On Thu, 29 May 2014 13:12:24 -0400, Walter Bright
<newshou...@digitalmars.com> wrote:
On 5/29/2014 6:11 AM, Steven Schveighoffer wrote:
struct X
{
int a;
int b = void; // also initialized to 0.
}
This is because X must blit an init for a, and it would be silly to go
through
the trouble of blitting X.init to a, but not b. Especially, for
instance, if you
had an array of X (you'd have to blit every other int!)
But it would not be silly for:
struct X {
int a;
int[100] b = void;
}
to only initialize X.a. The compiler is allowed to optimize that. And,
in fact, I wished for just this in Warp.
I don't disagree. I think the spec should not specify what happens, to
leave it open for future optimizations.
Has anyone ever considered making the compiler build an 'optimized'
init-blitting function instead of just defaulting to memcpy? In other
words, the compiler knows at compile time the layout and initialization
values of a struct. What about using the compiler and optimizer to create
the most optimized, no-runtime-variables function to blit memory? We
wouldn't even need compiler help, if we did it with RTInfo.
-Steve
