Re: lang/rust with gcc10 (Re: diff from 2025-05-14 03:12 to 2025-05-17 10:36

[Havard Eidnes <he%NetBSD.org@localhost>]

> Havard Eidnes <he%NetBSD.org@localhost> writes:
> 
>> Insisting on a full analysis of what the underlying root problem
>> is is actually a quite tall order, especially given the size and
>> complexity of lang/rust, so if that's going to be a barrier to
>> making it buildable, that will probably cause it to be
>> un-buildable for the given combination an extended time period if
>> not indefinately.  I'll claim that is actually a worse way to
>> deal with the issue than applying a known workaround..
> 
> Maybe so, but just adding the workaround without a comment with all of
> the known information, and without explaining that it's the wrong
> approach but nobody has any better ideas, is not an ok thing to do.
> The next person to read the makefile will have no idea why.
> 
> So it could be explaining that while upstream documentations X, and gcc
> says that Y should be sufficent, Y fails, and Z works, and we therefore
> set it to Z, even though that's a kludge and masks a real, unknown bug.

With reference to recent discussion on tech-pkg%NetBSD.org@localhost, would
this diff satisfy the above?

diff --git a/rust187/options.mk b/rust187/options.mk
index 999196b96b..1ddbbdc0eb 100644
--- a/rust187/options.mk
+++ b/rust187/options.mk
@@ -48,6 +48,18 @@ GCC_REQD+=	12
 GCC_REQD+=	14
 .endif
 
+# Apparently, using pkgsrc LLVM 19.x does not work on
+# NetBSD/x86_64 9.x unless rust is built with a newer
+# gcc than the platform-included 7.5.0.  Ref.
+# https://gnats.netbsd.org/59435 and
+# https://mail-index.netbsd.org/pkgsrc-users/2025/05/20/msg041603.html
+# and following discussion.
+.if empty(PKG_OPTIONS:Mrust-internal-llvm)
+.  if ${MACHINE_PLATFORM:MNetBSD-9.*-x86_64}
+GCC_REQD+=	10
+.  endif
+.endif
+
 #
 # Use the internal copy of LLVM or the external one?
 #

I'm currently validating whether it fixes the issue in my case,
and will need to rebuild at least curl, cmake, libunwind and llvm
before that can be attempted.

Regards,

- Havard