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.
Add new check misc-use-internal-linkage to detect variable and function
can be marked as static.
---------
Co-authored-by: Danny Mösch <danny.moesch@icloud.com>
This check detects **hostile-RAII** objects which should not **persist
across a suspension point in a coroutine**.
Some objects require that they be destroyed on the same thread that
created them. Traditionally this requirement was often phrased as "must
be a local variable", under the assumption that local variables always
work this way. However this is incorrect with **C++20 coroutines**,
since an intervening `co_await` may cause the coroutine to suspend and
later be resumed on another thread.
The lifetime of an object that requires being destroyed on the same
thread must not encompass a `co_await` or `co_yield` point. If you
create/destroy an object, you must do so without allowing the coroutine
to suspend in the meantime.
The check considers the following type as hostile:
- **Scoped-lockable types**: A scoped-lockable object persisting across
a suspension point is problematic as the lock held by this object could
be unlocked by a different thread. This would be undefined behaviour.
- Types belonging to a configurable **denylist**.
```cpp
// Call some async API while holding a lock.
const my::MutexLock l(&mu_);
// Oops! The async Bar function may finish on a different
// thread from the one that created the MutexLock object and therefore called
// Mutex::Lock -- now Mutex::Unlock will be called on the wrong thread.
co_await Bar();
```
This patch connects the check for const-correctness with the new general
utility to add `const` to variables.
The code-transformation is only done, if the detected variable for const-ness
is not part of a group-declaration.
The check allows to control multiple facets of adding `const`, e.g. if pointers themself should be
marked as `const` if they are not changed.
Reviewed By: njames93
Differential Revision: https://reviews.llvm.org/D54943
This reverts commit b94db7ed7eaf4a3b21f600653a09c55cab77b79f.
See comments on https://reviews.llvm.org/D112916:
- breaks `check-clangd`, and makes clang-tidy crash on simple inputs
- likely does the wrong thing in cross builds
Also revert follow-up "[gn build] (manually) port b94db7ed7eaf (Confusables.inc)"
This reverts commit 180bae08a04d4dc724cb5e6f2ea9df8641a3f657.
Detect when an identifier contains some Right-To-Left characters.
This pass relates to https://trojansource.codes/
Example of misleading source:
short int א = (short int)0;
short int ג = (short int)12345;
int main() {
int א = ג; // a local variable, set to zero?
printf("ג is %d\n", ג);
printf("א is %d\n", א);
}
This is a recommit of 299aa4dfa1d8c120648b1404b481d858b76c8173 with missing
option registration fixed.
Differential Revision: https://reviews.llvm.org/D112914
This reverts commit 7f92a1a84b96ff0b7568a35704c9483e9f24f057.
It triggers an assert, see http://45.33.8.238/linux/60293/step_9.txt
"AST/Decl.h:277: llvm::StringRef clang::NamedDecl::getName() const: Assertion `Name.isIdentifier() && "Name is not a simple identifier"' failed."
Detect when an identifier contains some Right-To-Left characters.
This pass relates to https://trojansource.codes/
This is a recommit of 299aa4dfa1d8c120648b1404b481d858b76c8173 with missing
option registration fixed.
Differential Revision: https://reviews.llvm.org/D112914
Summary:
Recursion is a powerful tool, but like any tool
without care it can be dangerous. For example,
if the recursion is unbounded, you will
eventually run out of stack and crash.
You can of course track the recursion depth
but if it is hardcoded, there can always be some
other environment when that depth is too large,
so said magic number would need to be env-dependent.
But then your program's behavior is suddenly more env-dependent.
Also, recursion, while it does not outright stop optimization,
recursive calls are less great than normal calls,
for example they hinder inlining.
Recursion is banned in some coding guidelines:
* SEI CERT DCL56-CPP. Avoid cycles during initialization of static objects
* JPL 2.4 Do not use direct or indirect recursion.
* I'd say it is frowned upon in LLVM, although not banned
And is plain unsupported in some cases:
* OpenCL 1.2, 6.9 Restrictions: i. Recursion is not supported.
So there's clearly a lot of reasons why one might want to
avoid recursion, and replace it with worklist handling.
It would be great to have a enforcement for it though.
This implements such a check.
Here we detect both direct and indirect recursive calls,
although since clang-tidy (unlike clang static analyzer)
is CTU-unaware, if the recursion transcends a single standalone TU,
we will naturally not find it :/
The algorithm is pretty straight-forward:
1. Build call-graph for the entire TU.
For that, the existing `clang::CallGraph` is re-used,
although it had to be modified to also track the location of the call.
2. Then, the hard problem: how do we detect recursion?
Since we have a graph, let's just do the sane thing,
and look for Strongly Connected Function Declarations - widely known as `SCC`.
For that LLVM provides `llvm::scc_iterator`,
which is internally an Tarjan's DFS algorithm, and is used throught LLVM,
so this should be as performant as possible.
3. Now that we've got SCC's, we discard those that don't contain loops.
Note that there may be more than one loop in SCC!
4. For each loopy SCC, we call out each function, and print a single example
call graph that shows recursion -- it didn't seem worthwhile enumerating
every possible loop in SCC, although i suppose it could be implemented.
* To come up with that call graph cycle example, we start at first SCC node,
see which callee of the node is within SCC (and is thus known to be in cycle),
and recurse into it until we hit the callee that is already in call stack.
Reviewers: JonasToth, aaron.ballman, ffrankies, Eugene.Zelenko, erichkeane, NoQ
Reviewed By: aaron.ballman
Subscribers: Charusso, Naghasan, bader, riccibruno, mgorny, Anastasia, xazax.hun, cfe-commits
Tags: #llvm, #clang
Differential Revision: https://reviews.llvm.org/D72362
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
Add a clang-tidy check for using func__/FUNCTION__ inside lambdas. This
evaluates to the string operator(), which is almost never useful and almost
certainly not what the author intended.
Patch by Bryce Liu!
Differential Revision: https://reviews.llvm.org/D33497
llvm-svn: 304570
I have a created a new check for clang tidy: misc-string-compare. This will check for incorrect usage of std::string::compare when used to check equality or inequality of string instead of the string equality or inequality operators.
Example:
```
std::string str1, str2;
if (str1.compare(str2)) {
}
```
Reviewers: hokein, aaron.ballman, alexfh, malcolm.parsons
Subscribers: xazax.hun, Eugene.Zelenko, cfe-commits, malcolm.parsons, Prazek, mgorny, JDevlieghere
Differential Revision: https://reviews.llvm.org/D27210
llvm-svn: 290747
The checker detects various cases when an enum is probably misused
(as a bitmask).
Patch by: Peter Szecsi!
Differential Revision: https://reviews.llvm.org/D22507
llvm-svn: 290600
Summary:
The check warns if an object is used after it has been moved, without an
intervening reinitialization.
See user-facing documentation for details.
Reviewers: sbenza, Prazek, alexfh
Subscribers: beanz, mgorny, shadeware, omtcyfz, Eugene.Zelenko, Prazek, fowles, ioeric, cfe-commits
Differential Revision: https://reviews.llvm.org/D23353
llvm-svn: 281453
Summary:
The check emits a warning if std::move() is applied to a forwarding reference, i.e. an rvalue reference of a function template argument type.
If a developer is unaware of the special rules for template argument deduction on forwarding references, it will seem reasonable to apply std::move() to the forwarding reference, in the same way that this would be done for a "normal" rvalue reference.
This has a consequence that is usually unwanted and possibly surprising: If the function that takes the forwarding reference as its parameter is called with an lvalue, that lvalue will be moved from (and hence placed into an indeterminate state) even though no std::move() was applied to the lvalue at the callsite.
As a fix, the check will suggest replacing the std::move() with a std::forward().
This patch requires D23004 to be submitted before it.
Reviewers: sbenza, aaron.ballman
Subscribers: klimek, etienneb, alexfh, aaron.ballman, Prazek, Eugene.Zelenko, mgehre, cfe-commits
Projects: #clang-tools-extra
Differential Revision: https://reviews.llvm.org/D22220
llvm-svn: 280077
Summary: Finds return statements in assign operator bodies where the return value is different from '*this'. Only assignment operators with correct return value Class& are checked.
Reviewers: aaron.ballman, alexfh, sbenza
Subscribers: o.gyorgy, baloghadamsoftware, LegalizeAdulthood, aaron.ballman, Eugene.Zelenko, xazax.hun, cfe-commits
Differential Revision: http://reviews.llvm.org/D18265
llvm-svn: 268492