[dev.regabi] all: merge master (ff0e93e) into dev.regabi

Conflicts:

- src/cmd/compile/internal/gc/walk.go

  gc/walk.go is changed in CL 290950 on the master branch but
  deleted in the dev.regabi branch and moved over to the walk
  package. This CL includes porting CL 290950 over to the new
  walk.

Merge List:

+ 2021-02-12 ff0e93ea31 doc/go1.16: note that package path elements beginning with '.' are disallowed
+ 2021-02-11 249da7ec02 CONTRIBUTORS: update for the Go 1.16 release
+ 2021-02-11 864d4f1c6b cmd/go: multiple small 'go help' fixes
+ 2021-02-11 26ceae85a8 spec: More precise wording in section on function calls.
+ 2021-02-11 930c2c9a68 cmd/go: reject embedded files that can't be packed into modules
+ 2021-02-11 e5b08e6d5c io/fs: allow backslash in ValidPath, reject in os.DirFS.Open
+ 2021-02-10 ed8079096f cmd/compile: mark concrete call of reflect.(*rtype).Method as REFLECTMETHOD
+ 2021-02-09 e9c9683597 cmd/go: suppress errors from 'go get -d' for packages that only conditionally exist
+ 2021-02-09 e0ac989cf3 archive/tar: detect out of bounds accesses in PAX records resulting from padded lengths
+ 2021-02-09 c9d6f45fec runtime/metrics: fix a couple of documentation typpos
+ 2021-02-09 cea4e21b52 io/fs: backslash is always a glob meta character
+ 2021-02-08 dc725bfb3c doc/go1.16: mention new vet check for asn1.Unmarshal

Change-Id: Ib28fffa7dfbff7f6cdbfaf4a304757fead7bbf19

1 files changed, 22 insertions, 8 deletions

diff --git a/src/cmd/go/alldocs.go b/src/cmd/go/alldocs.go
index da06e831ae..db3f281ef3 100644
--- a/src/cmd/go/alldocs.go
+++ b/src/cmd/go/alldocs.go
@@ -1808,7 +1808,7 @@
 // 		The directory where the go command will write
 // 		temporary source files, packages, and binaries.
 // 	GOVCS
-// 	  Lists version control commands that may be used with matching servers.
+// 		Lists version control commands that may be used with matching servers.
 // 		See 'go help vcs'.
 //
 // Environment variables for use with cgo:
@@ -2410,6 +2410,17 @@
 //
 // For a detailed reference on modules, see https://golang.org/ref/mod.
 //
+// By default, the go command may download modules from https://proxy.golang.org.
+// It may authenticate modules using the checksum database at
+// https://sum.golang.org. Both services are operated by the Go team at Google.
+// The privacy policies for these services are available at
+// https://proxy.golang.org/privacy and https://sum.golang.org/privacy,
+// respectively.
+//
+// The go command's download behavior may be configured using GOPROXY, GOSUMDB,
+// GOPRIVATE, and other environment variables. See 'go help environment'
+// and https://golang.org/ref/mod#private-module-privacy for more information.
+//
 //
 // Module authentication using go.sum
 //
@@ -2868,20 +2879,23 @@
 // legal reasons). Therefore, clients can still access public code served from
 // Bazaar, Fossil, or Subversion repositories by default, because those downloads
 // use the Go module mirror, which takes on the security risk of running the
-// version control commands, using a custom sandbox.
+// version control commands using a custom sandbox.
 //
 // The GOVCS variable can be used to change the allowed version control systems
 // for specific packages (identified by a module or import path).
-// The GOVCS variable applies both when using modules and when using GOPATH.
-// When using modules, the patterns match against the module path.
-// When using GOPATH, the patterns match against the import path
-// corresponding to the root of the version control repository.
+// The GOVCS variable applies when building package in both module-aware mode
+// and GOPATH mode. When using modules, the patterns match against the module path.
+// When using GOPATH, the patterns match against the import path corresponding to
+// the root of the version control repository.
 //
 // The general form of the GOVCS setting is a comma-separated list of
 // pattern:vcslist rules. The pattern is a glob pattern that must match
 // one or more leading elements of the module or import path. The vcslist
 // is a pipe-separated list of allowed version control commands, or "all"
-// to allow use of any known command, or "off" to allow nothing.
+// to allow use of any known command, or "off" to disallow all commands.
+// Note that if a module matches a pattern with vcslist "off", it may still be
+// downloaded if the origin server uses the "mod" scheme, which instructs the
+// go command to download the module using the GOPROXY protocol.
 // The earliest matching pattern in the list applies, even if later patterns
 // might also match.
 //
@@ -2889,7 +2903,7 @@
 //
 // 	GOVCS=github.com:git,evil.com:off,*:git|hg
 //
-// With this setting, code with an module or import path beginning with
+// With this setting, code with a module or import path beginning with
 // github.com/ can only use git; paths on evil.com cannot use any version
 // control command, and all other paths (* matches everything) can use
 // only git or hg.