freebsd-skq/stand/i386/boot.ldscript
dim aac336d446 Link stand/i386 components using a linker script
LLD 10.0.0 changed the behavior of the -Ttext option, so that using
-Ttext=0x0 now causes linking of the loaders to fail with:

ld: error: output file too large: 18446744073707016908 bytes

I reported this in https://bugs.llvm.org/show_bug.cgi?id=44715, and
initially reverted the upstream change in r357259 to work around it.

However, after some discussion with Fangrui Song in the upstream ticket,
I think we can classify this as an unfortunate interaction between using
-Ttext=0 in combination with --no-rosegment.  (We added the latter
in r332090, because btxld does not correctly handle input with more
than 2 PT_LOAD segments.)

Fangrui suggested to use a linker script instead, and Warner was already
attempting this in r305353, but had to revert it due to "crypto-using
boot problems" (not sure what those were :).

This review updates the stand/i386/boot.ldscript to handle more
sections, inserts some symbols like _edata and such that we use in
libsa, and also discards any .interp section.

It uses ORG which is defined on the linker command line using
--defsym ORG=value to set the start of all the sections.

Reviewed by:	imp
MFC after:	2 weeks
Differential Revision: https://reviews.freebsd.org/D23952
2020-03-04 21:01:22 +00:00

18 lines
498 B
Plaintext

/* $FreeBSD$ */
/* 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) }
}