Re: I'm sorry, but this is unacceptable (union members and ctors)

[Andrew Haley <aph-gcc at littlepinkcloud dot COM>]

Robert Dewar writes:
 > Ross Ridge wrote:
 > t formal definition.
 > 
 > > Most of GCC's long list of extensions to C are also implemented as
 > > extensions to C++, so you've already lost this battle in GNU C++.
 > 
 > And many of them are ill-defined (and some would agree ill-considered).
 > Mistakes in the past are not a good reason for mistakes in the future.
 > 
 > > Trying to add new a new feature without an existing implementation only
 > > makes it harder to get both a correct formal definition and something
 > > that people will actually want to use.
 > 
 > I think the best procedure is to discuss new features from a language
 > design point of view, and the committee is the best forum for that,
 > then implement them as *part* of the (typically fairly drawn out)
 > process of adding a new feature.

There's always a "chicken and egg" problem here: language features
that might be good for a standardization proposal need to be tested in
real-world applications before anyone knows that they will be useful.

Of course, some of gcc's C extensions are ill-considered and caused
problems, but one of the reasons we know how ill-considered they are
is that they were implemented and people tried to use them.  gcc has a
role to play as a deployment vehicle for language extensions.

The trouble is that it's very hard to kill an extension once people
are using it...

Andrew.