So what does that middle dot actually do before the function names? It doesn't seem to be mentioned in the linked documentation of the Plan 9 assembler, and if

So what does that middle dot actually do before the function names? It doesn't seem to be mentioned in the linked documentation of the Plan 9 assembler, and if I have to use a character that I can't easily type with my keyboard, I'd like to at least know what it actually does. :) Also, doesn't doing this limit your code to using gc toolchain (since the generic Go function has to get called from the arch-specific asm code which uses that Plan 9 dialect)? Does this mean that the Go standard library can't be compiled with gccgo for example?