I'm getting a ton of linker errors when building with LDC with the aarch64 release from here: https://github.com/ldc-developers/ldc/releases

Lib/Android/arm64-v8a/libphobos2-ldc.a(concurrency.o):(.data._D3std11concurrency12__ModuleInfoZ+0x20): undefined reference to `_D4core4sync9condition12__ModuleInfoZ'
Lib/Android/arm64-v8a/libphobos2-ldc.a(parallelism.o): In function `_D3std11parallelism13totalCPUsImplFNbNiNeZk':
parallelism.d:(.text._D3std11parallelism13totalCPUsImplFNbNiNeZk+0x20): undefined reference to `CPU_COUNT'
Lib/Android/arm64-v8a/libphobos2-ldc.a(parallelism.o): In function `_D3std11parallelism8TaskPool6__ctorMFNeZCQBnQBmQBc':
parallelism.d:(.text._D3std11parallelism8TaskPool6__ctorMFNeZCQBnQBmQBc+0x64): undefined reference to `CPU_COUNT'
Lib/Android/arm64-v8a/libphobos2-ldc.a(parallelism.o): In function `_D3std11parallelism8TaskPool6__ctorMFNemZCQBoQBnQBd':
parallelism.d:(.text._D3std11parallelism8TaskPool6__ctorMFNemZCQBoQBnQBd+0xc0): undefined reference to `_D4core4sync9condition9Condition7__ClassZ'
parallelism.d:(.text._D3std11parallelism8TaskPool6__ctorMFNemZCQBoQBnQBd+0xc4): undefined reference to `_D4core4sync9condition9Condition7__ClassZ'
parallelism.d:(.text._D3std11parallelism8TaskPool6__ctorMFNemZCQBoQBnQBd+0xd0): undefined reference to `_D4core4sync9condition9Condition6__vtblZ'
parallelism.d:(.text._D3std11parallelism8TaskPool6__ctorMFNemZCQBoQBnQBd+0xd4): undefined reference to `_D4core4sync9condition9Condition6__initZ'
parallelism.d:(.text._D3std11parallelism8TaskPool6__ctorMFNemZCQBoQBnQBd+0xd8): undefined reference to `_D4core4sync9condition9Condition6__vtblZ'
parallelism.d:(.text._D3std11parallelism8TaskPool6__ctorMFNemZCQBoQBnQBd+0xdc): undefined reference to `_D4core4sync9condition9Condition6__initZ'
parallelism.d:(.text._D3std11parallelism8TaskPool6__ctorMFNemZCQBoQBnQBd+0x108): undefined reference to `_D4core4sync9condition9Condition6__ctorMFNbNfCQBsQBq5mutex5MutexZCQCmQCkQCiQCb'
parallelism.d:(.text._D3std11parallelism8TaskPool6__ctorMFNemZCQBoQBnQBd+0x134): undefined reference to `_D4core4sync9condition9Condition6__ctorMFNbNfCQBsQBq5mutex5MutexZCQCmQCkQCiQCb'
Lib/Android/arm64-v8a/libphobos2-ldc.a(parallelism.o): In function `_D3std11parallelism__T27__lazilyInitializedConstantTykVki4294967295S_DQCqQCp13totalCPUsImplFNbNiNeZkZQDbFNaNbNdNiNfZyk':
parallelism.d:(.text._D3std11parallelism__T27__lazilyInitializedConstantTykVki4294967295S_DQCqQCp13totalCPUsImplFNbNiNeZkZQDbFNaNbNdNiNfZyk+0x60): undefined reference to `CPU_COUNT'
Lib/Android/arm64-v8a/libphobos2-ldc.a(parallelism.o): In function `_D3std11parallelism8taskPoolFNdNeZ9__lambda2FNfZCQBvQBu8TaskPool':
parallelism.d:(.text._D3std11parallelism8taskPoolFNdNeZ9__lambda2FNfZCQBvQBu8TaskPool+0xc0): undefined reference to `CPU_COUNT'
Lib/Android/arm64-v8a/libphobos2-ldc.a(parallelism.o): In function `_D3std11parallelism18defaultPoolThreadsFNdNeZk':
parallelism.d:(.text._D3std11parallelism18defaultPoolThreadsFNdNeZk+0x84): undefined reference to `CPU_COUNT'

A lot of unresolved references to just CPU_COUNT. The confusing part is that it has undefined referenced to parts of in core, which I am linking the druntime as well. Is anyone able to build for android?

On Wednesday, 16 February 2022 at 20:40:02 UTC, Fry wrote:

If you're linking manually, make sure that -ldruntime-ldc comes after -lphobos2-ldc, and that your druntime lib has been compiled for the appropriate arch. CPU_COUNT is a druntime symbol too.

On Thursday, 17 February 2022 at 01:17:51 UTC, kinke wrote:

Yes I tried changing the order, it seems like I am getting all unresolved symbols for D. Including _d_assert, but only when I use the --no-undefined flag. I have no idea why it is spitting out so many unresolved references.

I got it working, kind of. I just needed to use a different ndk version. There's a lot of problems with the NDK, the latest one doesn't appear to have the bfd linker anymore.

Does anyone know why the bfd linker is needed and why the gold linker doesn't work for the emulated TLS?

On Friday, 18 February 2022 at 16:28:56 UTC, Fry wrote:

It's required for LDC's custom TLS emulation for Android, see 1st point in https://wiki.dlang.org/Build_D_for_Android#Directions_for_future_work. lld supports custom linker scripts AFAIK, so that should get it to work as well (putting the two sections adjacent to each other). There's a runtime check making sure the executable has been linked as expected.