Fix casts to void* #4275
Fix casts to void* #4275
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Actually, hold on confused whether this or #4274 is correct. This is slightly different: std::is_void is equivalent to std::remove_cv_t not std::remove_cvref_t. Which one is actually appropiate here? Which cast should be used for void pointer and references @rwgk @lalaland ? |
If we go by testing, all tests pass with 4 different variants now, from that viewpoint any of those is fine. The best way to answer the question above is to create a full set of tests (c v ref), see what compilers actually accept, then make the tests work the way we want them to. (In this case that's probably only a very small effort.) From an elegance viewpoint, |
References to void are illegal, so std::remove_cv_t and std::remove_cvref_t are equivalent. So std::is_void is preferred. |
| @@ -1179,11 +1179,9 @@ enable_if_t<cast_is_temporary_value_reference<T>::value, T> cast_safe(object &&) | |||
| pybind11_fail("Internal error: cast_safe fallback invoked"); | |||
| } | |||
| template <typename T> | |||
| enable_if_t<std::is_same<void, intrinsic_t<T>>::value, void> cast_safe(object &&) {} | |||
| enable_if_t<std::is_void<T>::value, void> cast_safe(object &&) {} | |||
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Yeah, is std::is_void is more elegant.
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Yes, as noted in #3861, references to void are not allowed in C++, and |
* Fix casts to void* * Improve tests * style: pre-commit fixes * remove c style cast Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com> Co-authored-by: Aaron Gokaslan <aaronGokaslan@gmail.com>
Description
The current code is broken for safe casts to void* as those are incorrectly converted to casts to void. This fixes the problem.
Fixes #4117, needed for #4125
This is a reopened version of #4273 with some minor test changes. Closes #4117.
Suggested changelog entry: