Commit Graph

567 Commits

Author SHA1 Message Date
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
Paul Fultz II e46691597e Fix issue 8841: FP knownConditionTrueFalse - Dont treat unknown function as noreturn (#1474)
* Fix issue 8841: Dont treat unknown function as noreturn

* Add a parameter to set default value when the function is unknown
2018-11-11 08:04:01 +01:00
Daniel Marjamäki d5a478d5c5 astyle formatting
[ci skip]
2018-11-10 21:30:01 +01:00
Paul Fultz II 1ffcc6b730 Add initial lifetime checker (#1448)
* Inital valueflow lifetime checker

* Forward values

* Add initial tests

* Fix deplicate messages

* Fix traversing nested lambdas

* Turn test case into a todo

* Skip if returning a container

* Fix FP when using references

* Add missing header

* Fix FP from broken scopes

* Fix FP with static variable

* Add test for more FPs

* Parse lambda functions

* Check for capture by value

* Add tests for using a container and lambda together

* Fix cppcheck errors

* Add test for nextAfterAstRightmostLeaf

* Add valueflow tests

* Update error message

* Check for correct lambda token

* Improve error path reporting

* Fix hang when parsing arrays that look almlost like lambdas
2018-11-10 16:40:40 +01:00
Paul Fultz II 36e663e250 Fix issue 8839: FP knownConditionTrueFalse - condition inside a while-clause (#1469) 2018-11-09 06:09:51 +01:00
Paul Fultz II 7373be2bfa Add a pass in valueflow for terminating conditions (#1323)
* Add valueflow for terminating conditions

* Add valueflow test

* Dont check for same expressions for now to avoid double diagnostics

* Check nesting

* Add more tests

* Ensure conditions happen in order

* Check for null

* Add error path

* Support same expression check as well

* Use early continue

* Skip checking the same token

* Avoid double condtion diagnosis

* Fix FP when in switch statements

* Fix FP when time function

* Skip conditional escapes

* Use simpleMatch

* Fix naming

* Fix typo
2018-11-07 06:49:07 +01:00