GDC 9 and ARM Cortex-M

[Timo Sintonen]

I am updating my toolset and libraries to GCC/GDC 9.1 release. 
First impression is that druntime needs more work than with 
previous versions. Many places to change and even compiler 
crashes when compiling some files.

Before I look further I want to ask if there has been any testing 
with this target (cross compiler linux->arm-eabi). Is it expected 
to work, not to work or not tested at all.