Don't think so. It might sound like David Gilmour, but it's not him.. So who could it be?
I remember the day I got to know who the lead singer in this song were! It was a time after the first Roger Waters tour, and after I listened to this song ALL THE TIME! Then I thought that this could not be anyone in the band who is singing. I couldn't recognize the voice at all! So I just got more and more frustrated.. Yes, I could have used the internet, but I wanted to try to find the owner of the voice on my own. And then I got tired of searching on my own, so then I started to look on the internet, and I found this one page who said it was David who was singing, and I felt so stupid.. :p Thought I had some control on the voices.. And then I forgot about it for about a year, and than, out of the blue, I got myself a Pink Floyd book, and there it was. black print on white paper. "The band had a guest vocal on "Have a cigar","... I KNEW IT!! He's name is Roy Harper, and he is a singer, of course. They were recording in Abby Road studio, Pink Floyd in studio 3 and Roy Harper in studio 2. Since David wouldn't sing this song (I'm still not sure why), Roy offered to sing this song. FANTASTIC!!!
Here's the man!! He actually hasn't got paid for his singing on the album... And he's not happy about it, since he means that the album OR song wouldn't been the same if he didn't help the band out!
"Have a cigar" is one of two songs that are not sung by anyone in the band!!! The other song is "The great gig in the sky". That's not even a mystery, since the vocals is sung by a woman... ;)
Clare Torry, "The great gig in the sky"