Renaming a tag causes failure?

[ghost]

After renaming a tag, the versioning call introduces a build failure. The output from git-describe shows:

$ git describe --tags --always --first-parent
warning: tag '2.6.0' is externally known as 'v2.6.0'
v2.6.0-0-gbf1b957

Note that the warning is written to standard error, which can be suppressed:

$ git describe --tags --always --first-parent 2> /dev/null
v2.6.0-0-gbf1b957

Depending on the implementation, consider reading standard output, exclusively.