[dev.cmdgo] all: merge master (9eee0ed) into dev.cmdgo

Conflicts:

- src/cmd/go/internal/modload/init.go
- src/cmd/go/internal/modload/load.go

Merge List:

+ 2021-07-28 9eee0ed439 cmd/go: fix go.mod file name printed in error messages for replacements
+ 2021-07-28 b39e0f461c runtime: don't crash on nil pointers in checkptrAlignment
+ 2021-07-27 7cd10c1149 cmd/go: use .mod instead of .zip to determine if version has go.mod file
+ 2021-07-27 c8cf0f74e4 cmd/go: add missing flag in UsageLine
+ 2021-07-27 7ba8e796c9 testing: clarify T.Name returns a distinct name of the running test
+ 2021-07-27 33ff155970 go/types: preserve untyped constants on the RHS of a shift expression
+ 2021-07-26 840e583ff3 runtime: correct variable name in comment
+ 2021-07-26 bfbb288574 runtime: remove adjustTimers counter
+ 2021-07-26 9c81fd53b3 cmd/vet: add missing copyright header
+ 2021-07-26 ecaa6816bf doc: clarify non-nil zero length slice to array pointer conversion
+ 2021-07-26 1868f8296e crypto/x509: update iOS bundled roots to version 55188.120.1.0.1
+ 2021-07-25 849b791129 spec: use consistent capitalization for rune literal hex constants
+ 2021-07-23 0914646ab9 doc/1.17: fix two dead rfc links
+ 2021-07-22 052da5717e cmd/compile: do not change field offset in ABI analysis
+ 2021-07-22 798ec73519 runtime: don't clear timerModifiedEarliest if adjustTimers is 0
+ 2021-07-22 fdb45acd1f runtime: move mem profile sampling into m-acquired section
+ 2021-07-21 3e48c0381f reflect: add missing copyright header
+ 2021-07-21 48c88f1b1b reflect: add Value.CanConvert
+ 2021-07-20 9e26569293 cmd/go: don't add C compiler ID to hash for standard library
+ 2021-07-20 d568e6e075 runtime/debug: skip TestPanicOnFault on netbsd/arm
+ 2021-07-19 c8f4e6152d spec: correct example comment in Conversions from slice to array
+ 2021-07-19 1d91551b73 time: correct typo in documentation for UnixMicro
+ 2021-07-19 404127c30f cmd/compile: fix off-by-one error in traceback argument counting
+ 2021-07-19 6298cfe672 cmd/compile: fix typo in fatal message of builtinCall
+ 2021-07-19 49402bee36 cmd/{compile,link}: fix bug in map.zero handling
+ 2021-07-18 a66190ecee test/bench/go1: fix size for RegexpMatchMedium_32
+ 2021-07-18 650fc2117a text/scanner: use Go convention in Position doc comment
+ 2021-07-16 aa4e0f528e net/http:  correct capitalization in cancelTimeBody comment
+ 2021-07-15 0941dbca6a testing: clarify in docs that TestMain is advanced
+ 2021-07-15 69728ead87 cmd/go: update error messages in tests to match CL 332573
+ 2021-07-15 c1cc9f9c3d cmd/compile: fix lookup package of redeclared dot import symbol
+ 2021-07-15 21a04e3335 doc/go1.17: mention GOARCH=loong64
+ 2021-07-14 2b00a54baf go/build, runtime/internal/sys: reserve GOARCH=loong64
+ 2021-07-14 60ddf42b46 cmd/go: change link in error message from /wiki to /doc.
+ 2021-07-13 d8f348a589 cmd/go: remove a duplicated word from 'go help mod graph'
+ 2021-07-12 a98589711d crypto/tls: test key type when casting
+ 2021-07-12 cfbd73ba33 doc/go1.17: editing pass over the "Compiler" section
+ 2021-07-09 ab4085ce84 runtime/pprof: call runtime.GC twice in memory profile test
+ 2021-07-08 296ddf2a93 net: filter bad names from Lookup functions instead of hard failing
+ 2021-07-08 ce76298ee7 Update oudated comment
+ 2021-07-08 2ca44fe221 doc/go1.17: linkify time.UnixMilli and time.UnixMicro
+ 2021-07-07 5c59e11f5e cmd/compile: remove special-casing of blank in types.sconv{,2}
+ 2021-07-07 b003a8b1ae cmd/compile: optimize types.sconv
+ 2021-07-07 11f5df2d67 cmd/compile: extract pkgqual from symfmt
+ 2021-07-07 991fd381d5 cmd/go: don't lock .mod and .sum files for read in overlay
+ 2021-07-07 186a3bb4b0 cmd/go/internal/modfetch/codehost: skip hg tests if no hg binary is present
+ 2021-07-07 00c00558e1 cmd/go/internal/modload: remove unused functions
+ 2021-07-07 f264879f74 cmd/go/internal/modload: fix an apparent typo in the AutoRoot comment
+ 2021-07-07 c96833e5ba doc: remove stale comment about arm64 port

Change-Id: Ide5fb43a0fcb5d998386ed60dfd6ced241238a44

1 files changed, 8 insertions, 1 deletions

diff --git a/src/cmd/go/internal/modload/init.go b/src/cmd/go/internal/modload/init.go
index 00dfc8b2dc..a3337d6d23 100644
--- a/src/cmd/go/internal/modload/init.go
+++ b/src/cmd/go/internal/modload/init.go
@@ -191,7 +191,7 @@ type Root int
 const (
 	// AutoRoot is the default for most commands. modload.Init will look for
 	// a go.mod file in the current directory or any parent. If none is found,
-	// modules may be disabled (GO111MODULE=on) or commands may run in a
+	// modules may be disabled (GO111MODULE=auto) or commands may run in a
 	// limited module mode.
 	AutoRoot Root = iota
 
@@ -1364,6 +1364,13 @@ func commitRequirements(ctx context.Context, goVersion string, rs *Requirements)
 		}
 		return
 	}
+	gomod := ModFilePath()
+	if _, ok := fsys.OverlayPath(gomod); ok {
+		if dirty {
+			base.Fatalf("go: updates to go.mod needed, but go.mod is part of the overlay specified with -overlay")
+		}
+		return
+	}
 
 	new, err := modFile.Format()
 	if err != nil {