diff --git a/dlls/kernel32/tests/comm.c b/dlls/kernel32/tests/comm.c
index 290cf81d33a..97a71358fef 100644
--- a/dlls/kernel32/tests/comm.c
+++ b/dlls/kernel32/tests/comm.c
@@ -410,8 +410,6 @@ static const TEST test[] =
 	},
 };
 
-#define TEST_COUNT (sizeof(test) / sizeof(TEST))
-
 /* This function can be useful if you are modifying the test cases and want to
    output the contents of a DCB structure. */
 /*static print_dcb(DCB *pdcb)
@@ -656,7 +654,7 @@ static void test_BuildCommDCB(void)
 	if(!port)
 		trace("Could not find a valid COM port.  Some tests will be skipped.\n");
 
-	for(i = 0; i < TEST_COUNT; i++)
+        for(i = 0; i < ARRAY_SIZE(test); i++)
 	{
                 char string[sizeof(test[i].string)];
 
diff --git a/dlls/kernel32/tests/toolhelp.c b/dlls/kernel32/tests/toolhelp.c
index c40dbc4f8fe..bdb01b9824d 100644
--- a/dlls/kernel32/tests/toolhelp.c
+++ b/dlls/kernel32/tests/toolhelp.c
@@ -217,8 +217,6 @@ static const char* sub_expected_modules[] =
     "ntdll.dll"
 };
 
-#define NUM_OF(x) (sizeof(x) / sizeof(x[0]))
-
 static void test_module(DWORD pid, const char* expected[], unsigned num_expected)
 {
     HANDLE              hSnapshot;
@@ -229,7 +227,7 @@ static void test_module(DWORD pid, const char* expected[], unsigned num_expected
     unsigned            i;
     int                 num = 0;
 
-    ok(NUM_OF(found) >= num_expected, "Internal: bump found[] size\n");
+    ok(ARRAY_SIZE(found) >= num_expected, "Internal: bump found[] size\n");
 
     hSnapshot = pCreateToolhelp32Snapshot( TH32CS_SNAPMODULE, pid );
     ok(hSnapshot != NULL, "Cannot create snapshot\n");
@@ -341,8 +339,8 @@ START_TEST(toolhelp)
 
     test_process(pid, info.dwProcessId);
     test_thread(pid, info.dwProcessId);
-    test_module(pid, curr_expected_modules, NUM_OF(curr_expected_modules));
-    test_module(info.dwProcessId, sub_expected_modules, NUM_OF(sub_expected_modules));
+    test_module(pid, curr_expected_modules, ARRAY_SIZE(curr_expected_modules));
+    test_module(info.dwProcessId, sub_expected_modules, ARRAY_SIZE(sub_expected_modules));
 
     SetEvent(ev2);
     winetest_wait_child_process( info.hProcess );