Rapper Mac Miller was found dead Friday inside his California home. He was 26.
According to TMZ, he died of an apparent overdose.
Canada's Shawn Mendes reacted to the news on Twitter. "Unreal. So sad," he shared.
Chance the Rapper tweeted: "Mac Miller took me on my second tour ever. But beyond helping me launch my career he was one of the sweetest guys I ever knew. Great man. I loved him for real. Im completely broken."
Songwriter and OneRepublic frontman Ryan Tedder remembered Miller as "a super nice, funny and warm dude." Charlie Puth tweeted: "This sucks this really really sucks."
Miller, whose real name was Malcolm James McCormick, released the album Swimming last month and was due to start a U.S. tour on Oct. 27 in San Francisco. Miller was scheduled to perform Nov. 25 in Toronto and Dec. 10 in Vancouver.
The "Self Care" rapper had been open about his struggles with addiction.
When his relationship with pop star Ariana Grande ended in May, she tweeted: "I have cared for him and tried to support his sobriety and prayed for his balance for years (and always will of course) but shaming/blaming women for a man's inability to keep his s**t together is a very major problem."
Shortly after their split, Miller was arrested on suspicion of DUI and a hit-and-run.
"God f**king dammit," Post Malone tweeted. "You were such an incredible person. You changed so many lives. Had so much love in your heart. You inspired me throughout highschool, and I wouldn't be where I was today without you.
"Never a more kind and sincere and beautiful person. I f**king love you mac."