unable to install: Option '--docdir=/usr/local/share/doc/rust' is not recognized

[nickdesaulniers]

after a successful configure and make from top of tree, make install fails:

...
gen-install-script: 
gen-install-script: CFG_PRODUCT_NAME     := Rust-Documentation 
gen-install-script: CFG_REL_MANIFEST_DIR := rustlib 
gen-install-script: CFG_SUCCESS_MESSAGE  := Rust-documentation-is-installed. 
gen-install-script: CFG_OUTPUT_SCRIPT    := tmp/dist/rust-docs-1.13.0-dev-x86_6 ...
gen-install-script: CFG_LEGACY_MANIFEST_DIRS := rustlib,cargo 
gen-install-script: 
gen-install-script: validating arguments
gen-install-script: 
install: error: Option '--docdir=/usr/local/share/doc/rust' is not recognized

[jedisct1]

Duplicate of #36451

[alexcrichton]

Indeed closing as a dupe