[clang-tools-extra] [clang-tidy] Added bugprone-exception-rethrow check (PR #86448)

via cfe-commits cfe-commits at lists.llvm.org
Sun Apr 28 14:35:16 PDT 2024


================
@@ -0,0 +1,67 @@
+.. title:: clang-tidy - bugprone-exception-rethrow
+
+bugprone-exception-rethrow
+==========================
+
+Identifies problematic exception rethrowing, especially with caught exception
+variables or empty throw statements outside catch blocks.
+
+In C++ exception handling, a common pitfall occurs when developers rethrow
+caught exceptions within catch blocks by directly passing the caught exception
+variable to the ``throw`` statement. While this approach can propagate
+exceptions to higher levels of the program, it often leads to code that is less
+clear and more error-prone. Rethrowing caught exceptions with the same exception
+object within catch blocks can obscure the original context of the exception and
+make it challenging to trace program flow. Additionally, this method can
+introduce issues such as exception object slicing and performance overhead due
+to the invocation of the copy constructor.
+
+.. code-block:: c++
+
+  try {
+    // Code that may throw an exception
+  } catch (const std::exception& e) {
+    throw e; // Bad
+  }
+
+To prevent these issues, it is advisable to utilize ``throw;`` statements to
+rethrow the original exception object for currently handled exceptions.
+
+.. code-block:: c++
+
+  try {
+    // Code that may throw an exception
+  } catch (const std::exception& e) {
+    throw; // Good
+  }
+
+However, when empty throw statement is used outside of a catch block, it
+will result in a call to ``std::terminate()``, which abruptly terminates the
----------------
isuckatcs wrote:

```suggestion
However, when an empty throw statement is used outside a catch block, it
results in a call to ``std::terminate()``, which abruptly terminates the
```

https://github.com/llvm/llvm-project/pull/86448


More information about the cfe-commits mailing list