diff --git a/src/corelib/tools/qstring.cpp b/src/corelib/tools/qstring.cpp
index 58eb711168..79e3577727 100644
--- a/src/corelib/tools/qstring.cpp
+++ b/src/corelib/tools/qstring.cpp
@@ -3375,9 +3375,15 @@ QString QString::mid(int position, int n) const
 {
     if (position > d->size)
         return QString();
-    if (position < 0)
+    if (position < 0) {
+        if (n < 0 || n + position >= d->size)
+            return *this;
+        if (n + position <= 0)
+            return QString();
+
+        n += position;
         position = 0;
-    if (n < 0 || n > d->size - position)
+    } else if (n < 0 || n > d->size - position)
         n = d->size - position;
     if (position == 0 && n == d->size)
         return *this;
@@ -8040,9 +8046,15 @@ QStringRef QString::midRef(int position, int n) const
 {
     if (position > d->size)
         return QStringRef();
-    if (position < 0)
+    if (position < 0) {
+        if (n < 0 || n + position >= d->size)
+            return QStringRef(this, 0, d->size);
+        if (n + position <= 0)
+            return QStringRef();
+
+        n += position;
         position = 0;
-    if (n < 0 || n > d->size - position)
+    } else if (n < 0 || n > d->size - position)
         n = d->size - position;
     return QStringRef(this, position, n);
 }
diff --git a/tests/auto/corelib/tools/qstring/tst_qstring.cpp b/tests/auto/corelib/tools/qstring/tst_qstring.cpp
index a8f706ff80..355e4d7d00 100644
--- a/tests/auto/corelib/tools/qstring/tst_qstring.cpp
+++ b/tests/auto/corelib/tools/qstring/tst_qstring.cpp
@@ -1421,8 +1421,14 @@ void tst_QString::mid()
     QVERIFY(a.mid(9999).isNull());
     QVERIFY(a.mid(9999,1).isNull());
 
-    QCOMPARE(a.mid(-1, 6), QString("ABCDEF"));
-    QCOMPARE(a.mid(-100, 6), QString("ABCDEF"));
+    QCOMPARE(a.mid(-1, 6), a.mid(0, 5));
+    QVERIFY(a.mid(-100, 6).isEmpty());
+    QVERIFY(a.mid(INT_MIN, 0).isEmpty());
+    QCOMPARE(a.mid(INT_MIN, -1), a);
+    QVERIFY(a.mid(INT_MIN, INT_MAX).isNull());
+    QVERIFY(a.mid(INT_MIN + 1, INT_MAX).isEmpty());
+    QCOMPARE(a.mid(INT_MIN + 2, INT_MAX), a.left(1));
+    QCOMPARE(a.mid(INT_MIN + a.size() + 1, INT_MAX), a);
     QVERIFY(a.mid(INT_MAX).isNull());
     QVERIFY(a.mid(INT_MAX, INT_MAX).isNull());
     QCOMPARE(a.mid(-5, INT_MAX), a);
@@ -1441,6 +1447,12 @@ void tst_QString::mid()
 
     QVERIFY(n.mid(-1, 6).isNull());
     QVERIFY(n.mid(-100, 6).isNull());
+    QVERIFY(n.mid(INT_MIN, 0).isNull());
+    QVERIFY(n.mid(INT_MIN, -1).isNull());
+    QVERIFY(n.mid(INT_MIN, INT_MAX).isNull());
+    QVERIFY(n.mid(INT_MIN + 1, INT_MAX).isNull());
+    QVERIFY(n.mid(INT_MIN + 2, INT_MAX).isNull());
+    QVERIFY(n.mid(INT_MIN + n.size() + 1, INT_MAX).isNull());
     QVERIFY(n.mid(INT_MAX).isNull());
     QVERIFY(n.mid(INT_MAX, INT_MAX).isNull());
     QVERIFY(n.mid(-5, INT_MAX).isNull());
@@ -1455,8 +1467,14 @@ void tst_QString::mid()
     QCOMPARE(x.mid(5, 4), QString("pine"));
     QCOMPARE(x.mid(5), QString("pineapples"));
 
-    QCOMPARE(x.mid(-1, 6), QString("Nine p"));
-    QCOMPARE(x.mid(-100, 6), QString("Nine p"));
+    QCOMPARE(x.mid(-1, 6), x.mid(0, 5));
+    QVERIFY(x.mid(-100, 6).isEmpty());
+    QVERIFY(x.mid(INT_MIN, 0).isEmpty());
+    QCOMPARE(x.mid(INT_MIN, -1), x);
+    QVERIFY(x.mid(INT_MIN, INT_MAX).isNull());
+    QVERIFY(x.mid(INT_MIN + 1, INT_MAX).isEmpty());
+    QCOMPARE(x.mid(INT_MIN + 2, INT_MAX), x.left(1));
+    QCOMPARE(x.mid(INT_MIN + x.size() + 1, INT_MAX), x);
     QVERIFY(x.mid(INT_MAX).isNull());
     QVERIFY(x.mid(INT_MAX, INT_MAX).isNull());
     QCOMPARE(x.mid(-5, INT_MAX), x);
@@ -1482,8 +1500,14 @@ void tst_QString::midRef()
     QVERIFY(a.midRef(9999).toString().isEmpty());
     QVERIFY(a.midRef(9999,1).toString().isEmpty());
 
-    QCOMPARE(a.midRef(-1, 6).toString(), QString("ABCDEF"));
-    QCOMPARE(a.midRef(-100, 6).toString(), QString("ABCDEF"));
+    QCOMPARE(a.midRef(-1, 6), a.midRef(0, 5));
+    QVERIFY(a.midRef(-100, 6).isEmpty());
+    QVERIFY(a.midRef(INT_MIN, 0).isEmpty());
+    QCOMPARE(a.midRef(INT_MIN, -1).toString(), a);
+    QVERIFY(a.midRef(INT_MIN, INT_MAX).isNull());
+    QVERIFY(a.midRef(INT_MIN + 1, INT_MAX).isEmpty());
+    QCOMPARE(a.midRef(INT_MIN + 2, INT_MAX), a.leftRef(1));
+    QCOMPARE(a.midRef(INT_MIN + a.size() + 1, INT_MAX).toString(), a);
     QVERIFY(a.midRef(INT_MAX).isNull());
     QVERIFY(a.midRef(INT_MAX, INT_MAX).isNull());
     QCOMPARE(a.midRef(-5, INT_MAX).toString(), a);
@@ -1502,6 +1526,12 @@ void tst_QString::midRef()
 
     QVERIFY(n.midRef(-1, 6).isNull());
     QVERIFY(n.midRef(-100, 6).isNull());
+    QVERIFY(n.midRef(INT_MIN, 0).isNull());
+    QVERIFY(n.midRef(INT_MIN, -1).isNull());
+    QVERIFY(n.midRef(INT_MIN, INT_MAX).isNull());
+    QVERIFY(n.midRef(INT_MIN + 1, INT_MAX).isNull());
+    QVERIFY(n.midRef(INT_MIN + 2, INT_MAX).isNull());
+    QVERIFY(n.midRef(INT_MIN + n.size() + 1, INT_MAX).isNull());
     QVERIFY(n.midRef(INT_MAX).isNull());
     QVERIFY(n.midRef(INT_MAX, INT_MAX).isNull());
     QVERIFY(n.midRef(-5, INT_MAX).isNull());
@@ -1516,8 +1546,14 @@ void tst_QString::midRef()
     QCOMPARE(x.midRef(5, 4).toString(), QString("pine"));
     QCOMPARE(x.midRef(5).toString(), QString("pineapples"));
 
-    QCOMPARE(x.midRef(-1, 6).toString(), QString("Nine p"));
-    QCOMPARE(x.midRef(-100, 6).toString(), QString("Nine p"));
+    QCOMPARE(x.midRef(-1, 6), x.midRef(0, 5));
+    QVERIFY(x.midRef(-100, 6).isEmpty());
+    QVERIFY(x.midRef(INT_MIN, 0).isEmpty());
+    QCOMPARE(x.midRef(INT_MIN, -1).toString(), x);
+    QVERIFY(x.midRef(INT_MIN, INT_MAX).isNull());
+    QVERIFY(x.midRef(INT_MIN + 1, INT_MAX).isEmpty());
+    QCOMPARE(x.midRef(INT_MIN + 2, INT_MAX), x.leftRef(1));
+    QCOMPARE(x.midRef(INT_MIN + x.size() + 1, INT_MAX).toString(), x);
     QVERIFY(x.midRef(INT_MAX).isNull());
     QVERIFY(x.midRef(INT_MAX, INT_MAX).isNull());
     QCOMPARE(x.midRef(-5, INT_MAX).toString(), x);