Problems for source package rust-signature

BuildDepends

Package declares a build time dependency on librust-rand-core-0.6-dev which cannot be satisfied on mips64el. Package rust-signature does not exist on mips64el.
Package declares a build time dependency on librust-rand-core-0.6-dev which cannot be satisfied on armel. Package rust-signature does not exist on armel.
Package declares a build time dependency on debhelper-compat (= 13) which cannot be satisfied on armel. Package rust-signature does not exist on armel.
Package declares a build time dependency on debhelper-compat (= 13) which cannot be satisfied on mips64el. Package rust-signature does not exist on mips64el.
Package declares a build time dependency on librust-proc-macro2-1+default-dev which cannot be satisfied on mips64el. Package rust-signature does not exist on mips64el.
Package declares a build time dependency on librust-proc-macro2-1+default-dev which cannot be satisfied on armel. Package rust-signature does not exist on armel.
Package declares a build time dependency on librust-hex-literal-0.4+default-dev which cannot be satisfied on armel. Package rust-signature does not exist on armel.
Package declares a build time dependency on librust-hex-literal-0.4+default-dev which cannot be satisfied on mips64el. Package rust-signature does not exist on mips64el.
Package declares a build time dependency on librust-syn-1+default-dev which cannot be satisfied on armel. Package rust-signature does not exist on armel.
Package declares a build time dependency on librust-syn-1+default-dev which cannot be satisfied on mips64el. Package rust-signature does not exist on mips64el.
Package declares a build time dependency on librust-sha2-0.10-dev which cannot be satisfied on mips64el. Package rust-signature does not exist on mips64el.
Package declares a build time dependency on librust-sha2-0.10-dev which cannot be satisfied on armel. Package rust-signature does not exist on armel.
Package declares a build time dependency on librust-digest-0.10-dev which cannot be satisfied on armel. Package rust-signature does not exist on armel.
Package declares a build time dependency on librust-digest-0.10-dev which cannot be satisfied on mips64el. Package rust-signature does not exist on mips64el.
Package declares a build time dependency on librust-quote-1+default-dev which cannot be satisfied on armel. Package rust-signature does not exist on armel.
Package declares a build time dependency on librust-quote-1+default-dev which cannot be satisfied on mips64el. Package rust-signature does not exist on mips64el.
Package declares a build time dependency on dh-sequence-rust which cannot be satisfied on mips64el. Package rust-signature does not exist on mips64el.
Package declares a build time dependency on dh-sequence-rust which cannot be satisfied on armel. Package rust-signature does not exist on armel.