cmd/link: convert -I foo to -Wl,--dynamic-linker,foo when externally linking

Fixes #22446

Change-Id: Id5b3fbc9cd3a7d6c4bf4e28428b8cb6d45a9ca92
Reviewed-on: https://go-review.googlesource.com/c/go/+/310349
Run-TryBot: Michael Hudson-Doyle <[email protected]>
TryBot-Result: Go Bot <[email protected]>
Trust: Michael Knyszek <[email protected]>
Reviewed-by: Ian Lance Taylor <[email protected]>

Author: mwhudson

src/cmd/link/internal/ld/lib.go

@@ -1431,6 +1431,14 @@ func (ctxt *Link) hostlink() {
 		argv = append(argv, fmt.Sprintf("-Wl,-rpath,%s", rpath.val))
 	}
 
+	if *flagInterpreter != "" {
+		// Many linkers support both -I and the --dynamic-linker flags
+		// to set the ELF interpreter, but lld only supports
+		// --dynamic-linker so prefer that (ld on very old Solaris only
+		// supports -I but that seems less important).
+		argv = append(argv, fmt.Sprintf("-Wl,--dynamic-linker,%s", *flagInterpreter))
+	}
+
 	// Force global symbols to be exported for dlopen, etc.
 	if ctxt.IsELF {
 		argv = append(argv, "-rdynamic")