all: add //go:build lines to assembly files

Don't add them to files in vendor and cmd/vendor though. These will be
pulled in by updating the respective dependencies.

For #41184

Change-Id: Icc57458c9b3033c347124323f33084c85b224c70
Reviewed-on: https://go-review.googlesource.com/c/go/+/319389
Trust: Tobias Klauser <tobias.klauser@gmail.com>
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>

50 files changed, 52 insertions, 7 deletions

diff --git a/src/runtime/asm_mips64x.s b/src/runtime/asm_mips64x.s
index c3b57e472a..d4d2280105 100644
--- a/src/runtime/asm_mips64x.s
+++ b/src/runtime/asm_mips64x.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build mips64 || mips64le
 // +build mips64 mips64le
 
 #include "go_asm.h"
diff --git a/src/runtime/asm_mipsx.s b/src/runtime/asm_mipsx.s
index 1d828b03cf..ea7edf20cf 100644
--- a/src/runtime/asm_mipsx.s
+++ b/src/runtime/asm_mipsx.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build mips || mipsle
 // +build mips mipsle
 
 #include "go_asm.h"
diff --git a/src/runtime/asm_ppc64x.s b/src/runtime/asm_ppc64x.s
index 2c39b38912..942cc14f17 100644
--- a/src/runtime/asm_ppc64x.s
+++ b/src/runtime/asm_ppc64x.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build ppc64 || ppc64le
 // +build ppc64 ppc64le
 
 #include "go_asm.h"
diff --git a/src/runtime/atomic_mips64x.s b/src/runtime/atomic_mips64x.s
index 6f42412502..e2118e6a20 100644
--- a/src/runtime/atomic_mips64x.s
+++ b/src/runtime/atomic_mips64x.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build mips64 || mips64le
 // +build mips64 mips64le
 
 #include "textflag.h"
diff --git a/src/runtime/atomic_mipsx.s b/src/runtime/atomic_mipsx.s
index ed078a2d8a..1eacd273b4 100644
--- a/src/runtime/atomic_mipsx.s
+++ b/src/runtime/atomic_mipsx.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build mips || mipsle
 // +build mips mipsle
 
 #include "textflag.h"
diff --git a/src/runtime/atomic_ppc64x.s b/src/runtime/atomic_ppc64x.s
index 57f672f330..b63de2dbd3 100644
--- a/src/runtime/atomic_ppc64x.s
+++ b/src/runtime/atomic_ppc64x.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build ppc64 || ppc64le
 // +build ppc64 ppc64le
 
 #include "textflag.h"
diff --git a/src/runtime/cgo/asm_mips64x.s b/src/runtime/cgo/asm_mips64x.s
index e51cdf3d12..ba948071fa 100644
--- a/src/runtime/cgo/asm_mips64x.s
+++ b/src/runtime/cgo/asm_mips64x.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build mips64 || mips64le
 // +build mips64 mips64le
 
 #include "textflag.h"
diff --git a/src/runtime/cgo/asm_mipsx.s b/src/runtime/cgo/asm_mipsx.s
index 1127c8beb4..fd5d78ef97 100644
--- a/src/runtime/cgo/asm_mipsx.s
+++ b/src/runtime/cgo/asm_mipsx.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build mips || mipsle
 // +build mips mipsle
 
 #include "textflag.h"
diff --git a/src/runtime/cgo/asm_ppc64x.s b/src/runtime/cgo/asm_ppc64x.s
index f4efc1e67d..9dec8d04ce 100644
--- a/src/runtime/cgo/asm_ppc64x.s
+++ b/src/runtime/cgo/asm_ppc64x.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build ppc64 || ppc64le
 // +build ppc64 ppc64le
 
 #include "textflag.h"
diff --git a/src/runtime/cgo/asm_riscv64.s b/src/runtime/cgo/asm_riscv64.s
index b4ddbb020f..fcd1d36ca8 100644
--- a/src/runtime/cgo/asm_riscv64.s
+++ b/src/runtime/cgo/asm_riscv64.s
@@ -2,8 +2,6 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build riscv64
-
 #include "textflag.h"
 
 // Called by C code generated by cmd/cgo.
diff --git a/src/runtime/duff_mips64x.s b/src/runtime/duff_mips64x.s
index c4e04ccc9d..a897d7fd9b 100644
--- a/src/runtime/duff_mips64x.s
+++ b/src/runtime/duff_mips64x.s
@@ -2,6 +2,7 @@
 // Run go generate from src/runtime to update.
 // See mkduff.go for comments.
 
+//go:build mips64 || mips64le
 // +build mips64 mips64le
 
 #include "textflag.h"
diff --git a/src/runtime/duff_ppc64x.s b/src/runtime/duff_ppc64x.s
index d6b89ba940..d4e3b409d2 100644
--- a/src/runtime/duff_ppc64x.s
+++ b/src/runtime/duff_ppc64x.s
@@ -2,6 +2,7 @@
 // Run go generate from src/runtime to update.
 // See mkduff.go for comments.
 
+//go:build ppc64 || ppc64le
 // +build ppc64 ppc64le
 
 #include "textflag.h"
diff --git a/src/runtime/internal/atomic/atomic_mips64x.s b/src/runtime/internal/atomic/atomic_mips64x.s
index 2751c6f808..fba668f94a 100644
--- a/src/runtime/internal/atomic/atomic_mips64x.s
+++ b/src/runtime/internal/atomic/atomic_mips64x.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build mips64 || mips64le
 // +build mips64 mips64le
 
 #include "textflag.h"
diff --git a/src/runtime/internal/atomic/atomic_mipsx.s b/src/runtime/internal/atomic/atomic_mipsx.s
index 3f61321450..c0835d66ed 100644
--- a/src/runtime/internal/atomic/atomic_mipsx.s
+++ b/src/runtime/internal/atomic/atomic_mipsx.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build mips || mipsle
 // +build mips mipsle
 
 #include "textflag.h"
diff --git a/src/runtime/internal/atomic/atomic_ppc64x.s b/src/runtime/internal/atomic/atomic_ppc64x.s
index 37c8515d37..dca26cb334 100644
--- a/src/runtime/internal/atomic/atomic_ppc64x.s
+++ b/src/runtime/internal/atomic/atomic_ppc64x.s
@@ -2,11 +2,11 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build ppc64 || ppc64le
 // +build ppc64 ppc64le
 
 #include "textflag.h"
 
-
 // For more details about how various memory models are
 // enforced on POWER, the following paper provides more
 // details about how they enforce C/C++ like models. This
diff --git a/src/runtime/internal/atomic/sys_nonlinux_arm.s b/src/runtime/internal/atomic/sys_nonlinux_arm.s
index 57568b2238..04036ca970 100644
--- a/src/runtime/internal/atomic/sys_nonlinux_arm.s
+++ b/src/runtime/internal/atomic/sys_nonlinux_arm.s
@@ -2,7 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build !linux,arm
+//go:build !linux
+// +build !linux
 
 #include "textflag.h"
 
diff --git a/src/runtime/libfuzzer_amd64.s b/src/runtime/libfuzzer_amd64.s
index 890fde341b..13645fc7af 100644
--- a/src/runtime/libfuzzer_amd64.s
+++ b/src/runtime/libfuzzer_amd64.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build libfuzzer
 // +build libfuzzer
 
 #include "go_asm.h"
diff --git a/src/runtime/libfuzzer_arm64.s b/src/runtime/libfuzzer_arm64.s
index 121673e092..4ad8242804 100644
--- a/src/runtime/libfuzzer_arm64.s
+++ b/src/runtime/libfuzzer_arm64.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build libfuzzer
 // +build libfuzzer
 
 #include "go_asm.h"
diff --git a/src/runtime/memclr_386.s b/src/runtime/memclr_386.s
index d2ef17f7ce..046c344119 100644
--- a/src/runtime/memclr_386.s
+++ b/src/runtime/memclr_386.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build !plan9
 // +build !plan9
 
 #include "go_asm.h"
diff --git a/src/runtime/memclr_amd64.s b/src/runtime/memclr_amd64.s
index 5d2bebb901..a10f57bd8c 100644
--- a/src/runtime/memclr_amd64.s
+++ b/src/runtime/memclr_amd64.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build !plan9
 // +build !plan9
 
 #include "go_asm.h"
diff --git a/src/runtime/memclr_mips64x.s b/src/runtime/memclr_mips64x.s
index d7a3251e20..bc037013fe 100644
--- a/src/runtime/memclr_mips64x.s
+++ b/src/runtime/memclr_mips64x.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build mips64 || mips64le
 // +build mips64 mips64le
 
 #include "go_asm.h"
diff --git a/src/runtime/memclr_mipsx.s b/src/runtime/memclr_mipsx.s
index eb2a8a7219..3d21c3c414 100644
--- a/src/runtime/memclr_mipsx.s
+++ b/src/runtime/memclr_mipsx.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build mips || mipsle
 // +build mips mipsle
 
 #include "textflag.h"
diff --git a/src/runtime/memclr_ppc64x.s b/src/runtime/memclr_ppc64x.s
index 7512620894..65639322b2 100644
--- a/src/runtime/memclr_ppc64x.s
+++ b/src/runtime/memclr_ppc64x.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build ppc64 || ppc64le
 // +build ppc64 ppc64le
 
 #include "textflag.h"
diff --git a/src/runtime/memmove_386.s b/src/runtime/memmove_386.s
index d99546c633..1a43a1f724 100644
--- a/src/runtime/memmove_386.s
+++ b/src/runtime/memmove_386.s
@@ -23,6 +23,7 @@
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 // THE SOFTWARE.
 
+//go:build !plan9
 // +build !plan9
 
 #include "go_asm.h"
diff --git a/src/runtime/memmove_amd64.s b/src/runtime/memmove_amd64.s
index f1e3403596..24c6529f58 100644
--- a/src/runtime/memmove_amd64.s
+++ b/src/runtime/memmove_amd64.s
@@ -23,6 +23,7 @@
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 // THE SOFTWARE.
 
+//go:build !plan9
 // +build !plan9
 
 #include "go_asm.h"
diff --git a/src/runtime/memmove_mips64x.s b/src/runtime/memmove_mips64x.s
index 8a1b88afba..fef3c6be82 100644
--- a/src/runtime/memmove_mips64x.s
+++ b/src/runtime/memmove_mips64x.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build mips64 || mips64le
 // +build mips64 mips64le
 
 #include "textflag.h"
diff --git a/src/runtime/memmove_mipsx.s b/src/runtime/memmove_mipsx.s
index 6c86558f8d..cd02fc25c4 100644
--- a/src/runtime/memmove_mipsx.s
+++ b/src/runtime/memmove_mipsx.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build mips || mipsle
 // +build mips mipsle
 
 #include "textflag.h"
diff --git a/src/runtime/memmove_ppc64x.s b/src/runtime/memmove_ppc64x.s
index dbd835506f..fd16ad8129 100644
--- a/src/runtime/memmove_ppc64x.s
+++ b/src/runtime/memmove_ppc64x.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build ppc64 || ppc64le
 // +build ppc64 ppc64le
 
 #include "textflag.h"
diff --git a/src/runtime/mkduff.go b/src/runtime/mkduff.go
index 8632fe08a3..da191cc594 100644
--- a/src/runtime/mkduff.go
+++ b/src/runtime/mkduff.go
@@ -179,6 +179,7 @@ func copyARM64(w io.Writer) {
 
 func tagsPPC64x(w io.Writer) {
 	fmt.Fprintln(w)
+	fmt.Fprintln(w, "//go:build ppc64 || ppc64le")
 	fmt.Fprintln(w, "// +build ppc64 ppc64le")
 	fmt.Fprintln(w)
 }
@@ -202,6 +203,7 @@ func copyPPC64x(w io.Writer) {
 
 func tagsMIPS64x(w io.Writer) {
 	fmt.Fprintln(w)
+	fmt.Fprintln(w, "//go:build mips64 || mips64le")
 	fmt.Fprintln(w, "// +build mips64 mips64le")
 	fmt.Fprintln(w)
 }
diff --git a/src/runtime/mkpreempt.go b/src/runtime/mkpreempt.go
index 3a9e6cc478..6c980540f5 100644
--- a/src/runtime/mkpreempt.go
+++ b/src/runtime/mkpreempt.go
@@ -123,6 +123,7 @@ func header(arch string) {
 	fmt.Fprintf(out, "// Code generated by mkpreempt.go; DO NOT EDIT.\n\n")
 	if beLe[arch] {
 		base := arch[:len(arch)-1]
+		fmt.Fprintf(out, "//go:build %s || %sle\n", base, base)
 		fmt.Fprintf(out, "// +build %s %sle\n\n", base, base)
 	}
 	fmt.Fprintf(out, "#include \"go_asm.h\"\n")
diff --git a/src/runtime/msan_amd64.s b/src/runtime/msan_amd64.s
index 669e9ca73f..1bb57a3b7e 100644
--- a/src/runtime/msan_amd64.s
+++ b/src/runtime/msan_amd64.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build msan
 // +build msan
 
 #include "go_asm.h"
diff --git a/src/runtime/msan_arm64.s b/src/runtime/msan_arm64.s
index f19906cfc8..93ade8dd89 100644
--- a/src/runtime/msan_arm64.s
+++ b/src/runtime/msan_arm64.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build msan
 // +build msan
 
 #include "go_asm.h"
diff --git a/src/runtime/preempt_mips64x.s b/src/runtime/preempt_mips64x.s
index 0d0c157c36..b755425bc5 100644
--- a/src/runtime/preempt_mips64x.s
+++ b/src/runtime/preempt_mips64x.s
@@ -1,5 +1,6 @@
 // Code generated by mkpreempt.go; DO NOT EDIT.
 
+//go:build mips64 || mips64le
 // +build mips64 mips64le
 
 #include "go_asm.h"
diff --git a/src/runtime/preempt_mipsx.s b/src/runtime/preempt_mipsx.s
index 86d3a918d3..c1bff60859 100644
--- a/src/runtime/preempt_mipsx.s
+++ b/src/runtime/preempt_mipsx.s
@@ -1,5 +1,6 @@
 // Code generated by mkpreempt.go; DO NOT EDIT.
 
+//go:build mips || mipsle
 // +build mips mipsle
 
 #include "go_asm.h"
diff --git a/src/runtime/preempt_ppc64x.s b/src/runtime/preempt_ppc64x.s
index 90634386db..70bd91982b 100644
--- a/src/runtime/preempt_ppc64x.s
+++ b/src/runtime/preempt_ppc64x.s
@@ -1,5 +1,6 @@
 // Code generated by mkpreempt.go; DO NOT EDIT.
 
+//go:build ppc64 || ppc64le
 // +build ppc64 ppc64le
 
 #include "go_asm.h"
diff --git a/src/runtime/race_amd64.s b/src/runtime/race_amd64.s
index 58a919efe8..8d4813eadd 100644
--- a/src/runtime/race_amd64.s
+++ b/src/runtime/race_amd64.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build race
 // +build race
 
 #include "go_asm.h"
diff --git a/src/runtime/race_arm64.s b/src/runtime/race_arm64.s
index 82e3caadc8..c6d5b91edc 100644
--- a/src/runtime/race_arm64.s
+++ b/src/runtime/race_arm64.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build race
 // +build race
 
 #include "go_asm.h"
diff --git a/src/runtime/race_ppc64le.s b/src/runtime/race_ppc64le.s
index 069e4d86dd..963e57099c 100644
--- a/src/runtime/race_ppc64le.s
+++ b/src/runtime/race_ppc64le.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build race
 // +build race
 
 #include "go_asm.h"
diff --git a/src/runtime/rt0_linux_mips64x.s b/src/runtime/rt0_linux_mips64x.s
index 55506755df..fabd8570b5 100644
--- a/src/runtime/rt0_linux_mips64x.s
+++ b/src/runtime/rt0_linux_mips64x.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build linux && (mips64 || mips64le)
 // +build linux
 // +build mips64 mips64le
 
diff --git a/src/runtime/rt0_linux_mipsx.s b/src/runtime/rt0_linux_mipsx.s
index 74b8f50b73..9f5842b51a 100644
--- a/src/runtime/rt0_linux_mipsx.s
+++ b/src/runtime/rt0_linux_mipsx.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build linux && (mips || mipsle)
 // +build linux
 // +build mips mipsle
 
diff --git a/src/runtime/sys_aix_ppc64.s b/src/runtime/sys_aix_ppc64.s
index a56d043f42..c171c191c0 100644
--- a/src/runtime/sys_aix_ppc64.s
+++ b/src/runtime/sys_aix_ppc64.s
@@ -2,9 +2,6 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build aix
-// +build ppc64 ppc64le
-
 //
 // System calls and other sys.stuff for ppc64, Aix
 //
diff --git a/src/runtime/sys_linux_mips64x.s b/src/runtime/sys_linux_mips64x.s
index 0206cb88bd..e18d291445 100644
--- a/src/runtime/sys_linux_mips64x.s
+++ b/src/runtime/sys_linux_mips64x.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build linux && (mips64 || mips64le)
 // +build linux
 // +build mips64 mips64le
 
diff --git a/src/runtime/sys_linux_mipsx.s b/src/runtime/sys_linux_mipsx.s
index d5317d3957..b3970be9cf 100644
--- a/src/runtime/sys_linux_mipsx.s
+++ b/src/runtime/sys_linux_mipsx.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build linux && (mips || mipsle)
 // +build linux
 // +build mips mipsle
 
diff --git a/src/runtime/sys_linux_ppc64x.s b/src/runtime/sys_linux_ppc64x.s
index 46387288d5..05b5916db4 100644
--- a/src/runtime/sys_linux_ppc64x.s
+++ b/src/runtime/sys_linux_ppc64x.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build linux && (ppc64 || ppc64le)
 // +build linux
 // +build ppc64 ppc64le
 
diff --git a/src/runtime/tls_arm.s b/src/runtime/tls_arm.s
index e42de8deb4..879caac9e1 100644
--- a/src/runtime/tls_arm.s
+++ b/src/runtime/tls_arm.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build !windows
 // +build !windows
 
 #include "go_asm.h"
diff --git a/src/runtime/tls_mips64x.s b/src/runtime/tls_mips64x.s
index 888c0efec6..779d64ba31 100644
--- a/src/runtime/tls_mips64x.s
+++ b/src/runtime/tls_mips64x.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build mips64 || mips64le
 // +build mips64 mips64le
 
 #include "go_asm.h"
diff --git a/src/runtime/tls_mipsx.s b/src/runtime/tls_mipsx.s
index d2ffcd954c..ada8d06a9e 100644
--- a/src/runtime/tls_mipsx.s
+++ b/src/runtime/tls_mipsx.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build mips || mipsle
 // +build mips mipsle
 
 #include "go_asm.h"
diff --git a/src/runtime/tls_ppc64x.s b/src/runtime/tls_ppc64x.s
index 25d796fcc6..7e935d0eb2 100644
--- a/src/runtime/tls_ppc64x.s
+++ b/src/runtime/tls_ppc64x.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build ppc64 || ppc64le
 // +build ppc64 ppc64le
 
 #include "go_asm.h"
diff --git a/src/runtime/wincallback.go b/src/runtime/wincallback.go
index 8411c98412..a7a787d8f6 100644
--- a/src/runtime/wincallback.go
+++ b/src/runtime/wincallback.go
@@ -22,7 +22,9 @@ func genasm386Amd64() {
 
 	buf.WriteString(`// Code generated by wincallback.go using 'go generate'. DO NOT EDIT.
 
+//go:build 386 || amd64
 // +build 386 amd64
+
 // runtime·callbackasm is called by external code to
 // execute Go implemented callback function. It is not
 // called from the start, instead runtime·compilecallback
diff --git a/src/runtime/zcallback_windows.s b/src/runtime/zcallback_windows.s
index 37ffb38aca..e451c2b9d0 100644
--- a/src/runtime/zcallback_windows.s
+++ b/src/runtime/zcallback_windows.s
@@ -1,6 +1,8 @@
 // Code generated by wincallback.go using 'go generate'. DO NOT EDIT.
 
+//go:build 386 || amd64
 // +build 386 amd64
+
 // runtime·callbackasm is called by external code to
 // execute Go implemented callback function. It is not
 // called from the start, instead runtime·compilecallback