question about mecca fiber with address sanitizer

[Calvin P]

I try use Mecca style fiber with address sanitizer, get this 
question:


1) Mecca fiber use switchTo, not like DRuntime use switchIn and 
switchOut
2) __sanitizer_start_switch_fiber need a pointer to the bottom of 
the destination stack and its size.


My question is when Mecca fiber switchTo into main thread, how to 
get the main thread stackBottom and stackSize,  there is a 
getStackBottom from https://wiki.dlang.org/LDC_inline_IR, but 
only work for windows. I need a solution for linux and macOS.

I appreciate for any kind tips for my problem.