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
Fix some crashes caused by the template simplifier generating bad code
for some instantiations.
Sorry but there are no tests because I was unable to get C-Reduce to
create examples that were not garbage code.
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.
temp.bufferSizeArg2 was not initialized when only bufferSizeArg1
was specified or the value was out of range. But in valueflow.cpp in
valueFlowDynamicBufferSize() it was used as if it is always initialized
and has a sane value (greater than 0).
* Add defines set by compiler options when using compilation database
sets __cplusplus and __STDC_VERSION__ based on -std and the defines for -municode, -fpie, -fPIE, -fpic and -fPIC
* Fixed merge
This limits the recursion depth as a last line of defense to avoid stack
overflows when there are really huge arrays.
See https://trac.cppcheck.net/ticket/8922
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)
- CLI: Save the libraries that should be loaded to a list and load them
after the std.cfg has been loaded.
- GUI: Load std.cfg (and windows.cfg / posix.cfg when applicable) before
setting other options and loading the other libraries.
In the project-file-dialog the std.cfg is searched first. If some
other library fails to load is is retried with first loading std.cfg.
- boost.cfg: Enable containers that depend on std containers.
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.
CheckUninitVar::isMemberVariableAssignment uses argument direction
to check for assignment when the member variable is handed over to a
function by reference. Currently implemented for "in" direction. "out"
will be added with another commit.
lib/settings.cpp:53:7: warning: field 'removeUnusedIncludedTemplates' will be
initialized after field 'removeUnusedTemplates' [-Wreorder]
removeUnusedIncludedTemplates(false),
^
lib/settings.cpp:54:7: warning: field 'removeUnusedTemplates' will be
initialized after field 'checkConfiguration' [-Wreorder]
removeUnusedTemplates(false),
^
* 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.
This enhances the library configuration so the direction of function
arguments can be specified (in, out, inout).
isVariableChangedByFunctionCall() uses this information now to avoid
guessing.
If no 'alternatives' argument was specified and the `<warn/>` element
did not contain any text Cppcheck crashed because of a null pointer
access.
If there is no 'reason' and no 'alternatives argument and also no text loadFunction() returns with an error.
* 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.
otherwise showing (with Apple LLVM version 10.0.0):
lib/settings.cpp:34:7: warning: field 'jointSuppressionReport' will be
initialized after field 'maxCtuDepth' [-Wreorder]
jointSuppressionReport(false),
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