installation in specified prefix doesn't work, tries to create '/usr/local/Modules'

[boegel]

Describe the bug

Installing in a specified prefix fails, because "make install" tries to create /usr/local/Modules:

$ ./configure --prefix /tmp/example
$ make install
...
mkdir -p /usr/local/Modules/libexec
mkdir: cannot create directory ‘/usr/local/Modules’: Permission denied
make: *** [install] Error 1

This triggers are Permission denied because I'm using a non-admin user account.

To Reproduce

Steps to reproduce the behavior:

$ tar xfvz modules-4.5.1.tar.gz
$ cd modules-4.5.1
$ ./configure --prefix /tmp/example
$ make install
...

Expected behavior

Installation to specified prefix works.

Error and debugging information

$ make install
mkdir -p /usr/local/Modules/libexec
mkdir: cannot create directory ‘/usr/local/Modules’: Permission denied
make: *** [install] Error 1
...

Modules version and configuration

Modules 4.5.1, 4.5.0, 4.4.1

Additional context

(none)

[boegel]

I've danced around this issue by replacing all occurences of /usr/local/Modules with my preferred prefix in Makefile.inc after running configure.

[xdelaruelle]

Thanks for your detailed report @boegel.

--prefix value should be given in the --arg=value form. So here there are 2 issues:

• an error should be raised if an unknown argument is used, ./configure cannot silently ignore it
• --arg value form seems commonly used so it should also be supported