cmd/link: always mark runtime.unreachableMethod symbol

In the deadcode path we mark runtime.unreachableMethod symbol,
which is a special symbol used for redirecting unreachable
methods. Currently this code is conditioned on not -linkshared.
This is wrong. It should be marked with -linkshared mode as well.

In fact, -linkshared should only affect the entry symbol. Change
the code accordingly.

Change-Id: I252abf850212a930f275589ef0035a43e52cb9cc
Reviewed-on: https://go-review.googlesource.com/c/go/+/319893
Trust: Cherry Mui <cherryyz@google.com>
Run-TryBot: Cherry Mui <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Jeremy Faller <jeremy@golang.org>

1 files changed, 20 insertions, 20 deletions

diff --git a/src/cmd/link/internal/ld/deadcode.go b/src/cmd/link/internal/ld/deadcode.go
index 1ed5598c99..416e5da398 100644
--- a/src/cmd/link/internal/ld/deadcode.go
+++ b/src/cmd/link/internal/ld/deadcode.go
@@ -65,26 +65,26 @@ func (d *deadcodePass) init() {
 			}
 		}
 		names = append(names, *flagEntrySymbol)
-		// runtime.unreachableMethod is a function that will throw if called.
-		// We redirect unreachable methods to it.
-		names = append(names, "runtime.unreachableMethod")
-		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")
-
-			// We don't keep the go.plugin.exports symbol,
-			// but we do keep the symbols it refers to.
-			exportsIdx := d.ldr.Lookup("go.plugin.exports", 0)
-			if exportsIdx != 0 {
-				relocs := d.ldr.Relocs(exportsIdx)
-				for i := 0; i < relocs.Count(); i++ {
-					d.mark(relocs.At(i).Sym(), 0)
-				}
+	}
+	// runtime.unreachableMethod is a function that will throw if called.
+	// We redirect unreachable methods to it.
+	names = append(names, "runtime.unreachableMethod")
+	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")
+
+		// We don't keep the go.plugin.exports symbol,
+		// but we do keep the symbols it refers to.
+		exportsIdx := d.ldr.Lookup("go.plugin.exports", 0)
+		if exportsIdx != 0 {
+			relocs := d.ldr.Relocs(exportsIdx)
+			for i := 0; i < relocs.Count(); i++ {
+				d.mark(relocs.At(i).Sym(), 0)
 			}
 		}
 	}