Where is the arm-none-eabi target?

[kinke]

On Friday, 13 March 2020 at 21:47:02 UTC, IGotD- wrote:
> cd ldc/runtime/druntime/src (where your druntime is located).
> ldc2 -c --output-o -conf= -w -de -dip1000 
> -mtriple=arm-none-eabi -O3 -release -preview=fieldwise 
> -od=/tmp/objects -op core/atomic.d

Works fine for me, again with v1.20 on Windows, no warnings wrt. 
unknown section size (needs OS-specific compiler support for 
`synchronized`). I can only guess that you are using an older LDC 
version.