| Issue |
113747
|
| Summary |
[clang] __attribute__((__noreturn__)) miscompile
|
| Labels |
clang
|
| Assignees |
|
| Reporter |
ZijunZhaoCCK
|
`__attribute__((__noreturn__))` is miscompiled upstream.
See https://godbolt.org/z/T6nMoa75G from Miguel Young and his comment.
```
When using the standard [[noreturn]] and _Noreturn in their respective languages, codegen is identical, and correct. The C codegen is obviously wrong and clearly confusing the hell out of LLVM, as evidenced by this instruction sequence:
jne .LBB1_1
mov rax, qword ptr [rip + baz@GOTPCREL]
call rax
.LBB1_1: mov rax, qword ptr [rip + foo@GOTPCREL] call rax
(Just do call foo@PLT?)
My recommendation is that upstream use _Noreturn, or noreturn + <stdnoreturn.h>. Clang is clearly able to get this right, but somehow left hand isn't talking to right hand in the unification algorithm.
(This really isn't a C v. C++ difference at all; both languages define their standard noreturn primitives identically.)
```
![]()
_______________________________________________
llvm-bugs mailing list
[email protected]
https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-bugs
