I know that the Argentinian composer and singer Víctor Heredia wrote some great songs based on Neruda's poems, including some (or at least one) from 'Canto General'.
One reference: http://www.infobae.com/notas/nota.php?Idx=136337&IdxSeccion=100442
(...) El cierre estuvo a cargo del cantante argentino Víctor Heredia, que interpretó Alturas del Machú Pichu, un poema del libro Canto General del escritor chileno.(...)
Note: they were probably talking about the song 'Sube conmigo, amor americano'.
Claudia Iglesias wrote:
My father is doing an investigation and compiling songs inspired by Pablo Neruda's poems in the Canto General (I supposed that the name was translated into all languages, "General Song" in English).
I know some (Quilapayún or Mikis Theodorakis), my father knows many others, but I'd like to ask you whether you know any (in any language).
That would be great.
Thank you very much
NOTE ADDED. AFAIK, there are three songs composed by Víctor Heredia from 'Canto General':
-Sube conmigo, amor americano
-El pueblo victorioso
-Por estos muertos
[Edited at 2006-08-07 03:49]