Simplifying druntime and phobos by getting rid of "shared static this()" blocks

[Steven Schveighoffer via Digitalmars-d]

On 5/24/17 12:40 PM, Andrei Alexandrescu wrote:
> On 5/24/17 4:49 PM, Steven Schveighoffer wrote:
>> On 5/23/17 3:47 PM, Andrei Alexandrescu wrote:
>>> https://github.com/dlang/phobos/pull/5421
>>>
>>> Looking forward to more in the same vein, please contribute! We have 25
>>> left in phobos and 12 in druntime. A big one will be making the GC
>>> lazily initialize itself. -- Andrei
>>
>> So every time I do:
>>
>> writeln(...)
>>
>> It has to go through a check to see if it's initialized? Using a
>> delegate?
>
> The delegate is not called in the steady state.

OK, I worry about inlineability as DMD has issues when you are using 
delegates sometimes. Unfortunately, I think the compiler isn't smart 
enough to realize that after one check of the boolean returns true, it 
could just access the File handle directly.

>
>> Has the performance of this been tested?
>
> Always a good idea. My test bed:
>
> void main()
> {
>     import std.stdio;
>     foreach (i; 0 .. 10_000_000) writeln("1234567890");
> }
>
> On my laptop using dmd, phobos master, best of 21 runs using "time test
>>/dev/null": 1.371 seconds.
>
> With initOnce: 1.469 seconds. Yuck!
>
> So I added double checking:
> https://github.com/dlang/phobos/pull/5421/commits/6ef3b5a6eacfe82239b7bbc4b0bc9f38adc6fe91
>
>
> With the double checking: 1.372 seconds. So back to sanity.
>
> Thanks for asking me to measure!

This is pretty decent. I still prefer the static ctor solution, but this 
is workable.

-Steve