implement __d_dso_init for AArch64

[WalterBright]

I wanted to use inline assembler for this, but I haven't written an inline assembler for AArch64 yet.

With this, we might be able to start attempting to compile druntime.

[dlang-bot]

Thanks for your pull request, @WalterBright!

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[WalterBright]

ping @thewilsonator @dkorpel

[ibuclaw]

I wanted to use inline assembler for this, but I haven't written an inline assembler for AArch64 yet.

Why inline assembler when the comments make it out to be trivial D code; and it is trivial D code that gdc+ldc have in their druntimes to implement this hook.

[WalterBright]

Good question! The reasons are:

• it's the only place that needs it
• the backend is not set up to reference symbols that delineate sections
• it's just a handful of lines of code

[ibuclaw]

Good question! The reasons are:

• it's the only place that needs it
• the backend is not set up to reference symbols that delineate sections
• it's just a handful of lines of code

Fair point, its true that gdc and ldc support @section("minfo") void* __start_minfo;, which is a bit of an advantage.

https://gcc.gnu.org/onlinedocs/gcc-15.1.0/gdc/Common-Attributes.html#index-section-function-attribute

[WalterBright]

Thanks for the link. I'm reluctant to add such things without a demand for them, and dso_init for Elf is the only place I know of that needs it.

[Herringway]

Thanks for the link. I'm reluctant to add such things without a demand for them, and dso_init for Elf is the only place I know of that needs it.

I find it quite useful when dealing with non-standard binary formats, but I can just use a more capable compiler backend for that.