From ea7d87b5b59ded22b145ecbb4dd648ecfd1abbdd Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?M=C3=A5rten=20Nordheim?= Date: Wed, 16 Jun 2021 11:40:04 +0200 Subject: QHash: Fix erase() edge-case When the element you want to erase is the last element AND the next element (element 0), when rehashed, would be relocated to the last element, this leads to the state below. Which is similar to a test in tst_qhash for some seeds. auto it = hash.begin + (hash.size - 1) it = hash.erase(it) it != hash.end By forcing the iterator to increment if we were erasing the last element we always end up with a pointer which is equal to hash.end Befriend the tst_qhash class so we can set the seed to a known-bad one Pick-to: 6.2 6.1 Change-Id: Ie0b175003a2acb175ef5e3ab5a984e010f65d986 Reviewed-by: Qt CI Bot Reviewed-by: Lars Knoll --- tests/auto/corelib/tools/qhash/tst_qhash.cpp | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) (limited to 'tests/auto/corelib') diff --git a/tests/auto/corelib/tools/qhash/tst_qhash.cpp b/tests/auto/corelib/tools/qhash/tst_qhash.cpp index d77160ba19..6ad7d15c77 100644 --- a/tests/auto/corelib/tools/qhash/tst_qhash.cpp +++ b/tests/auto/corelib/tools/qhash/tst_qhash.cpp @@ -42,6 +42,7 @@ class tst_QHash : public QObject private slots: void insert1(); void erase(); + void erase_edge_case(); void key(); void swap(); @@ -532,6 +533,24 @@ void tst_QHash::erase() QVERIFY(mit == h2.end()); } +/* + With a specific seed we could end up in a situation where, upon deleting the + last entry in a QHash, the returned iterator would not point to the end() + iterator. +*/ +void tst_QHash::erase_edge_case() +{ + QHash h1; + h1.reserve(2); + h1.d->seed = 10230148258692185509ull; + h1.insert(3, 4); + h1.insert(5, 6); + QHash::iterator it1 = h1.begin(); + ++it1; + it1 = h1.erase(it1); + QVERIFY(it1 == h1.end()); +} + void tst_QHash::key() { { -- cgit v1.2.3