Commit Graph

353 Commits

Author SHA1 Message Date
Paul Fultz II ba037837c9 Track lifetime across multiple returns
This will now warn when doing something like this:

```cpp
template <class T, class K, class V>
const V& get_default(const T& t, const K& k, const V& v) {
    auto it = t.find(k);
    if (it == t.end()) return v;
    return it->second;
}
const int& bar(const std::unordered_map<int, int>& m, int k) {
    auto x = 0;
    return get_default(m, k, x);
}
```

The lifetime warning is considered inconclusive in this case.

I also updated valueflow to no tinject inconclusive values unless `--inconclusive` flag is passed. This creates some false negatives because library functions are not configured to not modify their input parameters, and there are some checks that do not check if the value is inconclusive or not.
2019-09-11 19:25:09 +02:00
Paul Fultz II dc201d110d Fix issue 9274: false negative: (error) Buffer is accessed out of bounds (std::string, std::wstring) 2019-09-03 06:43:54 +02:00
Paul Fultz II 88d194214f Fix FP with invalidContainerRef (#2141) 2019-09-03 06:41:35 +02:00
Paul Fultz II cb509f1a8b Fix issue 4845: alias to vector element invalid after vector is changed (#2113)
* Try harder to track ref lifetimes

* Dont add lifetimes for references

* Use correct token

* Check for front and back as well

* Improve handling of addresses

* Formatting

* Fix FP
2019-09-02 06:58:09 +02:00
Paul Fultz II 121093658d Fix issue 9202: False positive: std::array, size is a constant (#2132) 2019-09-01 09:44:34 +02:00
Daniel Marjamäki 996daaee4e STL: Fixed outOfBounds false positive 2019-08-24 15:40:29 +02:00
Paul Fultz II ef714225bb Use library to track container lifetimes 2019-08-15 21:14:54 +02:00
Paul Fultz II 13df5b2413 Fix FP with negative index and negated condition (#2081) 2019-08-14 06:32:31 +02:00
Paul Fultz II c0c6f92221 Fix issue 8431 and 8776: Size of constant string
Fixes these cases:

```cpp
void f(void) {
        const std::string msg="xyz";
        if(!msg.empty()){} // Always true
}
```

And out of bounds access:

```cpp
#include <string>
char fstr1(){const std::string s = "<a><b>"; return s[42]; }
wchar_t fwstr1(){const std::wstring s = L"<a><b>"; return s[42]; }
```
2019-08-12 20:24:16 +02:00
Paul Fultz II 68e8253920 Fix issue 8313 and 7326: Track values of pointer aliases in valueflow 2019-08-12 12:58:53 +02:00
Paul Fultz II 3ec3bd52e0 Fix FP when using a pointer to a container (#2029) 2019-07-24 00:04:49 +02:00
Paul Fultz II a08a9c1349 Switch to use lifetime analysis for iterators and pointers to invalid containers
This will diagnose more issues such as:

```cpp
void f(std::vector<int> &v) {
    auto v0 = v.begin();
    v.push_back(123);
    std::cout << *v0 << std::endl;
}
```
2019-07-18 10:56:44 +02:00
Daniel Marjamäki 90a215af0e Rephraze performance message. /would be faster/could be faster/ to indicate that Cppcheck is not _sure_ that it would be faster 2019-07-17 16:06:10 +02:00
Daniel Marjamäki 4d9b1e6c3d Fixed #9094 (Tokenizer::createLinks2 problem with 'x%x<--a==x>x') 2019-05-11 19:11:40 +02:00
Daniel Marjamäki fe04c15c9e CheckStl: Modernize the recommendations. string::starts_with is more intuitive than string::compare 2019-05-05 10:35:44 +02:00
Paul Fultz II 091f4bcf8d Add check for unnecessary search before insertion
This will warn for cases where searching in an associative container happens before insertion, like this:

```cpp
void f1(std::set<unsigned>& s, unsigned x) {
    if (s.find(x) == s.end()) {
        s.insert(x);
    }
}

void f2(std::map<unsigned, unsigned>& m, unsigned x) {
    if (m.find(x) == m.end()) {
        m.emplace(x, 1);
    } else {
        m[x] = 1;
    }
}
```

In the case of the map it could be written as `m[x] = 1` as it will create the key if it doesnt exist, so the extra search is not necessary.

I have this marked as `performance` as it is mostly concerning performance, but there could be a copy-paste error possibly, although I dont think thats common.
2019-05-02 11:04:23 +02:00
Daniel Marjamäki 54bea2847a STL: Better out of bounds checking for empty containers when index is unknown 2019-03-29 15:20:17 +01:00
Daniel Marjamäki 3c30d274a0 Clarify STL out of bounds warning message 2019-03-29 11:13:25 +01:00
Daniel Marjamäki e88a0c00c1 Fixed #9039 (STL: array index out of bounds: str.begin() + 1) 2019-03-28 12:49:52 +01:00
Daniel Marjamäki 3dc34f1515 Disable all simplified checks 2019-03-16 09:17:50 +01:00
Daniel Marjamäki f9fe6cc96a STL: Removed auto_ptr checking. 2019-03-09 07:48:01 +01:00
Daniel Marjamäki 725abbfac3 Move CheckStl::missingComparison to normal checks 2019-03-08 20:19:40 +01:00
Daniel Marjamäki bd7790fd8c Update copyright year 2019-02-09 07:24:06 +01:00
Daniel Marjamäki 8dd641b8be Use OVERRIDE in test 2019-01-12 15:45:25 +01:00
Paul Fultz II be6782d386 Fix FP 8891: Incorrect return scope when using uniform initialization
This fixes the FP in:

```cpp

std::string f(const std::string& data)
{
  if (data.empty())
    return {};

  data[0];
}
```
2018-12-14 18:31:10 +01:00
Daniel Marjamäki dd94bfede9 CheckStl: Improving checking of container access out of bounds 2018-11-28 19:27:28 +01:00
Daniel Marjamäki 6493db6ca2 Try to clarify message for container access out of bounds a little more. 2018-11-28 13:58:01 +01:00
Daniel Marjamäki 0f2f807798 Improve the container out of bounds messages. They are still not perfect. 2018-11-28 07:03:56 +01:00
Paul Fultz II a3921ea861 Refactor valueFlowAfterCondition
So this unifies the `valueFlowAfterCondition` so it re-uses more code between checking for integers and container sizes. This should make valueFlowContainer more robust.

It also extends valueflow to support container comparisons such as `if (v.size() < 3)` or `if (v.size() > 3)` using the same mechanism that is used for integers.
2018-11-24 10:07:12 +01:00
Daniel Marjamäki 4983a6a5dc astyle formatting 2018-10-18 20:08:32 +02:00
Igor 0a9be3e734 Improve STL iterators checking (#1380)
* Improve STL interators checking

* Improve error messages for container iterators from different scopes

* Mini refactoring

* Replace hardcoded pattern to ValueType::Type::ITERATOR

* Error messages improvements, more tests and refactoring

* Refactoring after code review

* Put getting operand data into separate function

* Update getErrorMessages and iterator errors ids

* Refactoring

* Fix error

* Refactoring, early return implementation

* Delete redundant code

* Tiny changes in comments
2018-10-17 06:36:51 +02:00
Daniel Marjamäki 053b0d1654 STL: enable inconclusive warnings with --inconclusive 2018-10-09 20:10:43 +02:00
Paul Fultz II 4ed22f1ff8 Fix some FPs in mismatchingContainerExpression (#1402) 2018-09-30 14:49:58 +02:00
Paul Fultz II d43cd56afd Show line number when suggesting std::transform (#1385) 2018-09-21 10:38:30 +02:00
orbitcowboy a26ac4d266 Running astyle. There is no functional change intended. 2018-09-21 08:53:09 +02:00
Paul Fultz II 1e347f6cde Initial check for recommending algorithms (#1352)
Add initial check for loop algorithms
2018-09-19 18:58:59 +02:00
Paul Fultz II eb07280075 Fix issue 8743: FP when derefencing iterators (#1376) 2018-09-12 17:33:53 +02:00
Daniel Marjamäki 772939476d Remove inconclusive warnings about reading empty stl container. We have better ValueFlow-based checking. 2018-09-09 11:25:04 +02:00
Paul Fultz II f7e7e9bd3c Fix issue 8736: Iterators to containers from different expressions (a.begin().x == b.begin().x) (#1370) 2018-09-07 07:08:02 +02:00
Daniel Marjamäki 756c1d8de7 Fixed #8341 (error:iterators not correct) 2018-09-02 21:04:45 +02:00
Paul Fultz II f79849f6ba Diagnose mismatching iterators used together in operators (#1343)
* Diagnose mismatching iterators used together in operators

* Fix fp getting iterator expression in function call
2018-08-21 06:34:30 +02:00
Daniel Marjamäki 0e30bdef9d containerAccessOutOfBounds: Fix FPs for maps etc 2018-08-11 18:57:21 +02:00
Daniel Marjamäki 1f427eda8f CheckStl: rewrite and refactor out of bounds checker 2018-08-11 11:40:48 +02:00
Daniel Marjamäki 81f54f7094 Fixed #8681 (ValueFlow: Container size) 2018-08-10 11:29:16 +02:00
Paul Fultz II ed197f235a Fix issue 4693: Diagnostic when using the same iterators to an algorithm (#1326)
* Fix issue 4693: Diagnostic when using the same iterators to an algorithm

* Update classinfo
2018-08-05 09:10:54 +02:00
Paul Fultz II 0d35a96594 Improve checking of mismatch iterators (#1293) 2018-07-26 22:00:48 +02:00
Daniel Marjamäki b398398dec Fixed #8360 (false positive "Ineffective call of function 'empty()'") 2018-07-10 22:58:02 +02:00
IOBYTE ce50df8047 Fix override warnings. (#1234) 2018-05-15 16:37:40 +02:00
Daniel Marjamäki 8304290f06 astyle formatting
[ci skip]
2018-04-27 10:29:27 +02:00
amai2012 55983e2a0b #8509 Uniform initialization ignored for iterator 2018-04-26 08:57:25 +02:00