Re: C++ pushback

[Michael Buesch <mb@bu3sch.de>]

On Thursday 27 April 2006 07:37, you wrote:
> > If C++ doesn't work 
> > properly for a simple and clean example like struct list_head, why 
> > should we assume that it's going to work any better for more complicated 
> > examples in the rest of the kernel?  Whether or not some arbitrary 
> > function is inlined should be totally orthogonal to adding type-checking.
> 
> You misunderstood something. The struct list_head is indeed a perfect 
> type to be templatized with all members inlined. C++ works properly in 
> this case.

I am not sure, if you can relieably use the container_of() magic
in C++. Do you know?
I have a C++ linked list example here:
http://websvn.kde.org/trunk/extragear/security/pwmanager/pwmanager/libpwmanager/linkedlist.h?rev=421676&view=markup
It is very simple and in some points different from the kernel
linked lists. It has a separate "head" and "entry" class and it stores
a pointer to the entry (the kernel linked lists would use container_of()
instead)

> Nothing works by default. I did not say that static constructors are 
> advantageous. I said that it is easy for the kernel to make static 
> constructors working. Global variables should be deprecated anyway.

You are kidding. Must be...

> > Plus this would 
> > break things like static spinlock initialization.  How would you make 
> > this work sanely for this static declaration:
> > 
> > spinlock_t foo_lock = SPIN_LOCK_UNLOCKED;
> > 
> > Under C that turns into (depending on config options):
> > 
> > spinlock_t foo_lock = { .value = 0, .owner = NULL, (...) };
> 
> I would make it exactly like this:
> 	#define SPIN_LOCK_UNLOCKED (spinlock_t){0,-1,whatever}
> 	spinlock_t foo_lock=SPIN_LOCK_UNLOCKED;
> This is easy to change. The empty structures look far more painful.

The lack of named initializers is one of the main reasons (for me)
why C++ damn sucks. Hopefully they will include them in the
next C++ standard.

-- 
Greetings Michael.

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