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.
A common pattern is to have a function like similar to this:
bool isFlagSet(uint32_t f) {
return f & 0x4;
}
Warning that the function returns a non-boolean in this case is too
noisy, it would be better suited for a Misra check, so remove the
warnings in the most obvious cases.
Change the astStringVerbose() recursion to extend a string instead of
returning one. This has the benefit that for tokens where the recursion
runs deep (typically large arrays), the time savings can be substantial
(see comments on benchmarks further down).
The reason is that previously, for each token, the astString of its
operands was constructed, and then appended to this tokens astString.
This led to a lot of unnecessary string copying (and with that
allocations). Instead, by passing the string by reference, the number
of temporary strings is greatly reduced.
Another way of seeing it is that previously, the string was constructed
from end to beginning, but now it is constructed from the beginning to
end. There was no notable speedup by preallocating the entire string
using string::reserve() (at least not on Linux).
To benchmark, the changes and master were tested on Linux using the
commands:
make
time cppcheck --debug --verbose $file >/dev/null
i.e., the cppcheck binary was compiled with the settings in the
Makefile. Printing the output to screen or file will of course take
longer time.
In Trac ticket #8355 which triggered this change, an example file from the
Wine repository was attached. Running the above cppcheck on master took
24 minutes and with the changes in this commmit, took 22 seconds.
Another test made was on lib/tokenlist.cpp in the cppcheck repo, which is
more "normal" file. On that file there was no measurable time difference.
A synthetic benchmark was generated to illustrate the effects on dumping
the ast for arrays of different sizes. The generate code looked as
follows:
const int array[] = {...};
with different number of elements. The results are as follows (times are
in seconds):
N master optimized
10 0.1 0.1
100 0.1 0.1
1000 2.8 0.7
2000 19 1.8
3000 53 3.8
5000 350 10
10000 3215 38
As we can see, for small arrays, there is no time difference, but for
large arrays the time savings are substantial.
Before this fix, the code:
```
class A {
A(int, int x=3){
x;
}
};
```
Was considered OK.
But explicit keyword is still needed
I'm still new to open-source contributions, so I will gladly take advice.
This fixes simplifyUsing to remove 'typename' and 'template' from type
aliases of the form: using T3 = typename T1::template T3<T2>;
This lets the template simplifier instantiate the type alias which will
then remove the using type alias.
The crash will still happen if there is no instantiation because the
type alias will not be removed. The type alias is what cppcheck is
crashing on after the template simplifier and that still needs fixing.
* Fixed#8889 (varid on function when using trailing return type.)
Don't set varid for trailing return type.
* Add a test for #9066 (Tokenizer::setVarId: varid set for trailing return type)
* Handle 'arguments' sections in compile_commands.json
Previous code assumes 'commands' exists and ill assert if t does not.
* Correct typo checking for "arguments" rather than "commands"
* Use ostringstring rather than stringstream
* Add test deominstrating graceful degradation
* Add test for parsing "arguments" rather than "commands"
This is trying to fix the issue by fixing the ast and symbol database. First, the ast nodes will be created for the init list and the symbol database will not mark it as a scope. I am not sure if this is the correct approach as I dont really understand how the AST part works.
It did change the AST for `try {} catch (...) {}` but that is because it incorrectly treats `try {}` as an initializer list.
Improve the internal check for redundant null pointer check before
calling Token::Match() (and friends). Now, warn about code snippets like
if (a && tok && Token::Match(tok, "foo"))
Also, extend the check for the inverted case.
There is still no warning for
if (tok && a && Token::Match(tok, "foo"))
since that would require checking if a is independent of tok.
* teststring.cpp: Fix ternary syntax in tests
* stringLiteralWrite: Add tests wide character and utf16 strings
* suspiciousStringCompare: Add test with wide character string
* strPlusChar: Handle wide characters
* incorrectStringCompare: Add test with wide string
* Suspicious string compare: suggest wcscmp for wide strings
* deadStrcmp: Extend to handle wide strings
* sprintfOverlappingData: Print name of strcmp function
* Conversion of char literal to boolean, add wide character tests
* Conversion of char literal to boolean, fix ternary
This only fixes the crash. It does not fix the underlying problem of
template using with templates of templates causing the use of deleted
instantiations.
This fixes issue 8996 by improving the alias checking by using lifetime analysis. It also extends the lifetime checker to handle constructors and initializer lists for containers and arrays.
Some POSIX and Windows functions require buffers of at least some
specific size. This is now possible to configure via for example this
minsize configuration: `<minsize type="value" value="26"/>`.
The range for valid buffer size values is 1 to LLONG_MAX
(9223372036854775807)
- Remove redundant function configurations for the same function since
it is not (yet) possible to configure overloaded functions. Instead mark
the optional arguments with `default="0"` so the configuration works
with a different number of arguments.
- Add documentation to boost.cfg (links and function declarations).
- Rearranged configurations so functions, defines, ... are together now.
- Add `direction` for function arguments where applicable.
- Add some tests to boost.cpp.
There are important TODOs still; for instance adding CTU support using our CTU infrastructure, add handling of pointers (maybe I'll use FwdAnalysis for this), add handling of multidimensional arrays, etc..
This handles concatenated strings and characters from simplecpp.
Previously, L'c' would be preprocessed to the tokens "L" and "'c'".
cppcheck would then remove the "L" token and set "'c'" to be a wide
character literal. Now, it needs to remove the prefix instead.
When doing this, add handling of utf32 encoded literals (U) and UTF-8
encoded literals (u8).
CheckUninitVar::isMemberVariableAssignment uses argument direction "out"
now also to check for assignment when the member variable is handed over
to a function by reference.
testuninitvar.cpp: Improve tests, use a test library configuration.
strcpy_s belongs to the standard so it must be in std.cfg instead of
windows.cfg.
Configuration for strcpy_s has been improved and tests were added.
Found by daca@home
* std.cfg: Add further argument directions (in, out, inout).
* testlibrary.cpp: Add test for function argument direction configuration.
* std.cfg: runastyle and add some more direction configurations.
* library.h: Add documentation for function argument direction enum.
* Do not use "direction" library information for pointer arguments.
Also fix further unmatched uninitvar messages in std configuration
tests.
* std.cfg: Add more argument direction configurations.
* test/cfg/std.c: Add test for argument direction configuration.
* astutils.cpp: Only ignore pointer arguments for out/inout arguments.
* library.h: Use suggested documentation for argument direction enum.
For now, only print the ways of running testrunner and the few options
that are available.
Also, refactor to remove an unneeded const_cast and use a range for loop.
Partially fixes#8514.
* template simplifier: make sure all instantiations are found and expanded in #5097
* template simplifier: check output on another test
* template simplifier: add output to another test
* template simplifier: instantiate template class when something inside class instantiated.
* template simplifier: add output to another test that now works
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).