Darryl L. Pierce wrote on 12/04/2014 06:56 AM:

I have a gem I package for Fedora [1] that has a new feature coming with our next release. That feature depends on being able to release the GIL for blocking operations so that other threads in the app can get interpreter time.

The determination as to which GIL-releasing API to call is determined at install time via extconf.rb:

---8<[snip]---

# set the ruby version compiler flag runtime_version = RbConfig::CONFIG["ruby_version"].gsub(/./,"")[0,2] $CFLAGS << " -DRUBY#{runtime_version}"

---8<[snip]---

And in the native code is decides based on whether RUBY19, RUBY20 or RUBY21 is defined (RUBY18 is a noop in this case).

However, on Fedora 19+ and RHEL7 this fails. The reason is because the Ruby package for F19-F22/EL7 returns an empty string for the above value in RbConfig::CONFIG. On Windows, Ubuntu, Debian and the Mac it outputs the version info for the VM.

I filed a BZ for this (BZ#1170282) and would consider this a blocker since I won't be able to release an updated RPM for my gem when we have our next release due to this bug.

Any proven packager here who could give this BZ some lovin' and get a fix pushed?

While here I won't say my opinition for whether ruby_version should be set or not, I closed your report as a duplicate of BZ923703.

BTW skf (I maintain) do the following:

$ ruby -rrbconfig -e'printf "%.1s%.1s\n",RbConfig::CONFIG.fetch("MAJOR"),RbConfig::CONFIG.fetch("MINOR")' 21

Regards, Mamoru