This uses the lifetime analysis to check when comparing pointer that point to different objects:
```cpp
int main(void)
{
int foo[10];
int bar[10];
int diff;
if(foo > bar) // Undefined Behavior
{
diff = 1;
}
return 0;
}
```
This will now warn for cases like this:
```cpp
auto& f() {
std::vector<int> x;
return x[0];
}
```
It also improves the handling of address of operator, so it can now warn across some function calls, like this:
```cpp
int& f(int& a) {
return a;
}
int* hello() {
int x = 0;
return &f(x);
}
```
Even if `ptr` is a local variable, the object `ptr->item` might be not.
So taking address of `ptr->item` is definitely not unsafe in general.
This commit fixes false positives triggered by commit
1.85-249-gf42648fe2 on the following code of sssd:
https://github.com/SSSD/sssd/blob/d409df33/src/sbus/request/sbus_request.c#L359
This reworks constStatement to find more issues. It catches issue [8827](https://trac.cppcheck.net/ticket/8827):
```cpp
extern void foo(int,const char*,int);
void f(int value)
{
foo(42,"test",42),(value&42);
}
```
It also catches from issue [8451](https://trac.cppcheck.net/ticket/8451):
```cpp
void f1(int x) {
1;
(1);
(char)1;
((char)1);
!x;
(!x);
~x;
}
```
And also:
```cpp
void f(int x) {
x;
}
```
The other examples are not caught due to incomplete AST.
Add a call to simplifyPlatformTypes() in
SymbolDatabase::setValueTypeInTokenList() to simplify return types of
library configured functions. This fixes the FN in #8141. Regression
tests are added, both for the original issue and another FN in the comments.
In order to do that, move simplifyPlatformTypes() to TokenList from Tokenizer.
This is a pure refactoring and does not change any behaviour. The code was
literally copy-pasted from one file to another and in two places
'list.front()' was changed to 'front()'.
When adding the call to simplifyPlatformTypes(), the original type of
v.size() where v is a container is changed from 'size_t' to 'std::size_t'.
Tests are updated accordingly. It can be noted that if v is declared as
'class fred : public std::vector<int> {} v', the original type of 'v.size()'
is still 'size_t' and not 'std::size_t'.
* Fixed#8962 ("(debug) Unknown type 'T'" with template typename parameter)
Only simple one parameter template functions with one function parameter
are supported.
* Added TODO test case for FIXME.
* Fixed#8971 ("(debug) Unknown type 'x'." using alias in class members)
* template simplifier: partial fix for #8972
Add support for multi-token default template parameters.
* template simplifier: fix for #8971
Remove typename outside of templates.
Qt defines `Q_NULLPTR` with `nullptr` if it is available, otherwise with `NULL`.
Since there seems to be no (sane) way to configure it the same way in the library configuration it is just defined with `NULL`.
* Fixed#8960 ("(debug) Unknown type 'x'." with alias in template class alias)
This commit adds non-template type alias support to the template
simplifier. Only relatively simple type aliases are supported at this
time. More complex types will be added later.
--debug-warnings will show unsupported type aliases.
Type alias support will be removed from the symbol database in the
future. Type alias tests have been removed from the symbol database
tests.
* Add the changes.
* Fix codacy warning.
* Fix travis warnings.
* template simplifier: fix crash on windows
Use right token when searching for template type alias to delete.
* template simplifier: fix a cppcheck warning
* Remove newlines after check(
* Remove unneeded statements after if-statements
As an example, the previous test case
check(
"bool foo(int x) {\n"
" if (x < 0)"
" return true;\n"
" return false;\n"
"}");
is changed to
check("void foo(int x) {\n"
" if (x < 0) {}\n"
"}");
This has basic handling of GUI projects. But further work will be needed to handle addons etc, the plan is that we will be able to run addons from the command line soon.
The unsigned less than zero checker looked for patterns like "<= 0".
Switching to use valueflow improves the checker in a few aspects.
First, it removes false positives where instead of 0, the code is using
0L, 0U, etc. Instead of having to hard code the different variants of 0,
valueflow handles this automatically. This fixes FPs on the form
uint32_t value = 0xFUL;
void f() {
if (value < 0u)
{
value = 0u;
}
}
where 0u was previously not recognized by the checker. This fixes#8836.
Morover, it makes it possible to handle templates properly. In commit
fa076598ad, all warnings inside templates
were made inconclusive, since the checker had no idea if "0" came from
a template parameter or not.
This makes it possible to not warn for the following case which was
reported as a FP in #3233
template<int n> void foo(unsigned int x) {
if (x <= n);
}
foo<0>();
but give a warning for the following case
template<int n> void foo(unsigned int x) {
if (x <= 0);
}
Previously, both these cases gave inconclusive warnings.
Finally, it makes it possible to give warnings for the following code:
void f(unsigned x) {
int y = 0;
if (x <= y) {}
}
Also, previously, the checker for unsigned variables larger than 0, the
checker used the string of the astoperand. This meant that for code like
the following:
void f(unsigned x, unsigned y) {
if (x -y >= 0) {}
}
cppcheck would output
[unsigned-expression-positive.c] (style) Unsigned variable '-' can't be negative so it is unnecessary to test it.
using expressionString() instead gives a better error message
[unsigned-expression-positive.c] (style) Unsigned expression 'x-z' can't be negative so it is unnecessary to test it.
Use `--check-library` for all tests as it was done before.
Re-enable all tests in runtests.sh again.
The regressions where runtests.sh would fail are disabled via "FIXME"
comment in the inline suppression comment.
* Add regression test for #6906
Ticket #6906 was fixed in f65cf220ba.
Add a test to make sure there are no regressions.
* Add regression test for #7284
Ticket #7284 was fixed in 5d1fdf7958.
Add tests to avoid regressions.
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;
}
```
As discussed in https://trac.cppcheck.net/ticket/8931 a regression test is added
to the test/cfg/runtests.sh script to make sure that unmatchedSuppression messages result in an Cppcheck exit code that signals a failure.
On linux systems (like travis) Qt often seems to be built with the option "reduce_relocations" which requires an application using it to specify the option "-fPIC".
* fix for CMake compile_commands.json input - director does not include trailing / which makes include directories wrong - so add it if it doesnt exist
* fix the bugfix for trailing / in the directory name of CMAKE JSON file, add also new test case to see if it works in both cases (with and without trailing /)
* revert adding accidental new line
To be able to use real Qt-Code in "test/cfg/qt.cpp" and still do a
syntax check the Qt settings are read out via pkg-config now if it is
available. This way the test now can contain Qt macros and functions and
the syntax check can still be used.
Additionally the same options as for the other tests are used now for
the Qt config tests.
Installing the package "qtbase5-dev" should be enough to enable the
syntax checks (already installed for travis tests).
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
}
```
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?)
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.
I sometimes find myself wondering which test cases I have broken when I fiddle with some check (since I then can try running these specific tests in the debugger, or make a small change and see if the tests pass). This PR adds the testclass and the test case names to the file and line number. I took special care to cover the case where an assert would be placed directly in the ```run()```-function, i.e., not inside a test case (from what I could see, no such case exists). If there is no need to handle this case, the code can be simplified (there wouldn't be need for the ```teardownTest()```-function for example).
The exact format for how to print the test name is very much up for discussion.
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
}
```
Add a check for function arguments that can be constant:
```cpp
extern void bar(int);
void f(int x) {
bar((x & 0x01) >> 7); // function 'bar' is always called with a '0'-argument
}
```
* Implement hexadecimal float conversion in MathLib::toDoubleNumber independent of C99/C++17
* Refactor MathLib::isFloatHex and cure some false results
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.
* Modify template simplifier to add forward declarations of some template functions so symbol database can make sense of the expanded templates.
* Fix travis.
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;
}
```
* 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
* 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
* 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
* Add check for return value of boolean function
The rule for converting an integer to a boolean is that 0 is mapped to
false and everything else is mapped to true. There is nothing wrong with
the following code (according to the standards):
bool f()
{
return -1;
}
and neither gcc nor clang will warn about it. However, it's a bit
confusing. This commit adds a check that warns when a value other than 0
or 1 is returned from a boolean function (similar to the existing check
that functions with boolean arguments are only passed 0 or 1). Since the
code is perfectly legal, set the severity to "Style".
* Use early continue and remove some braces
* Add testcase with multiple returns
* Avoid null pointer dereference in case of return without operand
* Skip lambdas
Add TODO-test cases that shows FPs when the return type of lambdas are
specified explicitly (this is a problem with findLambdaEndToken).
* Enable testcases
* findLambdaEndToken: Add tests
* Add handling of explicit return in findLambdaEndToken()
* Use AST in findLambdaEndToken()
* Fix ast when lambda is mutable
The checker does not care if it's a header or source file. So I guess these tests were added to test
some parsing problem. Nowadays, #line is removed by simplecpp::preprocess, but there is no proper
testing for it in simplecpp.. I will add some testing for #line asap.
It is possible to define default template parameter values in forward
declarations and not define any in the actual declaration. Cppcheck
ignores forward declarations and only uses the default values in the
actual declaration so default values in forward declarations are copied
to the actual declaration when necessary.
* insecureCmdLineArgs: Fixed FN in case strdup() copies argv[].
* Formatted the code. There are no functional changes intended.
* Changes due to review comments from Daniel.
* Identify return conditions in multiconditions
* Improve error messages
* Check return statements are always true or false
* Add more tests for FPs
* Fix FP when returning const like variables
* Fix FP when returning pointers or classes
* Fix FP with member variable access
* Check non-local variables
* Use simplematch
* Check for null
* 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
* Fix specialized template regression.
Only check for instantiation of template being processed rather than
count of all instantiations.
* Add 2 more tests.
* insecureCmdLineArgs: Fixed false negatives in case arguments are const.
* Formatted the code, there are functional changes.
* Simplified matching as suggested by Daniel.
* #4241: Check for address of single character passed as string
Add a check that address of a single character is not passed as argument
to argument marked as strings (using strz). The check does not warn if
the address of a character with known value '\0'.
Since ValueFlow currently does not handle global constants (see #7597),
do not warn if the variable is global to avoid FPs when the address of
a global variable assigned to '\0' is passed to a function expecting a
string.
Remove comment in docs saying strz is unused.
* Change asdf to Hello world
* Add test of address to first element in string
* Add error reporting function to getErrorMessages
* Fix strings in test
* Fixed#8693 (Template specialization: Constructor detected as normal function (functionStatic error))
Refactor template simplifier to remove the existing full specialization
function expandSpecialized and allow full specializations to use the
existing function expandTemplate. The function expandTemplate was
modified to either expand the template like it originally did by copying
it or to modify the template in place. Both instantiated and
uninstantiated full specializations are modified in place. This also
fixes#8692 and probably other related tickets as well.
The function simplifyTemplates now tries twice to simplify templates so
more templates can be simplified. We should try as many times as
necessary to find all possible templates. We can't do that now because
uninstantiated templates are left unchanged. It is relatively straight
forward to have the new code also expand in place uninstantiated
templates with their symbolic types but namespaces are not handled
properly (ticket #8671) and it would introduce regressions.
* Fix travis warnings.
The while part of a do-while loop looks almost like a function call, so
extend the check for function calls to ignore while-statements.
Note that there was only an FP when checking c-code, since the check is
disabled for c++-code. Therefore, make sure the test cases are run on a
c-file.
Daniel Marjamäki
Paul Fultz II
amai2012
orbitcowboy
versat
Kamil Dudka
rikardfalkeborn
IOBYTE
Simon Martin
Lauri Nurmi
juremenart
practicalswift
amai2012
Igor
Colomban Wendling
Carlo Marcelo Arenas Belon
orbitcowboy
PKEuS