On 8/1/2019 3:49 PM, Seb wrote:
> Now available on CodeCov: https://codecov.io/gh/dlang/dmd/tree/master/src/dmd/backend

This is the first time for a coverage report for the back end! It's better than I expected, but still not good.

On Thursday, 1 August 2019 at 20:24:12 UTC, Walter Bright wrote:
> and is reasonably in sync with DMD. However, having endured multiple grand reshufflings of the DMD source code, and having recently headed off yet another one, I'm not much in favor of it.

So D suffers and can't make any significant changes to the backend in order to accommodate an old dead project that isn't being actively developed?

On 8/1/2019 4:05 PM, Exil wrote:
> On Thursday, 1 August 2019 at 20:24:12 UTC, Walter Bright wrote:
>> and is reasonably in sync with DMD. However, having endured multiple grand reshufflings of the DMD source code, and having recently headed off yet another one, I'm not much in favor of it.
> 
> So D suffers and can't make any significant changes to the backend in order to accommodate an old dead project that isn't being actively developed?

In my not-so-humble experience, shuffling code about is too easy, usually an illusion of progress (look ma! I changed lots of lines of code!).

Refactoring to improve the design and flow of the code is much harder, usually requiring a thorough understanding of the code. Switching the backend to using CodeBuilder is an example of such.

On Thursday, 1 August 2019 at 23:54:28 UTC, Walter Bright wrote:
> On 8/1/2019 4:05 PM, Exil wrote:
>> On Thursday, 1 August 2019 at 20:24:12 UTC, Walter Bright wrote:
>>> and is reasonably in sync with DMD. However, having endured multiple grand reshufflings of the DMD source code, and having recently headed off yet another one, I'm not much in favor of it.
>> 
>> So D suffers and can't make any significant changes to the backend in order to accommodate an old dead project that isn't being actively developed?
>
> In my not-so-humble experience, shuffling code about is too easy, usually an illusion of progress (look ma! I changed lots of lines of code!).

Who said it was for "progress"? Don't paint it as something it isn't. It's usually about maintainability and readability. Something the backend lacks. Lack of comments, horrible naming convention, etc... With documentation like this:

    /*****************
     * Free code
     */
    void code_free(code *cstart)

> Refactoring to improve the design and flow of the code is much harder, usually requiring a thorough understanding of the code. Switching the backend to using CodeBuilder is an example of such.

There's more to it than that. I once had to refactor a monolithic class. It had dozens of functions that it really shouldn't have. I didn't write the code, someone else did and other developers over the years kept adding onto it until it got to the state it was in. It was first easier to -reshuffle- refactor the code into separate files to better understand how it works and to decouple everything. It made the code more readable and easier to understand, and from there to easily be redesigned into appropriate.

Kind of like how when you go from C -> D, rather than rewriting it in idiomatic D straight away, it is easier and reduces bugs to do a direct conversion from C to D. I think this is something you should be familiar with.