[clang-tools-extra] [clang-tidy] Add check 'bugprone-unsafe-to-allow-exceptions' (PR #176430)

[Baranov Victor via cfe-commits]

=?utf-8?q?Balázs_Kéri?= <balazs.keri at ericsson.com>,
=?utf-8?q?Balázs_Kéri?= <balazs.keri at ericsson.com>,
=?utf-8?q?Balázs_Kéri?= <balazs.keri at ericsson.com>,
=?utf-8?q?Balázs_Kéri?= <balazs.keri at ericsson.com>,
=?utf-8?q?Balázs_Kéri?= <balazs.keri at ericsson.com>
Message-ID:
In-Reply-To: <llvm.org/llvm/llvm-project/pull/176430 at github.com>


================
@@ -0,0 +1,41 @@
+.. title:: clang-tidy - bugprone-unsafe-to-allow-exceptions
+
+bugprone-unsafe-to-allow-exceptions
+===================================
+
+Finds functions where throwing exceptions is unsafe but the function is still
+marked as potentially throwing. Throwing exceptions from the following
+functions can be problematic:
+
+* Destructors
+* Move constructors
+* Move assignment operators
+* The ``main()`` functions
+* ``swap()`` functions
+* ``iter_swap()`` functions
+* ``iter_move()`` functions
+
+A destructor throwing an exception may result in undefined behavior, resource
+leaks or unexpected termination of the program. Throwing move constructor or
+move assignment also may result in undefined behavior or resource leak. The
+``swap()`` operations expected to be non throwing most of the cases and they
+are always possible to implement in a non throwing way. Non throwing ``swap()``
+operations are also used to create move operations. A throwing ``main()``
+function also results in unexpected termination.
+
+The check finds any of these functions if it is marked with ``noexcept(false)``
+or ``throw(exception)``. This would indicate that the function is expected to
----------------
vbvictor wrote:

What about functions that don't have any explicit exception spec?
Those are also considered as throwing, I think we should check them too or I am missing something? 

https://github.com/llvm/llvm-project/pull/176430