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.