cmd/link: always mark runtime.buildVersion and runtime.modinfo reachable

runtime.buildVersion and runtime.modinfo are referenced in the
.go.buildinfo section, therefore reachable. They should normally
be reachable from the runtime. Just make it explicit, in case.

Change-Id: I60ff3132e0bbb690f4a3cba8bb18735921fbe951
Reviewed-on: https://go-review.googlesource.com/c/go/+/261637
Trust: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>

diff --git a/src/cmd/link/internal/ld/deadcode.go b/src/cmd/link/internal/ld/deadcode.go
index 74d61fa49512ac3ac46e3445ad3aa3ece9916e60..d8813fa9361c67a3ec8668f1509a56ffe3c76480 100644 (file)
--- a/src/cmd/link/internal/ld/deadcode.go
+++ b/src/cmd/link/internal/ld/deadcode.go
@@ -62,6 +62,12 @@ func (d *deadcodePass) init() {
                        }
                }
                names = append(names, *flagEntrySymbol)
+               if !d.ctxt.linkShared && d.ctxt.BuildMode != BuildModePlugin {
+                       // runtime.buildVersion and runtime.modinfo are referenced in .go.buildinfo section
+                       // (see function buildinfo in data.go). They should normally be reachable from the
+                       // runtime. Just make it explicit, in case.
+                       names = append(names, "runtime.buildVersion", "runtime.modinfo")
+               }
                if d.ctxt.BuildMode == BuildModePlugin {
                        names = append(names, objabi.PathToPrefix(*flagPluginPath)+"..inittask", objabi.PathToPrefix(*flagPluginPath)+".main", "go.plugin.tabs")