Is not allowed to define a type in an alias template definition.
This code:
template<int N>
using A1 = struct B1 { static auto constexpr value = N; };
A1<0> a1;
produces this output:
2: } ;
3: struct B1 { static const auto value = 0 a1 ;
test.cpp:2:57: error: Analysis failed. If the code is valid then please
report this failure. [cppcheckError]
using A1 = struct B1 { static auto constexpr value = N; };
^
because it tries to instantiate the invalid alias template definition
and generates garbage code.
This will now warn when doing something like this:
```cpp
template <class T, class K, class V>
const V& get_default(const T& t, const K& k, const V& v) {
auto it = t.find(k);
if (it == t.end()) return v;
return it->second;
}
const int& bar(const std::unordered_map<int, int>& m, int k) {
auto x = 0;
return get_default(m, k, x);
}
```
The lifetime warning is considered inconclusive in this case.
I also updated valueflow to no tinject inconclusive values unless `--inconclusive` flag is passed. This creates some false negatives because library functions are not configured to not modify their input parameters, and there are some checks that do not check if the value is inconclusive or not.
* make ellipsis ... a single token
Using cppcheck -E to preprocess code with ellipsis produces output that
can't be compiled because ... is split into 3 tokens.
* try to fix addon
This fixes the issue by making `ProgramMemory` keep track of values based on the conditions.
It also removes the `deadpointer` check since it duplicates the `invalidLifetime` check.
* Fix issue 8897: Huge array initializations
iscpp11init would take a lot of time when parsing huge arrays.
This patch add memoization to keeps track that we are parsing an array,
and allows to propagate the result without re-parsing the array for each
of its members.
* Use enum class instead of enum
* Try harder to track ref lifetimes
* Dont add lifetimes for references
* Use correct token
* Check for front and back as well
* Improve handling of addresses
* Formatting
* Fix FP
* Add missing Qt macros
Add two Qt macros that were missing
* Fix issue with __declspec and final
This change is a bit naive but it fixes the issues I was having when combining __declspec(dllexport) and final classes. Without the fix I get errors along the line of "The code 'class x final :' is not handled. You can use -I or --include to add handling of this code. "
There seems to be no reason for stopping checking the scope if a call to
free() is seen (or fclose() or realloc()), so just continue checking.
Also, if there are multiple arguments, check all, perhaps there are more
memory leaks to warn about.
This fixes the FP in cases like this:
```cpp
void f() {
bool b;
bool * x = &b;
if (x != nullptr)
x = 1;
}
```
It tracks the indirection of the uninit value in valueflow.
Use the AST a little bit more to improve the check. In order to do so,
rewrite the check to work from the outer function first and then check
the arguments, instead of the other way around.
It also fixes Trac ticket #9252, no warning is now given for
void* malloc1() {
return(malloc1(1));
}
This FP seems to be common in daca results.
It also makes it possible to improve handling of casts, for example
cppcheck now warns about
void f() {
strcpy(a, (void*) strdup(p));
}
But not for
char* f() {
char* ret = (char*)strcpy(malloc(10), "abc");
return ret;
}
These FP/FN were introduced when the check was switched to use the
simplified token list.
* dmake: Refactor object files to separate function
No functional change.
* dmake: Use range for loops
No functional change.
* Add all external cpp files instead of open coding
No functional change.
* Remove duplicate check.h in lib.pri HEADERS
* Add missing newline
No functional change, but the readability of the generated Makefile is
slightly improved.
This fixes false positives from daca@home where freopen is used to
reopen a standard stream. There is no longer a warning for
void f() {
assert(freopen("/dev/null", "r", stdin));
}
* template simplifier: refactor TemplateSimplifier::TokenAndName into a class
assert when more than one family flag is set
* fix function parameter names
* Fix for too much information in scope name
When the scope calculation encounters code such as
"friend class X::Y;"
or
"template<> class X<void> {"
it will now reset the additional name component of the scope that is about to be opened.
* Made sure new scope name is reset after being used
* Removed redundant scope calculation
* Add scope propagation code to insertToken
* Add relevant scope code to Token class
* Add code to calculate the scope of Tokens
* Add calculateScopes method to class
* Add missing include for shared_ptr
Since the number of test files is larger than the number of lib files,
this only caused an extra harmless '\' being printed after the last
header file in lib.pri. If the number of test files would have been
smaller than the number of lib files, the generated lib.pri would have
been broken.
* Fix#9225 (Crash on valid C++14 code)
This only fixes the crash. Specialization of nested templates is still
broken.
* fix cppcheck warnings
* fixed another cppcheck warning
* Use library for memleak checks
Change memleakOnRealloc and leakReturnValNotUsed to use library
configuration instead of hardcoding "realloc".
In order to do so, some care needs to be taken when matching for a
reallocation function, since it can no longer be assumed that the input
to be allocated is the first argument of the function. This complicates
getReallocationType() and checkReallocUsage() but is necessary in order
to handle for example freopen() properly.
Also, refactor memleakOnRealloc check to reduce duplicated code when
checking "a" and "*a". When doing so, extending the check to look for
arbitrary number of "*" can be done for free (just change an if
statement to a while statement). Most likely, this is an unusual case in
real world code.
* Remove redundant whitespace in Token::Match()
* Run on simplified checks
* Fix cppcheck warning
* Fix FP memory leak with unknown function call in condition
This was introduced in 8513fb81d2 when
fixing memory leaks for global variables allocated in condition. The
refactored code had an inconsistency where c and c++ code behaved
slightly differently when `var` is NULL. This seemed to not have an
impact as the code was written prior to 8513fb81d2,
but when the same code was used for conditions, FPs were introduced.
The introduced FPs were memleak warnings when there should have been an
information message about missing configurations for code like
void f() {
char *p = malloc(10);
if (set_data(p)) {}
}
Fix this by always returning true if varTok->Variable() is NULL for
both c and c++ code.
* Improve function name
This will diagnose more issues such as:
```cpp
void f(std::vector<int> &v) {
auto v0 = v.begin();
v.push_back(123);
std::cout << *v0 << std::endl;
}
```
* Fix adding unescaped slash token when splitting gcc case range.
Construction like case '!'...'~' converted to a list of separate case
tokens. When slas '\' symbol appears as a part of this list it was added
"as is", but it should be escaped like '\\' to be valid c++ code.
* Add test for switch-case range with slash
* Fix#9097 (Crash on thousands of "else ifs"s in gcc-avr package)
* increase recursion count maximum to 512 because cppcheck was hitting the 256 limit
* 512 was too much for windows
* Refactor Tokenizer::simplifyUsing to use continue to reduce indentation
added function findTemplateDeclarationEnd to skip template declarations
to reduce duplicate code
* fix travis build
This switches to use lifetime analysis to check for assigning to non-local variables:
```cpp
class test
{
public:
void f()
{
int x;
this->ptr = &x;
}
protected:
int *ptr;
};
```
* Partial fix for #9191 (simplifyTypedef: Problem when namespace is used)
This fixes simplifyUsing which has the same problem as simplifyTypedef.
simplifyUsing was designed to support using namespace but it was never
implemented. The changes are minor to add it.
simplifyTypedef requires much more work to support using namespace.
* reduce scope of variable
* make idx const
* Allow to configure realloc like functions
* memleakonrealloc: Bring back tests.
The old memleak checker was removed, and the tests for it was removed in
commit 9765a2dfab. This also removed the
tests for memleakOnRealloc. Bring back those tests, somewhat modified
since the checker no longer checks for memory leaks.
* Add realloc to mem leak check
* Add tests of realloc buffer size
* Configure realloc functions
* Add test of freopen
* Allow to configure which element is realloc argument
* Fix wrong close in test
cppcheck now warns for this
* Update manual
* Update docs
* Rename alloc/dalloc/realloc functions
Naming the member function realloc caused problems on appveyor. Rename
the alloc and dealloc functions as well for consistency.
* Change comparisson order
* Remove variable and use function call directly
* Create temporary variable to simplify
* Throw mismatchError on mismatching allocation/reallocation
* Refactor to separate function
* Fix potential nullptr dereference
As pointed out by cppcheck.
* Overlapping sprintf, improve handling of casts
If there is a cast of the argument buffer, cppcheck would print out the
expression including the cast, which looks a bit strange to talk about
Variable (char*)buf is used as...
Instead, only print the variable name without the cast.
Also, handle arbitrary many casts (the previous code only handled one).
Multiple casts of the input arguments is probably an unusual case in
real code, but can perhaps occur if macros are used.
* Fix printing of variable
... and add a test.
* Simplify testcase
* Update symbol database such that the override keyword implies that the function is also virtual
* Add test case for implicit override
* change isVirtual to hasVirtualSpecifier
* fix method documentation for getVirtualFunctionCalls and getFirstVirtualFunctionCallStack
* Fix isImplicitlyVirtual to consider the override keyword and document logic
* Fix getFirstVirtualFunctionCallStack and getVirtualFunctionCalls to use isImplicitlyVirtual instead of isVirtual so new test case passes
* Fix#9047 (c-style casts before malloc)
Note that there are still no warnings for c++-style casts
* Fix memleak check with casts of assignments in if-statements
* Fix possible null pointer dereference
As pointed out by cppcheck.
* Add check of astOperand2 when removing casts
This is similar to how it is done in other checks.
Sources were built with Clang but with increased verbosity of error detection.
A number of syntax and semantic warnings were encountered. Commit adds
changes to correct these warnings.
Some changes involve removing extra, and unncessary, semi-colons at EOL
(e.g. at end of switch clause).
Project astyle settings are not currently setup to detect if a file is to
have an extra carriage return after the last line of data. Two files were
altered to ensure an extra carriage return.
An advisory to enhance code was encountered in triage code. Clang advisory
on a for-loop interation value suggested that:
`use reference type 'const QString &' to prevent copying`
Building with enhanced clang warnings indicated a large number of
instances with the warning:
`warning: zero as null pointer constant`
Recommended practice in C++11 is to use `nullptr` as value for
a NULL or empty pointer value. All instances where this warning
was encountered were corrected in this commit.
Where warning was encountered in dependency code (i.e. external library)
no chnages were made. Patching will be offered upstream.
Increasing the verbosity in Clang, warnings were produced that identified
differences in code and doxygen-formatted comments.
Corrections applied to silence warnings yet still convey intent of original comments.
* Added scopeinfo member to token class
Moved ScopeInfo2 declaration here as well because that's where it needs to be now.
* Added scopeinfo accessors and declaration to class
* Add new method for calculating scopes
This replaces the methods in the TemplateSimplifier which calculate the current scope as the token list is iterated. The old method required checking if the scope had changed for every token multiple times (for multiple iterations), which was surprisingly costly. Calculating scopes in advance like this decreases runtime on a worst-case file by around thirty percent.
ScopeInfo objects are disposed of when the TemplateSimplification is done as they are not used later.
* Add calculateScopes method to header
* Removed code that calculated current scope
This has been replaced by code that calculates the scopes up front and stores them with each token, which is much faster.
* Fixed compile errors from extra parentheses
* Added missing code to fix memory leak
* Added code to actually clean up ScopeInfo structs
* Tidy up a dodgy for loop
* Convert argument to const ref
* Calculate missing scopes
As the templatesimplificator expands templates and does multiple passes it needs to make sure all scopes are calculated.
* Remove copying the scope to the next token
This is now done properly when scopes are calculated.
* Remove call to calculateScopes
This is now done by the TemplateSimplifier.
* Recalculate scopes for every pass of simplifyTemplates
* Add code to calculate extra scopes as they are added
I thought that this might be useful for calculating scopes when Tokens are created, but as there are several ways of creating Tokens that don't guarantee that they are placed in a list it is easier to just calculate scopes when you know you have a list and when you know you're adding to a list.
* Fix several bugs and poorly designed code
Remove the global scopes collection, and clean them up instead by iterating through the tokenlist to find them. This means scopes can be calculated by functions in the Token class as well as in the Tokenizer class without leaking the scope object.
Fix a couple of bugs in the calculateScopes method and make it more efficient.
* Remove unnecessary calls to calculateScopes
* Move brace to correct position
Calculating scopes during insertToken only needs to happen if we created a new Token.
* Handle 'using namespace' declarations separately
This fixes a bug caused by a statement matching 'struct B < 0 > ;'
* Fix argument name mismatch
* Actually use newScopeInfo when inserting Token
* Switch to using shared_ptr to hold scopeInfos
This means ScopeInfo2 objects get properly cleaned up when they are no longer needed.
* Change ScopeInfo member to be a shared_ptr
* Update code to use shared_ptr
* Add missing include for shared_ptr
* Remove unnecessary cleanup code
This has been replaced by shared_ptr for ScopeInfo2 objects
* fix adding instantiation of first argument to an instantiation
* add support for function pointer template variables
* fix more cases where templates ending in ">>" are changed to end in "> >"
* fix travis build
* standard types can't be a template parameter name
* remove redundant level == 0 checks
* fix lambda in template variable
* fix a test
* lib: isNonBoolStdType no longer needed
lib/checkbool.cpp:50:13: warning: unused function 'isNonBoolStdType'
[-Wunused-function]
static bool isNonBoolStdType(const Variable* var)
* cmake: C++11 is required
also change instructions to a more common syntax
This reverts commit 2a4be5ae1c.
When I look at daca@home now there are still lots of false negatives. So this bailout did not cause as much false negatives as I thought.
strdup() allocates the string length plus one for a terminating null
character. Add one to compensate for this.
Fixes false positive buffer out of bounds on code like this:
void f() {
const char *a = "abcd";
char * b = strdup(a);
printf("%c", b[4]); // prints the terminating null character
free(b);
}
Also, add a testcase for valueFlowDynamicBufferSize() and add tests for
strdup(), malloc() and calloc().
* Add non const version of some methods of Token
The aim is to reduce the (ab)use of const_cast.
* Cleanup some more const_cast in valueflow
* Remove useless const_cast
* Remove some const_cast from templatesimplifier
* Remove some const_cast from valueflow
* template simplifier: add 2 new template parameter simplifications
int{} -> 0
decltype(int{}) -> int
This fixes reduced test cases like #9153. I'm not sure they will help
real world code that much.
It was necessary to increase the pass count to 4 to get #9153 completly
simplified.
* relax decltype(type{}) simplification to any type
* Add cmd parameter for choosing between C90 and C99
Misra specifies different requirements to the uniqueness of
macros/enums/variables depending on what C standard
that's being used.
* Add standards configuration to each dump file
Read standards config from misra addon to decide what rules to use.
* Posix as standard setting should be deprecated. Don't include this in the xml
* Rewritten to use a switch
Refactored simplifyTemplateAliases to iterate over template type aliases
rather than instantiations. This fixed template type aliases that were
not templates.
Don't instantiate templates in template type aliases. They will get
instantiated once the type alias is instantiated. This required
increasing the template simplifier pass count to 3 so one of the
existing tests continued to work.
Specialized member classes declared outsize the class were not
recognized. This caused the the member class to be instantiated rather
than the specialized class. We already had a test for this but it was
wrong so it went unnoticed.
With the following code
int f(int x, int y) {
if (!!(x != 0)) {
return y/x;
}
cppcheck would wrongly warn that there might be a division by zero in
"return y/x;".
This improves the performance of the templatesimplefier by caching the template name position. I am not sure if the works entirely correctly but all the tests do pass with this change. Running this with gtest headers without removing unused template headers the time went from 48s to 5s, almost a 10x improvement.
* template simplifier: fix instantiation of variadic template with no arguments
* fix white space change
* add support for <class...>
* add variadic template flag
* Fix issue 8890: AST broken calling member function from templated base class
* Format
* Check for double bracket
* Add test to createLinks2
* Remove extra test
* Reduce test case for links
* build: remove -Wabi and add -Wundef
gcc >= 8 throws a warning about -Wabi (without a specific ABI version)
being ignored, while -Wundef seems more useful (as shown by the change
in config.h, which was probably an unfortunate typo)
travis.yaml should probably be updated soon, but was left out from this
change as the current images don't yet need it
* lib: unused function in valueflow
refactored out since 8c03be3212
lib/valueflow.cpp:3124:21: warning: unused function 'endTemplateArgument' [-Wunused-function]
* readme: include picojson
* make: also clean exe
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.
Daniel Marjamäki
IOBYTE
Paul Fultz II
warmsocks
Ken-Patrick Lehrmann
PKEuS
versat
Thomas Niederberger
Rikard Falkeborn
Armin Müller
amai2012
rebnridgway
orbitcowboy
Denis
Scott Furry
shaneasd
PKEuS
albert-github
Carlo Marcelo Arenas Belón
eivindt
adamjrichter
Nicodemes
Frank Zingsheim