Add new clang-tidy check that finds uses of `std::lock_guard` and suggests
replacing them with C++17's more flexible and safer alternative
`std::scoped_lock`.
Here is a small description of how it works for better understanding of
the code:
Two separate AST matchers are registered:
- The first one matches declarations of `std::lock_guard` that are
single in their scope (only one `std::lock_guard` in `CompoundStmt`).
It's an easy case, we can emit warning right away.
- The second one matches `CompoundStmt`'s that have multiple
`std::lock_guard` declarations, which means that we may have consecutive
declarations of `std::lock_guard` that can be replaced by a single
`std::scoped_lock`. In order to ensure that declarations are
consecutive, we need to loop over `Stmt`'s in `CompoundStmt`. Here is a
small example:
```cpp
{
std::mutex m1, m2;
std::lock(m1, m2);
std::lock_guard<std::mutex> l1(m, std::adopt_lock); // first declaration of 'std::lock_guard'
std::lock_guard<std::mutex> l2(m, std::adopt_lock); // second declaration of 'std::lock_guard' that can be merged with first using 'scoped_lock'
}
```
This PR closes https://github.com/llvm/llvm-project/issues/107839.
In PR #128503, the CLI option would take precedence over the config option
only if it was set to `never`. This commit ensures the CLI option always takes
precedence over the config option.
ArrayRef has a constructor that accepts std::nullopt. This
constructor dates back to the days when we still had llvm::Optional.
Since the use of std::nullopt outside the context of std::optional is
kind of abuse and not intuitive to new comers, I would like to move
away from the constructor and eventually remove it.
This patch replaces std::nullopt with {}.
This patch fixes:
clang-tools-extra/clang-tidy/bugprone/SizeofExpressionCheck.cpp:371:26:
error: variable 'E' set but not used
[-Werror,-Wunused-but-set-variable]
The sizeof operator misuses in loop conditionals can be a source of
bugs. The common misuse is attempting to retrieve the number of elements
in the array by using the sizeof expression and forgetting to divide the
value by the sizeof the array elements. This results in an incorrect
computation of the array length and requires a warning from the sizeof
checker.
Example:
```
int array[20];
void test_for_loop() {
// Needs warning.
for(int i = 0; i < sizeof(array); i++) {
array[i] = i;
}
}
void test_while_loop() {
int count = 0;
// Needs warning.
while(count < sizeof(array)) {
array[count] = 0;
count = count + 2;
}
}
```
rdar://151403083
---------
Co-authored-by: MalavikaSamak <malavika2@apple.com>
Add checks to prevent rewriting when doing so might result in incorrect
code. The following cases are checked:
- There are multiple field declarations in one statement like `int a, b`
- Multiple fields are created from a single macro expansion
- Preprocessor directives are present in the struct
The adds a check that replaces specific numeric literals like `32767`
with the equivalent call to `std::numeric_limits` (such as
`std::numeric_limits<int16_t>::max())`.
Partially addresses #34434, but notably does not handle cases listed in
the title post such as `~0` and `-1`.
Add support for documenting concepts. This handles concepts and constraints on function and class templates.
Atomic constraints are not considered yet. We don't order constraints based on their conjunctive or disjunctive properties.
Summary:
Replacing by-value parameters with passing by-reference is not safe for
coroutines because the caller may be executed in parallel with the
callee, which increases the chances of resulting in dangling references
and hard-to-find crashes. See for the reference
[cppcoreguidelines-avoid-reference-coroutine-parameters](https://clang.llvm.org/extra/clang-tidy/checks/cppcoreguidelines/avoid-reference-coroutine-parameters.html).
Test Plan: check-clang-tools
LLVM style prefers no default label on fully covered switches to warn if
new enums are added. This patch removes the default label for that
purpose or uses IT_default instead of default if that was the only enum
not covered.
Run misc-use-internal-linkage check over clang-tidy code.
Also fixed a couple of other clang-tidy warnings.
Apart from issues in header files, all '.cpp' in
`clang-tools-extra/clang-tidy` must be clang-tidy clear now.
Adds a JSON generator backend to emit mapped information as JSON. This will enable a better testing format for upcoming changes. It can also potentially serve to feed our other backend generators in the future, like Mustache which already serializes information to JSON before emitting as HTML.
This patch contains functionality to emit classes and provides most of the basis of the generator.
Aims to fix#127471
Covered the edge case where an int expression is not necessarily
directly wrapped around an 'ImplicitCastExpr' which seemed to be a
requirement in 'use-integer-sign-comparison.cpp' check to trigger.
**For instance**:
```cpp
#include <vector>
bool f() {
std::vector<int> v;
unsigned int i = 0;
return i >= v.size();
}
```
New option AllowNoNamespaceComments for
`google-readability-namespace-comments.AllowNoNamespaceComments` is
added.
When true, the check will allow that no namespace comment is present. If
a namespace comment is added but it is not matching, the check will
fail. Default is `false`
Fixes#124264
Add check for `DeclRefExpr` which points to an explicit object
parameter.
Fixes#141381.
---------
Co-authored-by: fubowen <fubowen@protomail.com>
Co-authored-by: flovent <flbven@protomail.com>
Sometimes a project may want to enable this check only in C++, and
disable it in C, since the patterns the check warns about are quite
common and idiomatic in C, and there are no better alternatives.
Fixes#140659
Co-authored-by: Carlos Gálvez <carlos.galvez@zenseact.com>
