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(cherry picked from commit 474fc4078acbe062fcc31ce91c69c8f33bf00d5f)
Change-Id: I9f78f7afd8468d0ab676c0f60c4f7d6140128583
This commit is contained in:
eldritch horrors 2024-03-08 07:48:31 +01:00
parent f27a27f49e
commit f536696b73
2 changed files with 9 additions and 23 deletions

View file

@ -91,7 +91,7 @@ void EvalErrorBuilder<T>::debugThrow()
// `EvalState` is the only class that can construct an `EvalErrorBuilder`, // `EvalState` is the only class that can construct an `EvalErrorBuilder`,
// and it does so in dynamic storage. This is the final method called on // and it does so in dynamic storage. This is the final method called on
// any such instancve and must delete itself before throwing the underlying // any such instance and must delete itself before throwing the underlying
// error. // error.
auto error = std::move(this->error); auto error = std::move(this->error);
delete this; delete this;

View file

@ -57,6 +57,11 @@ public:
} }
}; };
/**
* `EvalErrorBuilder`s may only be constructed by `EvalState`. The `debugThrow`
* method must be the final method in any such `EvalErrorBuilder` usage, and it
* handles deleting the object.
*/
template<class T> template<class T>
class EvalErrorBuilder final class EvalErrorBuilder final
{ {
@ -91,29 +96,10 @@ public:
[[nodiscard, gnu::noinline]] EvalErrorBuilder<T> & [[nodiscard, gnu::noinline]] EvalErrorBuilder<T> &
addTrace(PosIdx pos, std::string_view formatString, const Args &... formatArgs); addTrace(PosIdx pos, std::string_view formatString, const Args &... formatArgs);
/**
* Delete the `EvalErrorBuilder` and throw the underlying exception.
*/
[[gnu::noinline, gnu::noreturn]] void debugThrow(); [[gnu::noinline, gnu::noreturn]] void debugThrow();
}; };
/**
* The size needed to allocate any `EvalErrorBuilder<T>`.
*
* The list of classes here needs to be kept in sync with the list of `template
* class` declarations in `eval-error.cc`.
*
* This is used by `EvalState` to preallocate a buffer of sufficient size for
* any `EvalErrorBuilder<T>` to avoid allocating while evaluating Nix code.
*/
constexpr size_t EVAL_ERROR_BUILDER_SIZE = std::max({
sizeof(EvalErrorBuilder<EvalError>),
sizeof(EvalErrorBuilder<AssertionError>),
sizeof(EvalErrorBuilder<ThrownError>),
sizeof(EvalErrorBuilder<Abort>),
sizeof(EvalErrorBuilder<TypeError>),
sizeof(EvalErrorBuilder<UndefinedVarError>),
sizeof(EvalErrorBuilder<MissingArgumentError>),
sizeof(EvalErrorBuilder<InfiniteRecursionError>),
sizeof(EvalErrorBuilder<CachedEvalError>),
sizeof(EvalErrorBuilder<InvalidPathError>),
});
} }