Add MAKE_INSTALL_OPTS configuration option

README.md

@@ -119,6 +119,7 @@ You can set certain environment variables to control the build process.
 * `MAKE` lets you override the command to use for `make`. Useful for specifying
   GNU make (`gmake`) on some systems.
 * `MAKE_OPTS` (or `MAKEOPTS`) lets you pass additional options to `make`.
+* `MAKE_INSTALL_OPTS` lets you pass additional options to `make install`.
 * `RUBY_CONFIGURE_OPTS`, `RUBY_MAKE_OPTS` and `RUBY_MAKE_INSTALL_OPTS` allow
   you to specify configure and make options for buildling MRI. These variables
   will be passed to Ruby only, not any dependent packages (e.g. libyaml).

bin/ruby-build

@@ -411,7 +411,7 @@ build_package_standard() {
   ) >&4 2>&1
 
   { "$MAKE" $MAKE_OPTS ${!PACKAGE_MAKE_OPTS} "${!PACKAGE_MAKE_OPTS_ARRAY}"
-    "$MAKE" install ${!PACKAGE_MAKE_INSTALL_OPTS} "${!PACKAGE_MAKE_INSTALL_OPTS_ARRAY}"
+    "$MAKE" $MAKE_INSTALL_OPTS install ${!PACKAGE_MAKE_INSTALL_OPTS} "${!PACKAGE_MAKE_INSTALL_OPTS_ARRAY}"
   } >&4 2>&1
 }