There is an updated pull request by ericonr against master on the void-packages repository

https://github.com/ericonr/void-packages ldc
https://github.com/void-linux/void-packages/pull/31062

ldc: update to 1.26.0.
Also move to llvm12.

@q66

It ends up underlinked, because when I try building corecollector with it I get:

```
Project version: 0.3.5
Error relocating /usr/lib/libdruntime-ldc-shared.so.96: unw_init_local: symbol not found
Error relocating /usr/lib/libdruntime-ldc-shared.so.96: unw_get_proc_name: symbol not found
Error relocating /usr/lib/libdruntime-ldc-shared.so.96: unw_step: symbol not found
Error relocating /usr/lib/libdruntime-ldc-shared.so.96: unw_getcontext: symbol not found
Error relocating /usr/lib/libdruntime-ldc-shared.so.96: unw_get_proc_info: symbol not found

meson.build:1:0: ERROR: Executables created by D compiler ldc2 are not runnable.
```

But running with `LD_PRELOAD=/usr/lib/libunwind.so.1` after installing `llvm-libunwind` makes meson not complain.

Alpine seems to be doing a trick to build with `libunwind` (https://git.alpinelinux.org/aports/tree/community/ldc/APKBUILD): `-DC_SYSTEM_LIBS="unwind;m;pthread;rt;dl"`, which we can probably just appropriate.

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A patch file from https://github.com/void-linux/void-packages/pull/31062.patch is attached