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MathiasVPMathiasVP
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C++: Implement move constructor in terms of swap. I'm haven't found anything online on whether this is good or bad, and the only reason for not doing it might be performance.
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‎cpp/ql/test/library-tests/dataflow/taint-tests/localTaint.expected

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@@ -623,6 +623,14 @@
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| taint.cpp:483:18:483:19 | ref arg & ... | taint.cpp:483:19:483:19 | n [inner post update] | |
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| taint.cpp:483:19:483:19 | n | taint.cpp:483:18:483:19 | & ... | |
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| taint.cpp:483:28:483:34 | source1 | taint.cpp:483:11:483:15 | ref arg & ... | TAINT |
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| taint.cpp:491:14:491:14 | t | taint.cpp:491:14:491:14 | t | |
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| taint.cpp:491:14:491:14 | t | taint.cpp:491:14:491:14 | t | |
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| taint.cpp:491:14:491:14 | t | taint.cpp:491:52:491:52 | t | |
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| taint.cpp:491:14:491:14 | t | taint.cpp:491:52:491:52 | t | |
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| taint.cpp:501:3:501:7 | this | taint.cpp:501:25:501:28 | this | |
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| taint.cpp:501:17:501:20 | that | taint.cpp:501:17:501:20 | that | |
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| taint.cpp:501:17:501:20 | that | taint.cpp:501:30:501:33 | that | |
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| taint.cpp:501:30:501:33 | ref arg that | taint.cpp:501:17:501:20 | that | |
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| taint.cpp:502:3:502:7 | this | taint.cpp:502:30:502:44 | constructor init of field data [pre-this] | |
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| taint.cpp:502:22:502:25 | that | taint.cpp:502:35:502:38 | that | |
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| taint.cpp:502:40:502:43 | data | taint.cpp:502:30:502:44 | constructor init of field data | TAINT |
@@ -698,3 +706,13 @@
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| taint.cpp:563:6:563:14 | ref arg call to move | taint.cpp:563:16:563:16 | x [inner post update] | |
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| taint.cpp:563:6:563:14 | ref arg call to move | taint.cpp:566:7:566:7 | x | |
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| taint.cpp:563:16:563:16 | x | taint.cpp:563:6:563:14 | call to move | |
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| taint.cpp:571:20:571:28 | move_from | taint.cpp:572:2:572:10 | move_from | |
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| taint.cpp:571:20:571:28 | move_from | taint.cpp:574:7:574:15 | move_from | |
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| taint.cpp:571:20:571:28 | move_from | taint.cpp:576:38:576:46 | move_from | |
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| taint.cpp:572:2:572:10 | move_from [post update] | taint.cpp:574:7:574:15 | move_from | |
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| taint.cpp:572:2:572:10 | move_from [post update] | taint.cpp:576:38:576:46 | move_from | |
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| taint.cpp:572:2:572:26 | ... = ... | taint.cpp:574:17:574:20 | data | |
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| taint.cpp:572:19:572:24 | call to source | taint.cpp:572:2:572:26 | ... = ... | |
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| taint.cpp:576:28:576:36 | ref arg call to move | taint.cpp:576:38:576:46 | move_from [inner post update] | |
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| taint.cpp:576:28:576:48 | call to Class | taint.cpp:578:7:578:13 | move_to | |
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| taint.cpp:576:38:576:46 | move_from | taint.cpp:576:28:576:36 | call to move | |

‎cpp/ql/test/library-tests/dataflow/taint-tests/taint.cpp

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@@ -488,7 +488,7 @@ void test_getdelim(FILE* source1) {
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namespace std
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{
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template <class T>
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T &&move(T &t) noexcept; // simplified signature
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T &&move(T &t) noexcept { return static_cast<T&&>(t); } // simplified signature (and implementation)
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}
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namespace IntWrapper
@@ -498,7 +498,7 @@ namespace IntWrapper
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int data;
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Class() = default;
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Class(Class&&) = default;
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Class(Class&& that) { swap(that); }
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Class(const Class &that) : data(that.data) {}
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Class &operator=(const Class &that)
@@ -565,3 +565,15 @@ void test_move_assignment_operator()
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sink(y.data); // tainted [FALSE NEGATIVE in IR]
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sink(x.data); // tainted
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}
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void test_move_constructor()
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{
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IntWrapper::Class move_from;
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move_from.data = source();
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sink(move_from.data); // tainted
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IntWrapper::Class move_to(std::move(move_from));
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sink(move_to.data); // tainted [FALSE NEGATIVE in IR]
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}

‎cpp/ql/test/library-tests/dataflow/taint-tests/taint.expected

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@@ -81,3 +81,6 @@
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| taint.cpp:565:9:565:12 | data | taint.cpp:556:20:556:20 | x |
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| taint.cpp:565:9:565:12 | data | taint.cpp:558:11:558:16 | call to source |
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| taint.cpp:566:9:566:12 | data | taint.cpp:558:11:558:16 | call to source |
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| taint.cpp:574:17:574:20 | data | taint.cpp:572:19:572:24 | call to source |
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| taint.cpp:578:15:578:18 | data | taint.cpp:571:20:571:28 | move_from |
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| taint.cpp:578:15:578:18 | data | taint.cpp:572:19:572:24 | call to source |

‎cpp/ql/test/library-tests/dataflow/taint-tests/test_diff.expected

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@@ -49,3 +49,5 @@
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| taint.cpp:551:10:551:13 | taint.cpp:544:24:544:25 | AST only |
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| taint.cpp:565:9:565:12 | taint.cpp:556:20:556:20 | AST only |
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| taint.cpp:565:9:565:12 | taint.cpp:558:11:558:16 | AST only |
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| taint.cpp:578:15:578:18 | taint.cpp:571:20:571:28 | AST only |
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| taint.cpp:578:15:578:18 | taint.cpp:572:19:572:24 | AST only |

‎cpp/ql/test/library-tests/dataflow/taint-tests/test_ir.expected

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@@ -44,3 +44,4 @@
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| taint.cpp:551:10:551:13 | data | taint.cpp:545:12:545:17 | call to source |
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| taint.cpp:560:9:560:12 | data | taint.cpp:558:11:558:16 | call to source |
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| taint.cpp:566:9:566:12 | data | taint.cpp:558:11:558:16 | call to source |
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| taint.cpp:574:17:574:20 | data | taint.cpp:572:19:572:24 | call to source |

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