Q: middle-end problem when variadic builtins promote float to double

Joseph S. Myers joseph@codesourcery.com
Fri Jul 6 21:25:00 GMT 2007

On Fri, 6 Jul 2007, Kaveh R. GHAZI wrote:

> So how do we detect or work around this promotion issue and discriminate
> between the case where a float is promoted because of the variadic
> prototype vs a user supplied cast or other user code?

I think we may need to tag these builtins in some way to indicate to the 
front ends that arguments shouldn't be promoted.  (With some other 
builtins, such as __builtin_printf, the normal C promotion rules should be 

Joseph S. Myers

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