cmd/link: set alignment for carrier symbols

For carrier symbols like type.*, currently we don't set its
alignment. Normally it doesn't actually matter as we still align
the inner symbols. But in some cases it does make the symbol table
a bit weird, e.g. on darwin/arm64,

0000000000070000 s _runtime.types
0000000000070001 s _type.*

The address of the symbol _type.* is a bit weird. And the new
darwin linker from Xcode 14 beta doesn't like that (see issue
53372).

This CL aligns them.

Fixes #53372.

Change-Id: I1cb19dcf172e9a6bca248d85a7e54da76cbbc8a4
Reviewed-on: https://go-review.googlesource.com/c/go/+/411912
Reviewed-by: Than McIntosh <[email protected]>
Run-TryBot: Cherry Mui <[email protected]>
TryBot-Result: Gopher Robot <[email protected]>

Author: cherrymui

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

@@ -475,16 +475,19 @@ func (ctxt *Link) symtab(pcln *pclntab) []sym.SymKind {
 			s = ldr.CreateSymForUpdate("type.*", 0)
 			s.SetType(sym.STYPE)
 			s.SetSize(0)
+			s.SetAlign(int32(ctxt.Arch.PtrSize))
 			symtype = s.Sym()
 
 			s = ldr.CreateSymForUpdate("typerel.*", 0)
 			s.SetType(sym.STYPERELRO)
 			s.SetSize(0)
+			s.SetAlign(int32(ctxt.Arch.PtrSize))
 			symtyperel = s.Sym()
 		} else {
 			s = ldr.CreateSymForUpdate("type.*", 0)
 			s.SetType(sym.STYPE)
 			s.SetSize(0)
+			s.SetAlign(int32(ctxt.Arch.PtrSize))
 			symtype = s.Sym()
 			symtyperel = s.Sym()
 		}
@@ -496,6 +499,7 @@ func (ctxt *Link) symtab(pcln *pclntab) []sym.SymKind {
 		s := ldr.CreateSymForUpdate(name, 0)
 		s.SetType(t)
 		s.SetSize(0)
+		s.SetAlign(int32(ctxt.Arch.PtrSize))
 		s.SetLocal(true)
 		setCarrierSym(t, s.Sym())
 		return s.Sym()