Chazelle's break-out 2014 film "Whiplash," about a driven jazz student and equally driven music teacher, earned a Best Supporting Actor Oscar for Simmons this year.
Legend, who co-wrote the Oscar-winning song "Glory" from the film "Selma," reportedly will compose songs as well as act and sing in "La La Land." The film is scheduled for release July 15, 2016.
Gosling is working on yet another musical project as well. Warner Bros. has optioned the biopic "Buzz: The Life and Art of Busby Berkeley," about the life of choreographer, director, performer, producer and production supervisor Busby Berkeley, according to the Hollywood Reporter.
The project, based on the biography of the same name by Jeffrey Spivak, would be produced by Gosling and Marc Platt (If/Then, Pal Joey, Wicked, Three Days Rain, Total Abandon), with Gosling to star and possibly direct. Gosling and Platt previously worked together on the indie crime movie "Drive." Berkeley, known for films such as "42nd Street," "Gold Diggers of 1935," "For Me and My Gal" and "Romance on the High Seas," was the choreographer of Broadway's The Wild Rose, White Eagle, Present Arms, Earl Carroll's Vanities of 1928, Good Boy, Rainbow, Pleasure Bound, A Night in Venice, Broadway Nights, Nine-fifteen Revue and The International Review, among others. He was the production supervisor of No, No, Nanette.
Berkeley was a three-time Oscar nominee for Best Dance Direction of "Varsity Show," "Gold Diggers of 1937" and "Gold Diggers of 1935."
Chantal Nong will oversee the project for Warner Bros.