Bug #21692
open
Basic gems like `date` require a compiler
Description
I'm trying to use Ruby in a high security environment which does not allow a compiler to be installed. This was easy years ago when all of standard library was included with Ruby itself and I could use apt install ruby. But as the standard library has broken off into separate, optional gems it has become impossible to bundle a reasonable pure Ruby application without requiring basic gems like date which require a compiler to install.
Are there any plans to make native extensions optional for gems? With tools like ZJIT it can be better to use pure Ruby for performance; I would like to see Ruby encourage fewer native extensions and/or make them optional.
Updated by mame (Yusuke Endoh) about 8 hours ago
I think what you want is bundle install --prefer-local. (I wonder why this option is not the default.)
Updated by getajobmike (Mike Perham) about 7 hours ago
· Edited
- ruby -v changed from 3.4.5 to 3.2.3
mame (Yusuke Endoh) wrote in #note-1:
I think what you want is
bundle install --prefer-local. (I wonder why this option is not the default.)
Unfortunately this does not seem to work for me.
$ gem list | grep date
date (default: 3.3.3)
$ more Gemfile
source "https://rubygems.org"
gem "net-imap"
gem "date", "3.3.3"
$ bundle version
Bundler version 2.5.23 (2024-11-05 commit 35f4611265e)
$ ruby -v
ruby 3.2.3 (2024-01-18 revision 52bb2ac0a6) [x86_64-linux-gnu]
$ bundle install --prefer-local
Fetching gem metadata from https://rubygems.org/...
Resolving dependencies...
Installing date 3.3.3 with native extensions
Gem::Ext::BuildError: ERROR: Failed to build gem native extension.
current directory: /var/lib/gems/3.2.0/gems/date-3.3.3/ext/date
/usr/bin/ruby3.2 -I/usr/lib/ruby/vendor_ruby extconf.rb
checking for rb_category_warn()... *** extconf.rb failed ***
Could not create Makefile due to some reason, probably lack of necessary
libraries and/or headers. Check the mkmf.log file for more details. You may
need configuration options.
[...]
/usr/lib/ruby/3.2.0/mkmf.rb:490:in `try_do': The compiler failed to generate an executable file. (RuntimeError)
You have to install development tools first.
Updated by mame (Yusuke Endoh) 4 minutes ago
Ah, it seems this happens on Ubuntu 24.04, without a Gemfile.lock, and when the Gemfile does not list the indirect dependencies.
I found three workarounds.
1. Add a Gemfile.lock
¶
If a proper Gemfile.lock is present, --prefer-local seems to avoid the installation.
$ ls
Gemfile Gemfile.lock
$ cat Gemfile
source "https://rubygems.org"
gem "net-imap"
gem "date", "3.3.3"
$ cat Gemfile.lock
GEM
remote: https://rubygems.org/
specs:
date (3.3.3)
net-imap (0.3.4.1)
date
net-protocol
net-protocol (0.2.1)
timeout
timeout (0.3.1)
PLATFORMS
x86_64-linux-gnu
DEPENDENCIES
date (= 3.3.3)
net-imap
BUNDLED WITH
2.4.20
$ bundle install --prefer-local
Bundle complete! 2 Gemfile dependencies, 5 gems now installed.
Use `bundle info [gemname]` to see where a bundled gem is installed.
2. List all dependencies in the Gemfile¶
If the Gemfile lists all dependencies, including the indirect ones, --prefer-local also seems to avoid the installation.
$ ls
Gemfile
$ cat Gemfile
source "https://rubygems.org"
gem "timeout"
gem "net-protocol"
gem "net-imap"
gem "date", "3.3.3"
$ bundle install --prefer-local
Resolving dependencies...
Bundle complete! 4 Gemfile dependencies, 5 gems now installed.
Use `bundle info [gemname]` to see where a bundled gem is installed.
3. Use bundler from a newer Ubuntu release¶
I think this behavior is a bug in the older version of bundler. With Ubuntu 25.10, it works well as expected, as shown below:
$ ls
Gemfile
$ cat Gemfile
source "https://rubygems.org"
gem "net-imap"
gem "date", "3.3.4"
$ bundle install --prefer-local
Fetching gem metadata from https://rubygems.org/...
Resolving dependencies...
Bundle complete! 2 Gemfile dependencies, 5 gems now installed.
Use `bundle info [gemname]` to see where a bundled gem is installed.