lang/rust build failure

[Paul Goyette <paul%whooppee.com@localhost>]

With up-to-date pkgsrc, and running on amd64 NetBSD-9/99/46 host, I am
getting an error trying to build rust.  All dependencies have already
been rebuilt (in a clean sandbox, as created by sysutils/mksandbox).

The error seems to be a linker error while building rustdoc-tool

  = note: ld: cannot find -lLLVM-9

error: aborting due to previous error

error: could not compile `rustdoc-tool`.

To learn more, run the command again with --verbose.

command did not execute successfully: "/tmp/pkgs/lang/rust/work.x86_64/rust-bootstrap/bin/cargo" "build" "-Zconfig-profile" "--target" "x86_64-unknown-netbsd" "-Zbinary-dep-depinfo" "-j" "1" "--release" "--frozen" "--manifest-path" "/tmp/pkgs/lang/rust/work.x86_64/rustc-1.41.0-src/src/tools/rustdoc/Cargo.toml"expected success, got: exit code: 101

Traceback (most recent call last):
  File "./x.py", line 11, in <module>
    bootstrap.main()
  File "/tmp/pkgs/lang/rust/work.x86_64/rustc-1.41.0-src/src/bootstrap/bootstrap.py", line 919, in main
    bootstrap(help_triggered)
  File "/tmp/pkgs/lang/rust/work.x86_64/rustc-1.41.0-src/src/bootstrap/bootstrap.py", line 905, in bootstrap
    run(args, env=env, verbose=build.verbose)
  File "/tmp/pkgs/lang/rust/work.x86_64/rustc-1.41.0-src/src/bootstrap/bootstrap.py", line 141, in run
    raise RuntimeError(err)
RuntimeError: failed to run: 
/tmp/pkgs/lang/rust/work.x86_64/rustc-1.41.0-src/build/bootstrap/debug/bootstrap -v build -j 1
*** Error code 1



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| Paul Goyette       | PGP Key fingerprint:     | E-mail addresses:     |
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