From http://llvm.org/docs/DeveloperPolicy.html#license:

"LLVM’s license is not a “copyleft” license like the GPL."

Rights to copy the source is not what copyleft means.

No it isn't copyleft, I'm not sure you know what "copyleft" means.

Open source: yes

Free/Libre software: yes (https://www.gnu.org/philosophy/license-list.html#GPLCompatib...)

Copyleft: no

The word "copyleft" has a meaning. Please, don't polute the discussion with missleading political speech trying to change its meaning.