cmd/link: pass -Wl,-z,relro to host linker in -buildmode=PIE

Fixes #15485

Change-Id: I8e9314be91db89873130b232b589a284822e6643
Reviewed-on: https://go-review.googlesource.com/22687
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

diff --git a/src/cmd/link/internal/ld/lib.go b/src/cmd/link/internal/ld/lib.go
index a193704eb0de9361cd7dd1bc3b5997fbb437553f..711945fbd1e24a10fe7b44beb01f9fc09dacfca5 100644 (file)
--- a/src/cmd/link/internal/ld/lib.go
+++ b/src/cmd/link/internal/ld/lib.go
@@ -1091,6 +1091,9 @@ func hostlink() {
                        argv = append(argv, "-Wl,-pagezero_size,4000000")
                }
        case BuildmodePIE:
+               if UseRelro() {
+                       argv = append(argv, "-Wl,-z,relro")
+               }
                argv = append(argv, "-pie")
        case BuildmodeCShared:
                if HEADTYPE == obj.Hdarwin {