binutils-gdb/gas/config/obj-elf.h
H.J. Lu b7d0721677 ELF: Support the section flag 'o' in .section directive
As shown in

https://sourceware.org/bugzilla/show_bug.cgi?id=25490

--gc-sections will silently remove __patchable_function_entries section
and generate corrupt result.  This patch adds the section flag 'o' to
.section directive:

.section __patchable_function_entries,"awo",@progbits,foo
.section __patchable_function_entries,"awoG",@progbits,foo,foo,comdat
.section __patchable_function_entries,"awo",@progbits,bar,unique,4
.section __patchable_function_entries,"awoG",@progbits,foo,foo,comdat,unique,1

which specifies the symbol name which the section references.  Assmebler
will set its elf_linked_to_section to a local section where the symbol
is defined.

Linker is updated to call mark_hook if gc_mark of any of its linked-to
sections is set after all sections, except for backend specific ones,
have been garbage collected.

bfd/

	PR gas/25381
	* bfd-in2.h: Regenerated.
	* elflink.c (_bfd_elf_gc_mark_extra_sections): Call mark_hook
	on section if gc_mark of any of its linked-to sections is set
	and don't set gc_mark again.
	* section.c (asection): Add linked_to_symbol_name to map_head
	union.

gas/

	PR gas/25381
	* config/obj-elf.c (get_section): Also check
	linked_to_symbol_name.
	(obj_elf_change_section): Also set map_head.linked_to_symbol_name.
	(obj_elf_parse_section_letters): Handle the 'o' flag.
	(build_group_lists): Renamed to ...
	(build_additional_section_info): This.  Set elf_linked_to_section
	from map_head.linked_to_symbol_name.
	(elf_adjust_symtab): Updated.
	* config/obj-elf.h (elf_section_match): Add linked_to_symbol_name.
	* doc/as.texi: Document the 'o' flag.
	* testsuite/gas/elf/elf.exp: Run PR gas/25381 tests.
	* testsuite/gas/elf/section18.d: New file.
	* testsuite/gas/elf/section18.s: Likewise.
	* testsuite/gas/elf/section19.d: Likewise.
	* testsuite/gas/elf/section19.s: Likewise.
	* testsuite/gas/elf/section20.d: Likewise.
	* testsuite/gas/elf/section20.s: Likewise.
	* testsuite/gas/elf/section21.d: Likewise.
	* testsuite/gas/elf/section21.l: Likewise.
	* testsuite/gas/elf/section21.s: Likewise.

ld/

	PR ld/24526
	PR ld/25021
	PR ld/25490
	* testsuite/ld-elf/elf.exp: Run PR ld/25490 tests.
	* testsuite/ld-elf/pr24526.d: New file.
	* testsuite/ld-elf/pr24526.s: Likewise.
	* testsuite/ld-elf/pr25021.d: Likewise.
	* testsuite/ld-elf/pr25021.s: Likewise.
	* testsuite/ld-elf/pr25490-2-16.rd: Likewise.
	* testsuite/ld-elf/pr25490-2-32.rd: Likewise.
	* testsuite/ld-elf/pr25490-2-64.rd: Likewise.
	* testsuite/ld-elf/pr25490-2.s: Likewise.
	* testsuite/ld-elf/pr25490-3-16.rd: Likewise.
	* testsuite/ld-elf/pr25490-3-32.rd: Likewise.
	* testsuite/ld-elf/pr25490-3-64.rd: Likewise.
	* testsuite/ld-elf/pr25490-3.s: Likewise.
	* testsuite/ld-elf/pr25490-4-16.rd: Likewise.
	* testsuite/ld-elf/pr25490-4-32.rd: Likewise.
	* testsuite/ld-elf/pr25490-4-64.rd: Likewise.
	* testsuite/ld-elf/pr25490-4.s: Likewise.
	* testsuite/ld-elf/pr25490-5-16.rd: Likewise.
	* testsuite/ld-elf/pr25490-5-32.rd: Likewise.
	* testsuite/ld-elf/pr25490-5-64.rd: Likewise.
	* testsuite/ld-elf/pr25490-5.s: Likewise.
	* testsuite/ld-elf/pr25490-6-16.rd: Likewise.
	* testsuite/ld-elf/pr25490-6-32.rd: Likewise.
	* testsuite/ld-elf/pr25490-6-64.rd: Likewise.
	* testsuite/ld-elf/pr25490-6.s: Likewise.
2020-02-06 18:05:10 -08:00

267 lines
7.5 KiB
C

/* ELF object file format.
Copyright (C) 1992-2020 Free Software Foundation, Inc.
This file is part of GAS, the GNU Assembler.
GAS is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3, or (at your option)
any later version.
GAS is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with GAS; see the file COPYING. If not, write to the Free
Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
02110-1301, USA. */
/* HP PA-RISC support was contributed by the Center for Software Science
at the University of Utah. */
#ifndef _OBJ_ELF_H
#define _OBJ_ELF_H
#define OBJ_ELF 1
/* Note that all macros in this file should be wrapped in #ifndef, for
sake of obj-multi.h which includes this file. */
#ifndef OUTPUT_FLAVOR
#define OUTPUT_FLAVOR bfd_target_elf_flavour
#endif
#define BYTES_IN_WORD 4 /* for now */
#include "bfd/elf-bfd.h"
#include "targ-cpu.h"
#ifdef TC_ALPHA
#define ECOFF_DEBUGGING (alpha_flag_mdebug > 0)
extern int alpha_flag_mdebug;
#endif
/* For now, always set ECOFF_DEBUGGING for a MIPS target. */
#ifdef TC_MIPS
#define ECOFF_DEBUGGING mips_flag_mdebug
extern int mips_flag_mdebug;
#endif /* TC_MIPS */
#ifdef OBJ_MAYBE_ECOFF
#ifndef ECOFF_DEBUGGING
#define ECOFF_DEBUGGING 1
#endif
#endif
/* Additional information we keep for each symbol. */
struct elf_obj_sy
{
/* Whether the symbol has been marked as local. */
int local;
/* Use this to keep track of .size expressions that involve
differences that we can't compute yet. */
expressionS *size;
/* The name specified by the .symver directive. */
char *versioned_name;
#ifdef ECOFF_DEBUGGING
/* If we are generating ECOFF debugging information, we need some
additional fields for each symbol. */
struct efdr *ecoff_file;
struct localsym *ecoff_symbol;
valueT ecoff_extern_size;
#endif
};
/* Match section group name, the sh_info field and the section_id
field. */
struct elf_section_match
{
const char *group_name;
const char *linked_to_symbol_name;
unsigned int info;
unsigned int section_id;
flagword flags;
};
#define OBJ_SYMFIELD_TYPE struct elf_obj_sy
#ifndef FALSE
#define FALSE 0
#define TRUE !FALSE
#endif
#ifndef obj_begin
#define obj_begin() elf_begin ()
#endif
extern void elf_begin (void);
#ifndef LOCAL_LABEL_PREFIX
#define LOCAL_LABEL_PREFIX '.'
#endif
/* should be conditional on address size! */
#define elf_symbol(asymbol) ((elf_symbol_type *) (&(asymbol)->the_bfd))
#ifndef S_GET_SIZE
#define S_GET_SIZE(S) \
(elf_symbol (symbol_get_bfdsym (S))->internal_elf_sym.st_size)
#endif
#ifndef S_SET_SIZE
#define S_SET_SIZE(S,V) \
(elf_symbol (symbol_get_bfdsym (S))->internal_elf_sym.st_size = (V))
#endif
#ifndef S_GET_ALIGN
#define S_GET_ALIGN(S) \
(elf_symbol (symbol_get_bfdsym (S))->internal_elf_sym.st_value)
#endif
#ifndef S_SET_ALIGN
#define S_SET_ALIGN(S,V) \
(elf_symbol (symbol_get_bfdsym (S))->internal_elf_sym.st_value = (V))
#endif
int elf_s_get_other (symbolS *);
#ifndef S_GET_OTHER
#define S_GET_OTHER(S) (elf_s_get_other (S))
#endif
#ifndef S_SET_OTHER
#define S_SET_OTHER(S,V) \
(elf_symbol (symbol_get_bfdsym (S))->internal_elf_sym.st_other = (V))
#endif
extern asection *gdb_section;
#ifndef obj_frob_file
#define obj_frob_file elf_frob_file
#endif
extern void elf_frob_file (void);
#ifndef obj_frob_file_before_adjust
#define obj_frob_file_before_adjust elf_frob_file_before_adjust
#endif
extern void elf_frob_file_before_adjust (void);
#ifndef obj_frob_file_after_relocs
#define obj_frob_file_after_relocs elf_frob_file_after_relocs
#endif
extern void elf_frob_file_after_relocs (void);
/* If the target doesn't have special processing for labels, take care of
dwarf2 output at the object file level. */
#ifndef tc_frob_label
#include "dwarf2dbg.h"
#define obj_frob_label dwarf2_emit_label
#endif
#ifndef obj_app_file
#define obj_app_file elf_file_symbol
#endif
extern void elf_file_symbol (const char *, int);
extern void obj_elf_section_change_hook (void);
extern void obj_elf_section (int);
extern const char * obj_elf_section_name (void);
extern void obj_elf_previous (int);
extern void obj_elf_version (int);
extern void obj_elf_common (int);
extern void obj_elf_data (int);
extern void obj_elf_text (int);
extern void obj_elf_change_section
(const char *, unsigned int, bfd_vma, int, struct elf_section_match *,
int, int);
extern void obj_elf_vtable_inherit (int);
extern void obj_elf_vtable_entry (int);
extern struct fix * obj_elf_get_vtable_inherit (void);
extern struct fix * obj_elf_get_vtable_entry (void);
extern bfd_boolean obj_elf_seen_attribute
(int, unsigned int);
extern int obj_elf_vendor_attribute (int);
/* BFD wants to write the udata field, which is a no-no for the
predefined section symbols in bfd/section.c. They are read-only. */
#ifndef obj_sec_sym_ok_for_reloc
#define obj_sec_sym_ok_for_reloc(SEC) ((SEC)->owner != 0)
#endif
void elf_obj_read_begin_hook (void);
#ifndef obj_read_begin_hook
#define obj_read_begin_hook elf_obj_read_begin_hook
#endif
void elf_obj_symbol_new_hook (symbolS *);
#ifndef obj_symbol_new_hook
#define obj_symbol_new_hook elf_obj_symbol_new_hook
#endif
void elf_copy_symbol_attributes (symbolS *, symbolS *);
#ifndef OBJ_COPY_SYMBOL_ATTRIBUTES
#define OBJ_COPY_SYMBOL_ATTRIBUTES(DEST, SRC) \
(elf_copy_symbol_attributes (DEST, SRC))
#endif
void elf_adjust_symtab (void);
#ifndef obj_adjust_symtab
#define obj_adjust_symtab elf_adjust_symtab
#endif
#ifndef SEPARATE_STAB_SECTIONS
/* Avoid ifndef each separate macro setting by wrapping the whole of the
stab group on the assumption that whoever sets SEPARATE_STAB_SECTIONS
caters to ECOFF_DEBUGGING and the right setting of INIT_STAB_SECTIONS
and OBJ_PROCESS_STAB too, without needing the tweaks below. */
/* Stabs go in a separate section. */
#define SEPARATE_STAB_SECTIONS 1
/* We need 12 bytes at the start of the section to hold some initial
information. */
extern void obj_elf_init_stab_section (segT);
#define INIT_STAB_SECTION(seg) obj_elf_init_stab_section (seg)
#ifdef ECOFF_DEBUGGING
/* We smuggle stabs in ECOFF rather than using a separate section.
The Irix linker can not handle a separate stabs section. */
#undef SEPARATE_STAB_SECTIONS
#define SEPARATE_STAB_SECTIONS (!ECOFF_DEBUGGING)
#undef INIT_STAB_SECTION
#define INIT_STAB_SECTION(seg) \
((void) (ECOFF_DEBUGGING ? 0 : (obj_elf_init_stab_section (seg), 0)))
#undef OBJ_PROCESS_STAB
#define OBJ_PROCESS_STAB(seg, what, string, type, other, desc) \
if (ECOFF_DEBUGGING) \
ecoff_stab ((seg), (what), (string), (type), (other), (desc))
#endif /* ECOFF_DEBUGGING */
#endif /* SEPARATE_STAB_SECTIONS not defined. */
extern void elf_frob_symbol (symbolS *, int *);
#ifndef obj_frob_symbol
#define obj_frob_symbol(symp, punt) elf_frob_symbol (symp, &punt)
#endif
extern void elf_pop_insert (void);
#ifndef obj_pop_insert
#define obj_pop_insert() elf_pop_insert()
#endif
#ifndef OBJ_MAYBE_ELF
/* If OBJ_MAYBE_ELF then obj-multi.h will define obj_ecoff_set_ext. */
#define obj_ecoff_set_ext elf_ecoff_set_ext
struct ecoff_extr;
extern void elf_ecoff_set_ext (symbolS *, struct ecoff_extr *);
#endif
extern asection *elf_com_section_ptr;
extern symbolS * elf_common_parse (int ignore ATTRIBUTE_UNUSED, symbolS *symbolP,
addressT size);
#endif /* _OBJ_ELF_H */