From 34d17c9ea18f43abfc7eefa48fa862a611dccfa2 Mon Sep 17 00:00:00 2001
From: Marcus Meissner <marcus@jet.franken.de>
Date: Sun, 23 May 2010 13:33:40 +0200
Subject: [PATCH] ntdll: qsort: comparator must not get the same pointer.

---
 dlls/ntdll/misc.c         | 2 +-
 dlls/ntdll/tests/string.c | 3 +++
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/dlls/ntdll/misc.c b/dlls/ntdll/misc.c
index 621848ee021..2d7c0a7ee8b 100644
--- a/dlls/ntdll/misc.c
+++ b/dlls/ntdll/misc.c
@@ -272,7 +272,7 @@ NTDLL_mergesort( void *arr, void *barr, int elemsize, int(__cdecl *compar)(const
 
         for (k=left; k<=right; k++) {
             /*arr[k]=(barr[i]<barr[j])?barr[i++]:barr[j--];*/
-            if (compar(X(barr,i),X(barr,j))<0) {
+            if (i != j && compar(X(barr,i),X(barr,j))<0) {
                 memcpy(X(arr,k),X(barr,i),elemsize);
                 i++;
             } else {
diff --git a/dlls/ntdll/tests/string.c b/dlls/ntdll/tests/string.c
index cd362ed7a12..3f7236a3dfe 100644
--- a/dlls/ntdll/tests/string.c
+++ b/dlls/ntdll/tests/string.c
@@ -1145,16 +1145,19 @@ static void test_wcsrchr(void)
 
 static __cdecl int intcomparefunc(const void *a, const void*b)
 {
+	ok (a != b, "must never get the same pointer\n");
 	return (*(int*)a) - (*(int*)b);
 }
 
 static __cdecl int charcomparefunc(const void *a, const void*b)
 {
+	ok (a != b, "must never get the same pointer\n");
 	return (*(char*)a) - (*(char*)b);
 }
 
 static __cdecl int strcomparefunc(const void *a, const void*b)
 {
+	ok (a != b, "must never get the same pointer\n");
 	return lstrcmpA(*(char**)a,*(char**)b);
 }
 
-- 
2.11.4.GIT