cmd/go: set the "generate" build tag in go generate, per design doc

And use it in two internal windows packages, so they don't show up in
"go list std" or binary releases on non-Windows platforms.

Fixes #31920

Change-Id: Iaa292b6015c9d7310dd677c9e296006440ba5e27
Reviewed-on: https://go-review.googlesource.com/c/go/+/175983
Reviewed-by: Rob Pike <r@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

diff --git a/src/cmd/go/alldocs.go b/src/cmd/go/alldocs.go
index 051b3daef9eaaeec42ba455e8adec1ed431eb1ca..0ea0bad9a91676e3c4e1027417427bc7a15a1ac9 100644 (file)
--- a/src/cmd/go/alldocs.go
+++ b/src/cmd/go/alldocs.go
@@ -525,7 +525,9 @@
 // they are treated as a single package. Within a package, generate processes the
 // source files in a package in file name order, one at a time. Within
 // a source file, generate runs generators in the order they appear
-// in the file, one at a time.
+// in the file, one at a time. The go generate tool also sets the build
+// tag "generate" so that files may be examined by go generate but ignored
+// during build.
 //
 // If any generator returns an error exit status, "go generate" skips
 // all further processing for that package.

diff --git a/src/cmd/go/internal/generate/generate.go b/src/cmd/go/internal/generate/generate.go
index 19597c7a3386b6754c24c8bb8b236f3c95bd5abf..f2ae80e5dc68f5e2764c07e6f2226fba743108ee 100644 (file)
--- a/src/cmd/go/internal/generate/generate.go
+++ b/src/cmd/go/internal/generate/generate.go
@@ -114,7 +114,9 @@ one at a time. If the command line lists .go files from a single directory,
 they are treated as a single package. Within a package, generate processes the
 source files in a package in file name order, one at a time. Within
 a source file, generate runs generators in the order they appear
-in the file, one at a time.
+in the file, one at a time. The go generate tool also sets the build
+tag "generate" so that files may be examined by go generate but ignored
+during build.
 
 If any generator returns an error exit status, "go generate" skips
 all further processing for that package.
@@ -161,6 +163,9 @@ func runGenerate(cmd *base.Command, args []string) {
                        log.Fatalf("generate: %s", err)
                }
        }
+
+       cfg.BuildContext.BuildTags = append(cfg.BuildContext.BuildTags, "generate")
+
        // Even if the arguments are .go files, this loop suffices.
        printed := false
        for _, pkg := range load.Packages(args) {

diff --git a/src/internal/syscall/windows/mksyscall.go b/src/internal/syscall/windows/mksyscall.go
index a8edafb3c3b5aec036e4f34ede3532ad8e57f373..0bf87dc95c272b0d70a8bad3c733744a2eac964d 100644 (file)
--- a/src/internal/syscall/windows/mksyscall.go
+++ b/src/internal/syscall/windows/mksyscall.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build generate
+
 package windows
 
 //go:generate go run $GOROOT/src/syscall/mksyscall_windows.go -output zsyscall_windows.go syscall_windows.go security_windows.go psapi_windows.go symlink_windows.go

diff --git a/src/internal/syscall/windows/registry/mksyscall.go b/src/internal/syscall/windows/registry/mksyscall.go
index 077215351ef5bcaf0f1b24475ffcbebd6ea33b8b..fa8e27e8ff69bb8dfb3323a09e1acbf8ecb4dbea 100644 (file)
--- a/src/internal/syscall/windows/registry/mksyscall.go
+++ b/src/internal/syscall/windows/registry/mksyscall.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build generate
+
 package registry
 
 //go:generate go run $GOROOT/src/syscall/mksyscall_windows.go -output zsyscall_windows.go syscall.go