cmd/link: use symbol-targeted relocation for initializers on Mach-O

Apple's new linker, ld-prime from Xcode 15 beta, when handling
initializers in __mod_init_func, drops the offset in the data,
resolving the relocation to the beginning of the section. The
latest version of ld-prime rejects non-zero addend. We need to use
symbol-targeted "external" relocations, so that it doesn't need
an addend and can be resolved correctly. This also works fine with
ld64.

Fixes #60694.
For #61229.

Change-Id: Ida2be6aa4c91bfcd142b755e2ec63aabfbbd77a6
Reviewed-on: https://go-review.googlesource.com/c/go/+/502616
Run-TryBot: Cherry Mui <cherryyz@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>

diff --git a/src/cmd/link/internal/amd64/asm.go b/src/cmd/link/internal/amd64/asm.go
index 7082c839eecaec075803ac1b8628f91506a91ea0..0c5486bf53c361568698306eadedc4df7ddfae20 100644 (file)
--- a/src/cmd/link/internal/amd64/asm.go
+++ b/src/cmd/link/internal/amd64/asm.go
@@ -469,7 +469,7 @@ func machoreloc1(arch *sys.Arch, out *ld.OutBuf, ldr *loader.Loader, s loader.Sy
        rs := r.Xsym
        rt := r.Type
 
-       if ldr.SymType(rs) == sym.SHOSTOBJ || rt == objabi.R_PCREL || rt == objabi.R_GOTPCREL || rt == objabi.R_CALL {
+       if rt == objabi.R_PCREL || rt == objabi.R_GOTPCREL || rt == objabi.R_CALL || ldr.SymType(rs) == sym.SHOSTOBJ || ldr.SymType(s) == sym.SINITARR {
                if ldr.SymDynid(rs) < 0 {
                        ldr.Errorf(s, "reloc %d (%s) to non-macho symbol %s type=%d (%s)", rt, sym.RelocName(arch, rt), ldr.SymName(rs), ldr.SymType(rs), ldr.SymType(rs))
                        return false

diff --git a/src/cmd/link/internal/arm64/asm.go b/src/cmd/link/internal/arm64/asm.go
index f2a2b32232149c9527805492692a00dcf25e6398..6e691dbe65cd11caba526e8305d4bddc995bbb74 100644 (file)
--- a/src/cmd/link/internal/arm64/asm.go
+++ b/src/cmd/link/internal/arm64/asm.go
@@ -577,10 +577,11 @@ func machoreloc1(arch *sys.Arch, out *ld.OutBuf, ldr *loader.Loader, s loader.Sy
                }
        }
 
-       if ldr.SymType(rs) == sym.SHOSTOBJ || rt == objabi.R_CALLARM64 ||
+       if rt == objabi.R_CALLARM64 ||
                rt == objabi.R_ARM64_PCREL_LDST8 || rt == objabi.R_ARM64_PCREL_LDST16 ||
                rt == objabi.R_ARM64_PCREL_LDST32 || rt == objabi.R_ARM64_PCREL_LDST64 ||
-               rt == objabi.R_ADDRARM64 || rt == objabi.R_ARM64_GOTPCREL {
+               rt == objabi.R_ADDRARM64 || rt == objabi.R_ARM64_GOTPCREL ||
+               ldr.SymType(rs) == sym.SHOSTOBJ || ldr.SymType(s) == sym.SINITARR {
                if ldr.SymDynid(rs) < 0 {
                        ldr.Errorf(s, "reloc %d (%s) to non-macho symbol %s type=%d (%s)", rt, sym.RelocName(arch, rt), ldr.SymName(rs), ldr.SymType(rs), ldr.SymType(rs))
                        return false

diff --git a/src/cmd/link/internal/ld/data.go b/src/cmd/link/internal/ld/data.go
index d651e2e346411f0839005c914e0e133964bfef02..21b2e9a9d4896b62de1e05128ccbda95ceae9f0d 100644 (file)
--- a/src/cmd/link/internal/ld/data.go
+++ b/src/cmd/link/internal/ld/data.go
@@ -368,7 +368,9 @@ func (st *relocSymState) relocsym(s loader.Sym, P []byte) {
                                                o = 0
                                        }
                                } else if target.IsDarwin() {
-                                       if ldr.SymType(rs) != sym.SHOSTOBJ {
+                                       if ldr.SymType(rs) != sym.SHOSTOBJ && ldr.SymType(s) != sym.SINITARR {
+                                               // ld-prime drops the offset in data for SINITARR. We need to use
+                                               // symbol-targeted relocation. See also machoreloc1.
                                                o += ldr.SymValue(rs)
                                        }
                                } else if target.IsWindows() {