Go patch committed: Implement //go:nowritebarrierrec

[Ian Lance Taylor <iant at golang dot org>]

The libgo runtime package uses special comments //go:nowritebarrier,
//go:nowritebarrierrec, and //go:yeswritebarrierrec to record whether
write barriers are permitted in a function or not.  The Go frontend
already implements //go:nowritebarrier, but it has been treating
//go:nowritebarrierrec as equivalent to //go:nowritebarrier.  The
//go:nowritebarrierrec comment means not only that the function itself
may not have any write barriers, but also that any functions that it
calls directly may not have any write barriers--unless the function
called is marked //go:yeswritebarrierrec.  This patch implements
support for these comments in the Go frontend.  Bootstrapped and ran
Go testsuite on x86_64-pc-linux-gnu.  Committed to mainline.

Ian

Attachment: patch.txt
Description: Text document