New review comment by AlaskanEmily on void-packages repository https://github.com/void-linux/void-packages/pull/36905#discussion_r881085280 Comment: > this should happen in do_install Mercury's makefiles do a majority of their actual compilation in the `install` phase. The default rule builds the bootstrap compiler, and then `make install` actually builds the development files that this compiler will use. It's not ideal, but it's not going to change upstream. The `DESTDIR` variable to the makefile was added for the Debian packages to get around this, and is specifically to say what the build directory should be in this case, so that `install` targets that instead of the actual prefix we want to install to. This is why we can't do `make install` in `do_install`, unfortunately.