[PATCH] D33537: [clang-tidy] Exception Escape Checker

[Alexander Kornienko via Phabricator via cfe-commits]

alexfh requested changes to this revision.
alexfh added inline comments.
This revision now requires changes to proceed.


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Comment at: docs/clang-tidy/checks/bugprone-exception-escape.rst:6
+
+Finds functions which should not throw exceptions:
+* Destructors
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I don't think the check just finds functions that should not throw exceptions. I suppose, it finds `throw` statements inside them (or maybe it goes slightly deeper - the documentation should explain this in more detail). See also the comment @dberris left below.


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Comment at: docs/clang-tidy/checks/bugprone-exception-escape.rst:31
+   ``WinMain()`` in the Windows API to the list of the funcions which should
+   not throw.. Default value is empty string.
+
----------------
nit: Double period after `throw`.


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Comment at: docs/clang-tidy/checks/bugprone-exception-escape.rst:31
+   ``WinMain()`` in the Windows API to the list of the funcions which should
+   not throw.. Default value is empty string.
+
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alexfh wrote:
> nit: Double period after `throw`.
nit: "an empty string"
Same below.


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Comment at: test/clang-tidy/bugprone-exception-escape.cpp:178
+void indirect_implicit() noexcept {
+  // CHECK-MESSAGES: :[[@LINE-1]]:6: warning: function 'indirect_implicit' throws
+  implicit_int_thrower();
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baloghadamsoftware wrote:
> lebedev.ri wrote:
> > baloghadamsoftware wrote:
> > > dberris wrote:
> > > > How deep does this go? Say we have a call to a function that's extern which doesn't have 'noexcept' nor a dynamic exception specifier -- do we assume that the call to an extern function may throw? Does that warn? What does the warning look like? Should it warn? How about when you call a function through a function pointer?
> > > > 
> > > > The documentation should cover these cases and/or more explicitly say in the warning that an exception may throw in a noexcept function (rather than just "function <...> throws").
> > > We take the most conservative way here. We assume that a function throws if and only if its body has a throw statement or its header has the (old) throw() exception specification. We do not follow function pointers.
> > While i realize it may have more noise, it may be nice to have a more pedantic mode (guarded by an option?).
> > E.g. `noexcept` propagation, much like `const` on methods propagation.
> > Or at least a test that shows that it does not happen, unless i simply did not notice it :)
> This could be an enhancement in the future, yes.
Please address the original comment here. In particular, the warning message should be clearer (that an exception may be thrown in a function that should not throw exceptions).


https://reviews.llvm.org/D33537