RISC-V: PR27566, Do not relax when data segment phase is exp_seg_relro_adjust.

[deliverable/binutils-gdb.git] / ld / emultempl / riscvelf.em

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fragment <<EOF

#include "ldmain.h"
#include "ldctor.h"
#include "elf/riscv.h"
#include "elfxx-riscv.h"

static void
riscv_elf_before_allocation (void)
{
  gld${EMULATION_NAME}_before_allocation ();

  if (link_info.discard == discard_sec_merge)
    link_info.discard = discard_l;

  if (!bfd_link_relocatable (&link_info))
    {
      /* We always need at least some relaxation to handle code alignment.  */
      if (RELAXATION_DISABLED_BY_USER)
	TARGET_ENABLE_RELAXATION;
      else
	ENABLE_RELAXATION;
    }

  link_info.relax_pass = 4;
}

static void
gld${EMULATION_NAME}_after_allocation (void)
{
  int need_layout = 0;

  /* Don't attempt to discard unused .eh_frame sections until the final link,
     as we can't reliably tell if they're used until after relaxation.  */
  if (!bfd_link_relocatable (&link_info))
    {
      need_layout = bfd_elf_discard_info (link_info.output_bfd, &link_info);
      if (need_layout < 0)
	{
	  einfo (_("%X%P: .eh_frame/.stab edit: %E\n"));
	  return;
	}
    }

  /* PR 27566, if the phase of data segment is exp_seg_relro_adjust,
     that means we are still adjusting the relro, and shouldn't do the
     relaxations at this stage.  Otherwise, we will get the symbol
     values beofore handling the relro, and may cause truncated fails
     when the relax range crossing the data segment.  One of the solution
     is to monitor the data segment phase while relaxing, to know whether
     the relro has been handled or not.

     I think we probably need to record more information about data
     segment or alignments in the future, to make sure it is safe
     to doing relaxations.  */
  enum phase_enum *phase = &(expld.dataseg.phase);
  bfd_elf${ELFSIZE}_riscv_set_data_segment_info (&link_info, (int *) phase);

  do
    {
      ldelf_map_segments (need_layout);
    }
  while (bfd_elf${ELFSIZE}_riscv_restart_relax_sections (&link_info));
}

/* This is a convenient point to tell BFD about target specific flags.
   After the output has been created, but before inputs are read.  */

static void
riscv_create_output_section_statements (void)
{
  /* See PR 22920 for an example of why this is necessary.  */
  if (strstr (bfd_get_target (link_info.output_bfd), "riscv") == NULL)
    {
      /* The RISC-V backend needs special fields in the output hash structure.
	 These will only be created if the output format is a RISC-V format,
	 hence we do not support linking and changing output formats at the
	 same time.  Use a link followed by objcopy to change output formats.  */
      einfo (_("%F%P: error: cannot change output format"
	       " whilst linking %s binaries\n"), "RISC-V");
      return;
    }
}

EOF

LDEMUL_BEFORE_ALLOCATION=riscv_elf_before_allocation
LDEMUL_AFTER_ALLOCATION=gld${EMULATION_NAME}_after_allocation
LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=riscv_create_output_section_statements