Trying to use mold for linking whole FreeBSD base and kernel - stuck at i386 BTX linking...

[freebsd-nils-level1]

Hi,

in order to try out mold for linking all of FreeBSD base and kernel, I've patched the source code of mold:
elf/cmdline.cc: } else if (arg == "elf_i386" || arg == "elf_i386_fbsd") {
to recognize FreeBSD's "elf_i386_fbsd" target emulation as standard "elf_i386".

So far linking works well with some tuning of FreeBSD's make files, but now I am stuck at linking the i386 BTX located at FreeBSD's /usr/src/stand/i386/btx/btx. It builds a DOS executable (COM), so no ELF at all. And it uses a linker script:

/* Simplified linker script for the boot loaders. */

OUTPUT_FORMAT("elf32-i386-freebsd")
OUTPUT_ARCH(i386)
ENTRY(_start)
SECTIONS {
  . = ORG;
  .text : { *(.text .text.*) } =0xcccccccc      /* Pad with int3, if needed */
  .rodata : { *(.rodata .rodata.*) }
  .got : { *(.got) *(.igot) }
  .got.plt : { *(.got.plt) *(.igot.plt) }
  .data : { *(.data .data.*) }
  _edata = .; PROVIDE (edata = .);
  .bss : { *(.bss .bss.*) }
  _end = .; PROVIDE (end = .);
  /DISCARD/ : { *(.interp) }
}

I've tried to recreate that using "--section-order" args to mold, but:

"/usr/local/bin/mold" --eh-frame-hdr -dynamic-linker /libexec/ld-elf.so.1 --hash-style=both --enable-new-dtags -m elf_i386_fbsd -o btx.full -L/usr/lib32 --compress-debug-sections=zlib -e start --oformat=binary "--section-order==0x9000 .text .got .got.plt .data edata .bss .end" -N -S --build-id=none -zrelro --no-rosegment btx.o
mold: error: --section-order: missing section specification for .rel.dyn
mold: error: --section-order: missing section specification for .rel.plt
mold: error: --section-order: missing section specification for .plt
mold: error: --section-order: missing section specification for .plt.got
mold: error: --section-order: missing section specification for .dynsym
mold: error: --section-order: missing section specification for .dynstr
mold: error: --section-order: missing section specification for .eh_frame
mold: error: --section-order: missing section specification for .copyrel
mold: error: --section-order: missing section specification for .copyrel.rel.ro
mold: error: --section-order: missing section specification for .interp
mold: error: --section-order: missing section specification for .eh_frame_hdr
mold: error: --section-order: missing section specification for .hash
mold: error: --section-order: missing section specification for .gnu.hash
mold: error: --section-order: missing section specification for .gnu.version
mold: error: --section-order: missing section specification for .gnu.version_r
mold: error: --section-order: missing section specification for .note.package
mold: error: --section-order: missing section specification for .note.gnu.property

The original ld cmdline is:

 "/usr/bin/ld" --eh-frame-hdr -dynamic-linker /libexec/ld-elf.so.1 --hash-style=both --enable-new-dtags \
-m elf_i386_fbsd -o btx -L/usr/lib32 \
-e start --defsym ORG=0x9000 -T /usr/src/stand/i386/boot.ldscript \
-N -S --oformat binary --build-id=none -zrelro --no-rosegment btx.o

vs mold cmdline:

 "/usr/local/bin/mold" --eh-frame-hdr -dynamic-linker /libexec/ld-elf.so.1 --hash-style=both --enable-new-dtags \
-m elf_i386_fbsd -o btx.full -L/usr/lib32 \
--compress-debug-sections=zlib -e start --oformat=binary "--section-order==0x9000 .text .got .got.plt .data edata .bss .end" \
-N -S --build-id=none -zrelro --no-rosegment btx.o

Now I am stuck. Any help is very appreciated...

TIA and BR,
Nils