Comment by fuhsnn

5 hours ago

> C23 gave us [[cleanup]] attributes

C23 didn't introduce it, it's still a GCC extension that needs to be spelled as [[gnu::cleanup()]] https://godbolt.org/z/Gsz9hs7TE

4 comments

fuhsnn

cassepipe 5 hours ago

It is surprisingly hard to find information about it, do you have any ? From what I can guess it's a new syntax but it's the feature itself is still an extension ?

ksherlock 4 hours ago

[[ ]] attributes were added in C++11 and later C23. There are 7 standard(C32) attributes but GCC has hundreds of them.
https://en.cppreference.com/w/c/language/attributes.html
https://en.cppreference.com/w/cpp/language/attributes.html
https://gcc.gnu.org/onlinedocs/gcc/Attributes.html
https://gcc.gnu.org/onlinedocs/gcc/Common-Variable-Attribute...
SAI_Peregrinus 4 hours ago

The `[[attribute]]` syntax is new, the builtin ones in C23 are `[[deprecated]]`, `[[fallthrough]]`, `[[maybe_unused]]`, `[[nodiscard]]`, `[[noreturn]]`, `[[reproducible]]`, and `[[unsequenced]]`.
kccqzy 3 hours ago

The feature itself is probably still __attribute__((cleanup(f))). That’s documented at https://gcc.gnu.org/onlinedocs/gcc/Common-Variable-Attribute...