===> Skipping vulnerability checks.
WARNING: No /usr/pkg/pkgdb/pkg-vulnerabilities file found.
WARNING: To fix run: `/usr/sbin/pkg_admin -K /usr/pkg/pkgdb fetch-pkg-vulnerabilities'.
===> Building for kalker-2.2.2
   Compiling libc v0.2.172
   Compiling proc-macro2 v1.0.95
error: could not compile `proc-macro2` (build script)

Caused by:
  could not execute process `rustc --crate-name build_script_build --edition=2021 /pbulk/work/math/kalker/work/vendor/proc-macro2-1.0.95/build.rs --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --crate-type bin --emit=dep-info,link -C embed-bitcode=no -C debug-assertions=off --cfg 'feature="default"' --cfg 'feature="proc-macro"' --check-cfg 'cfg(docsrs,test)' --check-cfg 'cfg(feature, values("default", "nightly", "proc-macro", "span-locations"))' -C metadata=6267ff0d8b60e8f9 -C extra-filename=-503a6b8f31c185b8 --out-dir /pbulk/work/math/kalker/work/kalker-2.2.2/target/release/build/proc-macro2-503a6b8f31c185b8 -C strip=debuginfo -L dependency=/pbulk/work/math/kalker/work/kalker-2.2.2/target/release/deps --cap-lints allow` (never executed)

Caused by:
  No such file or directory (os error 2)
*** Error code 101

Stop.
make[1]: stopped in /usr/pkgsrc/math/kalker
*** Error code 1

Stop.
make: stopped in /usr/pkgsrc/math/kalker