compiler-rt fails to build on NetBSD

[gandro]

With the compiler-rt update in PR #29478, gcc_personality_v0.c now includes the unwind.h header to deduplicate some type definitions (commit: rust-lang/compiler-rt@5f0c79f) .

The unwind.h header available in NetBSD however does not provide all required definitions. Specifically, _Unwind_Action is absent in this header, leading to the following build failure:

.../rust/src/compiler-rt/lib/builtins/gcc_personality_v0.c:151:35: error: unknown type name '_Unwind_Action'
__gcc_personality_v0(int version, _Unwind_Action actions,
                                  ^

Side note: As far as I understand, NetBSD provides the above header only if the platform uses libgcc_eh (e.g. on amd64 using gcc, which is supported by Rust currently). Otherwise, LLVM's libunwind header is installed, which contains the required definitions.

I'm not sure how to fix this. Should Rust's compiler-rt duplicate the type definitions again?

[alexcrichton]

Ah this may have just been missed out in the compiler-rt update, it should be fine to basically pull in whatever the same fix was previously again.

[jakllsch]

The correct unwind.h is also available via the libunwind package from pkgsrc. But that may or may not be a good solution.

[jakllsch]

Looked at this more. https://nxr.netbsd.org/xref/src/lib/libc/compiler_rt/Makefile.inc?r=1.30#29 and https://nxr.netbsd.org/xref/src/share/mk/bsd.own.mk?r=1.938#127 shows that gcc_personality_v0.c is only used on EABI ARM machines, which rustc for NetBSD does not currently target. I'll probably have a patch to address that just forces HAVE_UNWIND_H=OFF on NetBSD/non-ARM.

[alexcrichton]

I believe this is no longer being built, so closing.