reference to local binding fails in enclosing function

[yurivict]

Bugzilla Link	49238
Version	12.0
OS	FreeBSD
Attachments	testcase-clang.cpp
CC	@zygoloid

Extended Description

The attached testcase fails in clang++{9,10,11}:

testcase-clang.cpp:11:16: error: reference to local binding 'a' declared in enclosing function 'f'
return a+b;
^
testcase-clang.cpp:9:11: note: 'a' declared here
auto [a, b] = newTuple();
^
testcase-clang.cpp:11:18: error: reference to local binding 'b' declared in enclosing function 'f'
return a+b;
^
testcase-clang.cpp:9:14: note: 'b' declared here
auto [a, b] = newTuple();
^
2 errors generated.

It succeeds in gcc-10.

[llvmbot]

(For reference, if I understand correctly, this should be allowed by P1091R3 and/or P1381R1; I have also tested this against clang 12.0.5.)

[llvmbot]

Yes C++20 does fix this but Clang still complains about it.

[yurivict]

I just checked clang-14 - it is still affected.

Is there an estimate when this will be fixed?

[planetmarshall]

Short test case on Compiler Explorer

https://godbolt.org/z/n99xe57vs

[llvmbot]

@llvm/issue-subscribers-clang-frontend

[chausner]

Short test case on Compiler Explorer

https://godbolt.org/z/n99xe57vs

Seems the issue has been fixed in the latest development version (clang (trunk) on Compiler Explorer).