Description of problem:

The version of the Ruby VM is checked using the standard config value for "ruby_version", which is kept in RbConfig::CONFIG. However, on the Ruby versions released with F19, F20, F21 and RHEL7 this config value returns an empty string rather than the version string.


Version-Release number of selected component (if applicable):

All versions of the ruby package on F19, F20, F21 and EL7. EL6 works as expected.


How reproducible:

100%

Steps to Reproduce:
1. Install IRB.
2. From the command prompt, type "irb".
3. From within irb enter : RbConfig::CONFIG["ruby_version"]

Actual results:

An empty string is returned.


Expected results:

The version of the Ruby VM being uses, such as:

"1.9.3"
"2.0.0"


Additional info:

Verifying the appropriate expectation using RVM I checked 1.8, 1.9 and 2.0 and found that Ruby always returns the version string. Also verified on Debian and Ubuntu 14.