binutils-gdb/ld
H.J. Lu 50c95a739c x86: Propery check PC16 reloc overflow in 16-bit mode instructions
commit a7664973b2
Author: Jan Beulich <jbeulich@suse.com>
Date:   Mon Apr 26 10:41:35 2021 +0200

    x86: correct overflow checking for 16-bit PC-relative relocs

caused linker failure when building 16-bit program in a 32-bit ELF
container.  Update GNU_PROPERTY_X86_FEATURE_2_USED with

 #define GNU_PROPERTY_X86_FEATURE_2_CODE16 (1U << 12)

to indicate that 16-bit mode instructions are used in the input object:

https://groups.google.com/g/x86-64-abi/c/UvvXWeHIGMA

to indicate that 16-bit mode instructions are used in the object to
allow linker to properly perform relocation overflow check for 16-bit
PC-relative relocations in 16-bit mode instructions.

1. Update x86 assembler to always generate the GNU property note with
GNU_PROPERTY_X86_FEATURE_2_CODE16 for .code16 in ELF object.
2. Update i386 and x86-64 linkers to use 16-bit PC16 relocations if
input object is marked with GNU_PROPERTY_X86_FEATURE_2_CODE16.

bfd/

	PR ld/27905
	* elf32-i386.c: Include "libiberty.h".
	(elf_howto_table): Add 16-bit R_386_PC16 entry.
	(elf_i386_rtype_to_howto): Add a BFD argument.  Use 16-bit
	R_386_PC16 if input has 16-bit mode instructions.
	(elf_i386_info_to_howto_rel): Update elf_i386_rtype_to_howto
	call.
	(elf_i386_tls_transition): Likewise.
	(elf_i386_relocate_section): Likewise.
	* elf64-x86-64.c (x86_64_elf_howto_table): Add 16-bit
	R_X86_64_PC16 entry.
	(elf_x86_64_rtype_to_howto): Use 16-bit R_X86_64_PC16 if input
	has 16-bit mode instructions.
	* elfxx-x86.c (_bfd_x86_elf_parse_gnu_properties): Set
	elf_x86_has_code16 if relocatable input is marked with
	GNU_PROPERTY_X86_FEATURE_2_CODE16.
	* elfxx-x86.h (elf_x86_obj_tdata): Add has_code16.
	(elf_x86_has_code16): New.

binutils/

	PR ld/27905
	* readelf.c (decode_x86_feature_2): Support
	GNU_PROPERTY_X86_FEATURE_2_CODE16.

gas/

	PR ld/27905
	* config/tc-i386.c (set_code_flag): Update x86_feature_2_used
	with GNU_PROPERTY_X86_FEATURE_2_CODE16 for .code16 in ELF
	object.
	(set_16bit_gcc_code_flag): Likewise.
	(x86_cleanup): Always generate the GNU property note if
	x86_feature_2_used isn't 0.
	* testsuite/gas/i386/code16-2.d: New file.
	* testsuite/gas/i386/code16-2.s: Likewise.
	* testsuite/gas/i386/x86-64-code16-2.d: Likewise.
	* testsuite/gas/i386/i386.exp: Run code16-2 and x86-64-code16-2.

include/

	PR ld/27905
	* elf/common.h (GNU_PROPERTY_X86_FEATURE_2_CODE16): New.

ld/

	PR ld/27905
	* testsuite/ld-i386/code16.d: New file.
	* testsuite/ld-i386/code16.t: Likewise.
	* testsuite/ld-x86-64/code16.d: Likewise.
	* testsuite/ld-x86-64/code16.t: Likewise.
	* testsuite/ld-i386/i386.exp: Run code16.
	* testsuite/ld-x86-64/x86-64.exp: Likewise.
2021-05-26 12:13:24 -07:00
..
emulparams Use bool in ld 2021-03-31 10:49:23 +10:30
emultempl convert elf_link_hash macros to inline functions 2021-04-12 21:19:02 +09:30
po Remove arm-symbianelf 2021-02-09 23:36:16 +10:30
scripttempl PRU: Add alignment for resource table, and allow sizes of memory regions to be set from the command line. 2021-05-10 13:58:17 +01:00
testsuite x86: Propery check PC16 reloc overflow in 16-bit mode instructions 2021-05-26 12:13:24 -07:00
.gitignore
aclocal.m4
ChangeLog x86: Propery check PC16 reloc overflow in 16-bit mode instructions 2021-05-26 12:13:24 -07:00
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config.in ENABLE_CHECKING in bfd, opcodes, binutils, ld 2021-04-13 00:35:44 +09:30
configure ENABLE_CHECKING in bfd, opcodes, binutils, ld 2021-04-13 00:35:44 +09:30
configure.ac ENABLE_CHECKING in bfd, opcodes, binutils, ld 2021-04-13 00:35:44 +09:30
configure.host
configure.tgt Remove arm-symbianelf 2021-02-09 23:36:16 +10:30
deffile.h
deffilep.y
dep-in.sed
elf-hints-local.h Remove bfd_stdint.h 2021-03-31 10:49:23 +10:30
fdl.texi
gen-doc.texi
genscrba.sh
genscripts.sh
h8-doc.texi
ld.h C99 ld configury 2021-04-05 15:31:53 +09:30
ld.texi ld: Add -Bno-symbolic 2021-05-13 12:53:49 +09:30
ldbuildid.c Remove strneq macro and use startswith. 2021-04-01 15:00:56 +02:00
ldbuildid.h Use bool in ld 2021-03-31 10:49:23 +10:30
ldcref.c Use bool in ld 2021-03-31 10:49:23 +10:30
ldctor.c Use bool in ld 2021-03-31 10:49:23 +10:30
ldctor.h Use bool in ld 2021-03-31 10:49:23 +10:30
ldelf.c convert elf_link_hash macros to inline functions 2021-04-12 21:19:02 +09:30
ldelf.h Use bool in ld 2021-03-31 10:49:23 +10:30
ldelfgen.c When computing section link order for a relocateable link, ignore section sizes. 2021-05-07 10:57:47 +01:00
ldelfgen.h Use bool in ld 2021-03-31 10:49:23 +10:30
ldemul.c Use bool in ld 2021-03-31 10:49:23 +10:30
ldemul.h Use bool in ld 2021-03-31 10:49:23 +10:30
ldexp.c multiple definition warnings from script symbols 2021-05-07 16:25:40 +09:30
ldexp.h Use bool in ld 2021-03-31 10:49:23 +10:30
ldfile.c Use bool in ld 2021-03-31 10:49:23 +10:30
ldfile.h Use bool in ld 2021-03-31 10:49:23 +10:30
ldgram.y Use bool in ld 2021-03-31 10:49:23 +10:30
ldint.texi
ldlang.c PR27719, lang_mark_undefineds trashes memory 2021-04-12 11:57:03 +09:30
ldlang.h Use bool in ld 2021-03-31 10:49:23 +10:30
ldlex-wrapper.c
ldlex.h ld: Add -Bno-symbolic 2021-05-13 12:53:49 +09:30
ldlex.l ld --defsym 2021-02-02 01:27:12 +10:30
ldmain.c multiple definition warnings from script symbols 2021-05-07 16:25:40 +09:30
ldmain.h Use bool in ld 2021-03-31 10:49:23 +10:30
ldmisc.c Use bool in ld 2021-03-31 10:49:23 +10:30
ldmisc.h Use bool in ld 2021-03-31 10:49:23 +10:30
ldver.c
ldver.h
ldwrite.c Use bool in ld 2021-03-31 10:49:23 +10:30
ldwrite.h
lexsup.c ld: Add -Bno-symbolic 2021-05-13 12:53:49 +09:30
libdep_plugin.c PR27722, error: array subscript has type char 2021-04-13 16:14:20 +09:30
MAINTAINERS
Makefile.am Prevent libdel.dll.a from being installed on Windows based systems. 2021-05-11 11:06:53 +01:00
Makefile.in Prevent libdel.dll.a from being installed on Windows based systems. 2021-05-11 11:06:53 +01:00
mri.c Use bool in ld 2021-03-31 10:49:23 +10:30
mri.h
NEWS ld: Add -Bno-symbolic 2021-05-13 12:53:49 +09:30
pe-dll.c ld: warn about PE base relocations to sections above .reloc 2021-04-06 10:54:57 +02:00
pe-dll.h Use bool in ld 2021-03-31 10:49:23 +10:30
pep-dll.c
pep-dll.h Use bool in ld 2021-03-31 10:49:23 +10:30
plugin.c PR27719, lang_mark_undefineds trashes memory 2021-04-12 11:57:03 +09:30
plugin.h Use bool in ld 2021-03-31 10:49:23 +10:30
README
stamp-h.in
sysdep.h C99 ld configury 2021-04-05 15:31:53 +09:30
testplug2.c Use bool in ld 2021-03-31 10:49:23 +10:30
testplug3.c Use bool in ld 2021-03-31 10:49:23 +10:30
testplug4.c Use bool in ld 2021-03-31 10:49:23 +10:30
testplug.c Use bool in ld 2021-03-31 10:49:23 +10:30
TODO

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		README for LD

This is the GNU linker.  It is distributed with other "binary
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=======================

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===========================

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==============

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HP/UX 9.01 has a shell bug that causes the linker scripts to be
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- scanner input buffer overflow" error messages.  There are various
workarounds to this:
  * Build and install bash, and build with "make SHELL=bash".
  * Update to a version of HP/UX with a working shell (e.g., 9.05).
  * Replace "(. ${srcdir}/scripttempl/${SCRIPT_NAME}.sc)" in
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