Commit Graph

572 Commits

Author SHA1 Message Date
Paul Fultz II 3975913637 Extend lifetime checking for references
This will use the lifetime checker for dangling references. It will find these cases for indirectly assigned reference:

```cpp
int &foo()
{
    int s = 0;
    int& x = s;
    return x;
}
```

This will also fix issue 510 as well:

```cpp
int &f( int k )
{
    static int &r = k;
    return r;
}
```
2019-01-23 07:29:16 +01:00
Paul Fultz II 4b37f276c2 ValueFlow: Set arrays to true when converting to a boolean
This sets it by checking the parent. It doesn't handle function parameters yet.
2019-01-21 20:05:35 +01:00
Paul Fultz II 5fa956a597 Fix issue 8932: False positive knownConditionTrueFalse - valueflow ignores operator < (#1584) 2019-01-11 08:39:23 +01:00
practicalswift 0a1b3a9d6f Fix typos (#1568) 2019-01-06 17:15:57 +01:00
Daniel Marjamäki 5636497c0b Fixed #8863 (false positive: (warning) Accessing an item in container 's'. Either the condition 's.empty()' is redundant or 's' can be empty.) 2019-01-06 12:21:55 +01:00
Paul Fultz II bba6dfb8b2 Fix issue 4744: ValueFlow: known integer result
This fixes valueflow to have a value for `||` operator here:

```cpp
bool f()
{
	bool a = (4 == 3); // <-- 0
	bool b = (3 == 3); // <-- 1
	return a || b; // <-- 1
}
```
2019-01-03 07:05:31 +01:00
Daniel Marjamäki 2b63997c2c Fixed #8928 (false positive: (style) Variable 'x' is assigned a value that is never used.) 2019-01-02 20:23:02 +01:00
Daniel Marjamäki 39ceb53578 Comment out code in valueFlowArray. There was too many false positives. 2019-01-02 19:57:11 +01:00
Daniel Marjamäki 39a96a5a16 ValueFlow: Temporarily comment out valueFlowTerminatingCondition 2019-01-02 19:42:08 +01:00
Daniel Marjamäki 115be7dfc8 ValueFlow: better FwdAnalysis for complex expressions 2019-01-01 18:23:47 +01:00
Daniel Marjamäki be7afac875 ValueFlow: remove handling of == for complex expressions it did not work properly 2019-01-01 17:23:46 +01:00
Daniel Marjamäki 20436ea986 Fix compiler warning 2019-01-01 17:04:47 +01:00
rikardfalkeborn 13ffefc8b8 Valueflow: Fix right shift with more than 31 bits (#1553)
When comparing if the shift is large enough to make the result zero, use
an unsigned long long to make sure the result fits. Also, a check that
avoids setting the value if the shift is equal to or larger than the
number of bits in the operand (this is undefined behaviour). Finally,
add a check to make sure the calculated value is not too large to store.

Add test cases to cover this.

This was detected by an MSVC warning.

valueflow.cpp(1350): warning C4334: '<<' : result of 32-bit shift implicitly
                     converted to 64 bits (was 64-bit shift intended?)
2019-01-01 14:15:50 +01:00
Daniel Marjamäki ed514644b8 Renamed FwdAnalysisAllPaths to FwdAnalysis 2018-12-31 18:00:47 +01:00
Daniel Marjamäki 4918a18bfb ValueFlow: Value of expression after condition 2018-12-31 17:37:38 +01:00
Daniel Marjamäki 141ce7cd63 ValueFlow: Use FwdAnalysisAllPaths in ValueFlow to track complex expressions 2018-12-31 17:05:46 +01:00
Carlo Marcelo Arenas Belón 5ae6861a0f clang warnings (#1547)
* valueflow: remove unused variable known

since e4677ae640 will trigger :

lib/valueflow.cpp:506:20: warning: unused variable 'known' [-Wunused-variable]
        const bool known = (parent->astOperand1()->hasKnownValue() ||

* templatesimplifier: cleanup

since 48c960f56c showing:

lib/templatesimplifier.h:279:16: warning: private field 'mTokenizer' is not used
      [-Wunused-private-field]
    Tokenizer *mTokenizer;
2018-12-30 11:32:48 +01:00
Paul Fultz II e4677ae640 Fix issue 8910: Regression: ValueFlow: wrong conditional tokvalue
This fixes issue in:

```cpp
void f()
{
    char stack[512];
    RGNDATA *data;

    if (data_size > sizeof (stack))
        data = malloc (data_size);
    else
        data = (RGNDATA *)stack;

    if ((char *)data != stack)
            free (data); // <- data is not stack
}
```

It seems the `ProgramMemory` can't handle two known values(such as int and tok) together. So instead `ValueFlowAfterAssign` runs `ValueFlowForward` with tok values and then runs it with the other values.
2018-12-29 09:31:21 +01:00
rikardfalkeborn 036fcf7827 Fix warnings (#1541)
* Fix reorder warning

* Fix override warnings

Clang warns about missing overrides.

* Remove unused function

* Add missing argument to function calls
2018-12-28 12:59:05 +01:00
Daniel Marjamäki a40fe3c67f Fixed #7872 (ValueFlow: static_cast) 2018-12-27 21:33:01 +01:00
Daniel Marjamäki bc34f0239d Disable the subfunction value flow analysis. It does not work well and needs to be rewritten. There are false positives. 2018-12-18 14:36:49 +01:00
Paul Fultz II 34330b51d1 Fix issue 8905: Condition 'a==0' is always false
This fixes the FP in:

```cpp
void f(const int a[]){ if (a == 0){} }
```
2018-12-18 08:16:43 +01:00
Paul Fultz II 025881cf35 Fix issue 8829: Condition '...' is always true (int buf[42]; if(buf != NULL){})
This makes arrays non-null in valueflow, so it can catch comparisons against null that is always true:

```cpp
void f(void) {
   int buf[42];
   if( buf != 0) {;} // << always true
}
```
2018-12-17 06:07:34 +01:00
Paul Fultz II 3262a3bebe Add isSameExpression to valueflow analysis
Check for same expressions in valueflow analysis.
2018-12-16 07:35:27 +01:00
Paul Fultz II 45dcfad9f9 Fix issue 8899: False positive returnDanglingLifetime when returning by value
This fixes the FP from:

```cpp
#include <string>

class MyString
{
        public:
        MyString(char* source)
        {
                length = strlen( source );
                buffer = new char[length+1];
                if( buffer )
                {
                        strcpy( buffer, source );
                }
        }

        char* buffer;
        int length;
};

MyString Foo()
{
        char arr[20];
        sprintf(arr, "hello world");

        return arr;
}

void main()
{
        MyString str = Foo();

        printf(str.buffer);
}
```
2018-12-15 17:58:45 +01:00
Daniel Marjamäki 88c61e8d1e ValueFlow: Avoid FP when lambda is used 2018-12-04 18:54:26 +01:00
Daniel Marjamäki f5a94ed300 ValueFlow: Fix FP when lambda is called 2018-12-04 18:46:00 +01:00
Igor 61878c5e11 Add null pointer check to fix SEGFAULT (#1499)
* Add null pointer check to fix segfault

* Add first test case to reproduce problem
2018-12-02 14:36:01 +01:00
Paul Fultz II 3e1b34dd8f Fix FPs and crashes with byDerefCopy (#1503)
* Fix FP when inserting a range into a container

* Formatting

* Fix crash
2018-12-02 14:31:31 +01:00
Paul Fultz II b841b818d2 Fix 8872: Crash in LifetimeStore when there is no scope for variable
This fixes crash in:

```cpp
struct edit_line_paste_over {
    void operator()(agi::Context *c) override {
        paste_lines(c, true, [&](AssDialogue *new_line) -> AssDialogue * {
            AssDialogue *ret = paste_over(c->parent, pasteOverOptions, new_line, static_cast<AssDialogue*>(&*pos));
            return ret;
          });
    }
};
```
2018-12-01 19:11:26 +01:00
Paul Fultz II 67dd822910 Fix FP in lifetime anlaysis: Dont decay std array
This will fix FP with:

```cpp
std::array<char, 1> f() {
    std::array<char, 1> x;
    return x;
}
```
2018-12-01 19:09:19 +01:00
Daniel Marjamäki 0ad757fc78 valueFlowLifetime: Try to cleanup the loop a little. No functional change is intended. 2018-11-27 06:43:59 +01:00
Paul Fultz II 5a6f9ac82a Fix FP with strcmp and terminating conditions 2018-11-27 06:39:29 +01:00
Daniel Marjamäki 2887ee10c0 Fixed #8800 (Possible variable assignment ignored in boolean expression) 2018-11-26 14:00:03 +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 52f9650533 Refactoring: Use visitAstNodes 2018-11-23 19:16:19 +01:00
Daniel Marjamäki 745b58de26 Refactoring: Use visitAstNodes 2018-11-23 17:18:07 +01:00
Paul Fultz II f16d9d7d90 Issue 6175: Check lifetime of a variables stored in containers and member variables
Cppcheck will now warn for all cases here:

```cpp
#include <vector>
class CCluster {};
class MyClass
{ public:
    std::vector<CCluster*> m_cluster;
    void createCluster()
    {
        CCluster cl;
        CCluster* pcl=&cl;
        m_cluster.push_back(pcl);
    }
    void createCluster2()
    {
        CCluster cl;
        m_cluster.push_back(&cl);
    }
    CCluster* Cluster()
    {
        CCluster cl;
        CCluster* pcl=&cl;
        return pcl;
    }
    CCluster* Cluster2()
    {
        CCluster cl;
        return &cl;
    }
};

```
2018-11-21 08:43:57 +01:00
Daniel Marjamäki 9d8e5e36eb Added a few TODO comments 2018-11-20 22:57:01 +01:00
Paul Fultz II 7ef119cbfc Fix FPs in lifetime checker
This fixes several FPs in the lifetime checker. It also fixes issue [8846](https://trac.cppcheck.net/ticket/8846):

```cpp
int * f(int a[])
{
        return a;
}
```
2018-11-17 09:41:59 +01:00
Paul Fultz II d376e9f245 Track variable lifetime through function calls (#1481) 2018-11-16 06:12:28 +01:00
Daniel Marjamäki 39c04b650d astyle formatting
[ci skip]
2018-11-14 19:10:52 +01:00
Paul Fultz II 54453c5802 Fix FP when copying pointer to string (#1479) 2018-11-14 06:59:25 +01:00
Paul Fultz II f0c86b9d14 Fix issue 8842: Crash in valueFlowTerminatingCondition on incomplete code (#1480) 2018-11-14 06:23:45 +01:00
Daniel Marjamäki f096d7f474 astyle formatting
[ci skip]
2018-11-12 10:08:57 +01:00
Paul Fultz II 0e11bb07c8 Extend lifetime analysis to pointer usage (#1477)
* Use lifetime analysis for pointers as well

* Fix issue 1143: Pointer to local array

* Update message when using pointers

* Avoid infinite loop in tracing lifetimes
2018-11-12 10:08:17 +01:00
Daniel Marjamäki 717a2d370c astyle formatting
[ci skip]
2018-11-12 06:32:02 +01:00
Paul Fultz II 5bda102897 Fix warnings (#1476) 2018-11-12 06:08:57 +01:00
Paul Fultz II 68d6b96878 Diagnose invalid lifetimes (#1475)
* Add check for invalid lifetimes

* Fix FP with member variables

* Dont forward lifetime values in subfunction

* Update message to use out of scope
2018-11-11 16:43:54 +01:00
Daniel Marjamäki bdd4623124 valueFlowLibraryFunction: fix crash found with daca@home 2018-11-11 16:41:01 +01:00