[Bug go/86331] the gccgo's "go" tool looks like failing to invoke any sub go command

[ian at airs dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86331

--- Comment #10 from Ian Lance Taylor <ian at airs dot com> ---
Thanks.  The documentation for the syscall function say that it only sets errno
on failure, but I forgot about signal handlers.  That is definitely a problem. 
Since there is no generic way to detect whether a system call failed, this may
require libgo to provide assembly language versions of syscall.Syscall.