Firefox-56 brought us to rust-1.20, which fails to package on -current amd64 - the generated .so library files have different names than the expected in the PLIST. 'make' completes apparently OK. 'make package' gives:
=> Bootstrap dependency digest>=20010302: found digest-20160304
=> Creating binary package /usr/pkgsrc/lang/rust/work/.packages/rust-1.20.0.tgz
pkg_create: can't stat `/usr/pkgsrc/lang/rust/work/.destdir/usr/pkg/lib/libarena-f5f78bba81916a46.so'
pkg_create: can't stat `/usr/pkgsrc/lang/rust/work/.destdir/usr/pkg/lib/libfmt_macros-0b9124250167dd63.so'
pkg_create: can't stat `/usr/pkgsrc/lang/rust/work/.destdir/usr/pkg/lib/libgraphviz-9a58d125030e538c.so'
pkg_create: can't stat `/usr/pkgsrc/lang/rust/work/.destdir/usr/pkg/lib/libproc_macro-adb45ea4da914940.so'
pkg_create: can't stat `/usr/pkgsrc/lang/rust/work/.destdir/usr/pkg/lib/librustc-6a534897b169ca84.so'
and many more. work/.destdir/usr/pkg/lib/libarena-732860ab4dbd6111.so is, as an example, the name of the present file - for the first missing.
Have I missed something? I updated a few other packages which got bumped up with rust, e.g. llvm, but haven't gone to full update of the pkgsrc tree - I dread the prospect of recompiling about 1700 packages on an old ThinkPad T61p...