@B
 # extern ?ConcRTEventGuid@Concurrency@@3U_GUID@@B
diff --git a/dlls/msvcr100/msvcr100.spec b/dlls/msvcr100/msvcr100.spec
index 729d16f2144..38753047980 100644
--- a/dlls/msvcr100/msvcr100.spec
+++ b/dlls/msvcr100/msvcr100.spec
@@ -242,8 +242,8 @@
 @ cdecl -arch=win64 ??_U@YAPEAX_KHPEBDH@Z(long long str long) MSVCRT_operator_new_dbg
 @ cdecl -arch=win32 ??_V@YAXPAX@Z(ptr) MSVCRT_operator_delete
 @ cdecl -arch=win64 ??_V@YAXPEAX@Z(ptr) MSVCRT_operator_delete
-@ stub -arch=win32 ?Alloc@Concurrency@@YAPAXI@Z
-@ stub -arch=win64 ?Alloc@Concurrency@@YAPEAX_K@Z
+@ cdecl -arch=win32 ?Alloc@Concurrency@@YAPAXI@Z(long) Concurrency_Alloc
+@ cdecl -arch=win64 ?Alloc@Concurrency@@YAPEAX_K@Z(long) Concurrency_Alloc
 @ stub ?Block@Context@Concurrency@@SAXXZ
 @ stub -arch=win32 ?Create@CurrentScheduler@Concurrency@@SAXABVSchedulerPolicy@2@@Z
 @ stub -arch=win64 ?Create@CurrentScheduler@Concurrency@@SAXAEBVSchedulerPolicy@2@@Z
diff --git a/dlls/msvcr110/msvcr110.spec b/dlls/msvcr110/msvcr110.spec
index fa3206d1e95..4026b1baed7 100644
--- a/dlls/msvcr110/msvcr110.spec
+++ b/dlls/msvcr110/msvcr110.spec
@@ -400,8 +400,8 @@
 @ cdecl -arch=win64 ??_V@YAXPEAX@Z(ptr) MSVCRT_operator_delete
 @ stub -arch=win32 ??_V@YAXPAXHPBDH@Z
 @ stub -arch=win64 ??_V@YAXPEAXHPEBDH@Z
-@ stub -arch=win32 ?Alloc@Concurrency@@YAPAXI@Z
-@ stub -arch=win64 ?Alloc@Concurrency@@YAPEAX_K@Z
+@ cdecl -arch=win32 ?Alloc@Concurrency@@YAPAXI@Z(long) Concurrency_Alloc
+@ cdecl -arch=win64 ?Alloc@Concurrency@@YAPEAX_K@Z(long) Concurrency_Alloc
 @ stub ?Block@Context@Concurrency@@SAXXZ
 @ stub -arch=win32 ?Create@CurrentScheduler@Concurrency@@SAXABVSchedulerPolicy@2@@Z
 @ stub -arch=win64 ?Create@CurrentScheduler@Concurrency@@SAXAEBVSchedulerPolicy@2@@Z
diff --git a/dlls/msvcr120/msvcr120.spec b/dlls/msvcr120/msvcr120.spec
index 84edf51369d..27c800ba7d6 100644
--- a/dlls/msvcr120/msvcr120.spec
+++ b/dlls/msvcr120/msvcr120.spec
@@ -396,8 +396,8 @@
 @ cdecl -arch=win64 ??_V@YAXPEAX@Z(ptr) MSVCRT_operator_delete
 @ stub -arch=win32 ??_V@YAXPAXHPBDH@Z
 @ stub -arch=win64 ??_V@YAXPEAXHPEBDH@Z
-@ stub -arch=win32 ?Alloc@Concurrency@@YAPAXI@Z
-@ stub -arch=win64 ?Alloc@Concurrency@@YAPEAX_K@Z
+@ cdecl -arch=win32 ?Alloc@Concurrency@@YAPAXI@Z(long) Concurrency_Alloc
+@ cdecl -arch=win64 ?Alloc@Concurrency@@YAPEAX_K@Z(long) Concurrency_Alloc
 @ stub ?Block@Context@Concurrency@@SAXXZ
 @ stub -arch=win32 ?CaptureCallstack@platform@details@Concurrency@@YAIPAPAXII@Z
 @ stub -arch=win64 ?CaptureCallstack@platform@details@Concurrency@@YA_KPEAPEAX_K1@Z
diff --git a/dlls/msvcr120_app/msvcr120_app.spec b/dlls/msvcr120_app/msvcr120_app.spec
index 46a76da1c8e..dcb391c9465 100644
--- a/dlls/msvcr120_app/msvcr120_app.spec
+++ b/dlls/msvcr120_app/msvcr120_app.spec
@@ -393,8 +393,8 @@
 @ cdecl -arch=win64 ??_V@YAXPEAX@Z(ptr) msvcr120.??_V@YAXPEAX@Z
 @ stub -arch=win32 ??_V@YAXPAXHPBDH@Z
 @ stub -arch=win64 ??_V@YAXPEAXHPEBDH@Z
-@ stub -arch=win32 ?Alloc@Concurrency@@YAPAXI@Z
-@ stub -arch=win64 ?Alloc@Concurrency@@YAPEAX_K@Z
+@ cdecl -arch=win32 ?Alloc@Concurrency@@YAPAXI@Z(long) msvcr120.?Alloc@Concurrency@@YAPAXI@Z
+@ cdecl -arch=win64 ?Alloc@Concurrency@@YAPEAX_K@Z(long) msvcr120.?Alloc@Concurrency@@YAPEAX_K@Z
 @ stub ?Block@Context@Concurrency@@SAXXZ
 @ stub ?CaptureCallstack@platform@details@Concurrency@@YAIPAPAXII@Z
 @ stub -arch=win32 ?Create@CurrentScheduler@Concurrency@@SAXABVSchedulerPolicy@2@@Z
diff --git a/dlls/msvcrt/heap.c b/dlls/msvcrt/heap.c
index 3ae25990b41..f99f9c3e6c7 100644
--- a/dlls/msvcrt/heap.c
+++ b/dlls/msvcrt/heap.c
@@ -864,3 +864,12 @@ void msvcrt_destroy_heap(void)
     if(sb_heap)
         HeapDestroy(sb_heap);
 }
+
+/* ?Alloc@Concurrency@@YAPAXI@Z */
+/* ?Alloc@Concurrency@@YAPEAX_K@Z */
+void * CDECL Concurrency_Alloc(MSVCRT_size_t size)
+{
+    void *p = MSVCRT_malloc(size);
+    FIXME("(%ld) returning %p\n", size, p);
+    return p;
+}