Why Compiler Writers Accept instructions for the compiler as compiler switches rather than through the source code. What's wrong with providing options like "L/SUBSYSTEM:WINDOWS" through the source code?

On Sunday, 14 February 2021 at 07:56:43 UTC, Vinod K Chandran wrote:
> Why Compiler Writers Accept instructions for the compiler as compiler switches rather than through the source code. What's wrong with providing options like "L/SUBSYSTEM:WINDOWS" through the source code?

You are in luck, dmd does provide support for this...
https://dlang.org/spec/pragma.html#linkerDirective
... and it's wonderful, I wish all compilers followed suit.

https://dlang.org/spec/pragma.html#linkerDirective

On 2/13/2021 11:56 PM, Vinod K Chandran wrote:
> Why Compiler Writers Accept instructions for the compiler as compiler switches rather than through the source code. What's wrong with providing options like "L/SUBSYSTEM:WINDOWS" through the source code?

There are a couple pragmas that do it https://dlang.org/spec/pragma.html#linkerDirective but people generally prefer to do those with their build system.

On Sunday, 14 February 2021 at 08:41:15 UTC, kinke wrote:
> https://dlang.org/spec/pragma.html#linkerDirective

Thanks @kinke. Let me check.

On Sunday, 14 February 2021 at 08:59:32 UTC, Walter Bright wrote:
> On 2/13/2021 11:56 PM, Vinod K Chandran wrote:
>> Why Compiler Writers Accept instructions for the compiler as compiler switches rather than through the source code. What's wrong with providing options like "L/SUBSYSTEM:WINDOWS" through the source code?
>
> There are a couple pragmas that do it https://dlang.org/spec/pragma.html#linkerDirective but people generally prefer to do those with their build system.

Thanks @ Walter Bright
So I can write like this --
pragma(linkerDirective, "L/SUBSYSTEM:WINDOWS")
Am i right ? If so, i would like to know more about like which compiler switches are allowed to use with pragmas.

On 2/14/2021 8:58 AM, Vinod K Chandran wrote:
> So I can write like this --
> pragma(linkerDirective, "L/SUBSYSTEM:WINDOWS")
> Am i right ?

yes

> If so, i would like to know more about like which compiler switches are allowed to use with pragmas.

https://dlang.org/spec/pragma.html

The linkerDirective, however, is for linker switches.

On Sunday, 14 February 2021 at 22:26:54 UTC, Walter Bright wrote:
> On 2/14/2021 8:58 AM, Vinod K Chandran wrote:
>
> yes
>
Thanks for the reply.

> https://dlang.org/spec/pragma.html
>
I had already read that page.

> The linkerDirective, however, is for linker switches.
>
I would like to know how compiler switches like "-i", "-j" are using in "pragma"

On Monday, 15 February 2021 at 07:32:06 UTC, Vinod K Chandran wrote:

>>
> I would like to know how compiler switches like "-i", "-j" are using in "pragma"

There is no pragma for those switches.

On Sunday, 14 February 2021 at 07:56:43 UTC, Vinod K Chandran wrote:
> Why Compiler Writers Accept instructions for the compiler as compiler switches rather than through the source code. What's wrong with providing options like "L/SUBSYSTEM:WINDOWS" through the source code?

I think rund [1] offers what you're looking for. Give it a try and let us know what you think!

[1]: https://github.com/dragon-lang/rund