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From: "dcrocker at eschertech dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/48379] -Wdouble-promotion warns for promotion by varargs
Date: Tue, 18 Oct 2022 14:29:32 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D48379

David Crocker <dcrocker at eschertech dot com> changed:

           What    |Removed                     |Added
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                 CC|                            |dcrocker at eschertech dot=
 com

--- Comment #4 from David Crocker <dcrocker at eschertech dot com> ---
I too am getting fed up with having to add an explicit cast to double to
suppress the warning whenever I pass a float to a varargs function. I have
probably spent a few hours this year adding these casts. As has already been
said, nothing can he done about the promotion in this context, so it's not
worth warning about. Whereas in other situations, the warning is very usefu=
l to
me because I work with embedded processors that have single-precision but n=
ot
double-precision floating point hardware, so I want to avoid double precisi=
on
maths as far as possible.=