msvcp140: Pad _Mtx_t struct to match Windows.

dlls/msvcp140/tests/msvcp140.c

@@ -168,6 +168,7 @@ typedef struct
 {
     DWORD flags;
     critical_section cs;
+    ULONG_PTR unknown;
     DWORD thread_id;
     DWORD count;
 } *_Mtx_t;
@@ -1640,6 +1641,35 @@ static void test_Copy_file(void)
     ok(SetCurrentDirectoryW(origin_path), "SetCurrentDirectoryW to origin_path failed\n");
 }
 
+static void test__Mtx(void)
+{
+    _Mtx_t mtx = NULL;
+    int r;
+
+    r = p__Mtx_init(&mtx, 0);
+    ok(!r, "failed to init mtx\n");
+
+    ok(mtx->thread_id == -1, "mtx.thread_id = %lx\n", mtx->thread_id);
+    ok(mtx->count == 0, "mtx.count = %lx\n", mtx->count);
+    p__Mtx_lock(mtx);
+    ok(mtx->thread_id == GetCurrentThreadId(), "mtx.thread_id = %lx\n", mtx->thread_id);
+    ok(mtx->count == 1, "mtx.count = %lx\n", mtx->count);
+    p__Mtx_lock(mtx);
+    ok(mtx->thread_id == GetCurrentThreadId(), "mtx.thread_id = %lx\n", mtx->thread_id);
+    ok(mtx->count == 1, "mtx.count = %lx\n", mtx->count);
+    p__Mtx_unlock(mtx);
+    ok(mtx->thread_id == -1, "mtx.thread_id = %lx\n", mtx->thread_id);
+    ok(mtx->count == 0, "mtx.count = %lx\n", mtx->count);
+    p__Mtx_unlock(mtx);
+    ok(mtx->thread_id == -1, "mtx.thread_id = %lx\n", mtx->thread_id);
+    ok(mtx->count == -1, "mtx.count = %lx\n", mtx->count);
+    p__Mtx_unlock(mtx);
+    ok(mtx->thread_id == -1, "mtx.thread_id = %lx\n", mtx->thread_id);
+    ok(mtx->count == -2, "mtx.count = %lx\n", mtx->count);
+
+    p__Mtx_destroy(mtx);
+}
+
 START_TEST(msvcp140)
 {
     if(!init()) return;
@@ -1667,5 +1697,6 @@ START_TEST(msvcp140)
     test_Equivalent();
     test_cnd();
     test_Copy_file();
+    test__Mtx();
     FreeLibrary(msvcp);
 }

dlls/msvcp90/misc.c

@@ -716,6 +716,9 @@ typedef struct
 {
     DWORD flags;
     cs cs;
+#if _MSVCP_VER >= 140
+    ULONG_PTR unknown;
+#endif
     DWORD thread_id;
     DWORD count;
 } *_Mtx_t;