Commit Graph

155 Commits

Author SHA1 Message Date
Alan Modra
64029e9368 Separate header PT_LOAD for -z separate-code
This patch, along with previous patches in the series, supports
putting the ELF file header and program headers in a PT_LOAD without
sections.

Logic governing whether headers a loaded has changed a little:  The
primary reason to include headers is now the presence of
SIZEOF_HEADERS in a linker script.  However, to support scripts that
may have reserved space for headers by hand, we continue to add
headers whenever the first section address is past the end of headers
modulo page size.

include/
	* bfdlink.h (struct bfd_link_info): Add load_phdrs field.
bfd/
	* elf-nacl.c (nacl_modify_segment_map): Cope with header PT_LOAD
	lacking sections.
	* elf.c (_bfd_elf_map_sections_to_segments): Assume file and
	program headers are required when info->load_phdrs.  Reorganize
	code handling program headers.  Generate a mapping without
	sections just for file and program headers when -z separate-code
	would indicate they should be on a different page to the first
	section.
ld/
	* ldexp.c (fold_name <SIZEOF_HEADERS>): Set link_info.load_phdrs.
	* testsuite/ld-elf/loadaddr1.d: Pass -z noseparate-code.
	* testsuite/ld-elf/loadaddr2.d: Likewise.
	* testsuite/ld-i386/vxworks2.sd: Adjust expected output.
	* testsuite/ld-powerpc/vxworks2.sd: Likewise.
	* testsuite/ld-elf/overlay.d: Remove spu xfail.
	* testsuite/ld-spu/ovl.lnk: Don't use SIZEOF_HEADERS.
	* testsuite/ld-tic6x/dsbt-be.ld: Likewise.
	* testsuite/ld-tic6x/dsbt-inrange.ld: Likewise.
	* testsuite/ld-tic6x/dsbt-overflow.ld: Likewise.
	* testsuite/ld-tic6x/dsbt.ld: Likewise.
2018-10-08 20:26:08 +10:30
Maciej W. Rozycki
6057dc97e4 LD: Always make a SEGMENT_START expression section-relative
Fix an issue with the SEGMENT_START builtin function where its result is
absolute when taken from the default supplied, and section-relative when
taken from a `-T' command-line override.  This is against documentation,
inconsistent and unexpected, and with PIE executables gives an incorrect
result with the `__executable_start' symbol.

Make the result of SEGMENT_START always section-relative then.

	ld/
	* ldexp.c (fold_binary): Always make the result of SEGMENT_START
	section-relative.
	* testsuite/ld-scripts/segment-start.d: New test.
	* testsuite/ld-scripts/segment-start.ld: New test linker script.
	* testsuite/ld-scripts/segment-start.s: New test source.
	* testsuite/ld-scripts/script.exp: Run the new test.
2018-09-14 20:22:56 +01:00
Maciej W. Rozycki
a000f8817b LD: Avoid a division by zero page size with SEGMENT_START handling
Avoid a division by zero and thus a linker crash in SEGMENT_START script
builtin function handling, by not checking the value supplied with a
`-T' command-line override against the maximum page size if that has not
been set.

	ld/
	* ldexp.c (fold_binary): Check that `config.maxpagesize' is
	non-zero before using it as a divisor.
2018-09-14 20:22:56 +01:00
Alan Modra
3d9c8f6b3f Delay evaluation of alignment expressions in output sections
git commit 702d16713 broke expressions using CONSTANT(COMMONPAGESIZE)
in ALIGN or SUBALIGN of output section statements, because these
optional fields were evaluated at script parse time and the patch in
question delayed setting of config.commonpagesize.  The right thing to
do is keep the tree representation of those fields for later
evaluation.

	PR 23571
	* ldlang.h (section_alignment): Make it an expression tree.
	(subsection_alignment): Likewise.
	* ldlang.c (topower): Delete.
	(output_section_statement_newfunc): Adjust initialization.
	(init_os): Evaluate section_alignment.
	(lang_size_sections_1): Likewise.
	(size_input_section): Evaluate subsection_alignment.
	(lang_enter_output_section_statement): Don't evaluate here.
	(lang_new_phdr): Use exp_get_vma rather than exp_get_value_int.
	* ldexp.h (exp_get_value_int): Delete.
	(exp_get_power): Declare.
	* ldexp.c (exp_get_value_int): Delete.
	(exp_get_power): New function.
	* emultempl/pe.em (place_orphan): Build expression for section
	alignment.
	* emultempl/pep.em (place_orphan): Likewise.
	* testsuite/ld-scripts/pr23571.d,
	* testsuite/ld-scripts/pr23571.t: New test.
	* testsuite/ld-scripts/align.exp: Run it.
2018-08-26 22:45:59 +09:30
Maciej W. Rozycki
d5c928c053 LD: Export relative-from-absolute symbol marking to BFD
It is usually possible to tell absolute and ordinary symbols apart in
BFD throughout the link, by checking whether the section that owns the
symbol is absolute or not.

That however does not work for ordinary symbols defined in a linker
script outside an output section statement.  Initially such symbols are
entered into to the link hash as absolute symbols, owned by the absolute
section.  A flag is set in the internal linker expression defining such
symbols to tell the linker to convert them to section-relative ones in
the final phase of the link.  That flag is however not accessible to BFD
linker code, including BFD target code in particular.

Add a flag to the link hash then to copy the information held in the
linker expression.  Define a macro, `bfd_is_abs_symbol', for BFD code to
use where determining whether a symbol is absolute or ordinary is
required before the final link phase.

This macro will correctly identify the special `__ehdr_start' symbol as
ordinary throughout link, for example, even though early on it will be
assigned to the absolute section.  Of course this does not let BFD code
identify what the symbol's ultimate section will be before the final
link phase has converted this symbol (in `update_definedness').

	include/
	* bfdlink.h (bfd_link_hash_entry): Add `rel_from_abs' member.

	bfd/
	* linker.c (bfd_is_abs_symbol): New macro.
	* bfd-in2.h: Regenerate.

	ld/
	* ldexp.c (exp_fold_tree_1) <etree_assign, etree_provide>
	<etree_provided>: Copy expression's `rel_from_abs' flag to the
	link hash.
2018-07-17 20:04:53 +01:00
H.J. Lu
34a87bb07a ld: Hide symbols defined by HIDDEN/PROVIDE_HIDDEN
There should be no difference in output for symbols defined by HIDDEN
or PROVIDE_HIDDEN assignments whether they are explicitly marked as
hidden or not.  This patch adds a new BFD function, bfd_link_hide_symbol,
to hide symbols defined by HIDDEN and PROVIDE_HIDDEN assignments.

bfd

	PR ld/23201
	* aout-target.h (MY_bfd_link_hide_symbol): New.
	* aout-tic30.c (MY_bfd_link_hide_symbol): Likewise.
	* binary.c (binary_bfd_link_hide_symbol): Likewise.
	* coff-alpha.c (_bfd_ecoff_bfd_link_hide_symbol): Likewise.
	* coff-mips.c (_bfd_ecoff_bfd_link_hide_symbol): Likewise.
	* coff-rs6000.c (_bfd_xcoff_bfd_link_hide_symbol): Likewise.
	* coffcode.h (coff_bfd_link_hide_symbol): Likewise.
	* elf-bfd.h (_bfd_elf_link_hide_symbol): Likewise.
	* elfxx-target.h (bfd_elfNN_bfd_link_hide_symbol): Likewise.
	* i386msdos.c (msdos_bfd_link_hide_symbol): Likewise.
	* ihex.c (ihex_bfd_link_hide_symbol): Likewise.
	* libbfd-in.h (_bfd_nolink_bfd_link_hide_symbol): Likewise.
	* linker.c (_bfd_generic_link_hide_symbol): Likewise.
	(bfd_link_hide_symbol): Likewise.
	* mach-o-target.c (bfd_mach_o_bfd_link_hide_symbol): Likewise.
	* mmo.c (mmo_bfd_link_hide_symbol): Likewise.
	* pef.c (bfd_pef_bfd_link_hide_symbol): Likewise.
	* plugin.c (bfd_plugin_bfd_link_hide_symbol): Likewise.
	* ppcboot.c (ppcboot_bfd_link_hide_symbol): Likewise.
	* som.c (som_bfd_link_hide_symbol): Likewise.
	* srec.c (srec_bfd_link_hide_symbol): Likewise.
	* tekhex.c (tekhex_bfd_link_hide_symbol): Likewise.
	* vms-alpha.c (vms_bfd_link_hide_symbol): Likewise.
	(alpha_vms_bfd_link_hide_symbol): Likewise.
	* xsym.c (bfd_sym_bfd_link_hide_symbol): Likewise.
	* coff64-rs6000.c (rs6000_xcoff64_vec): Add
	_bfd_generic_link_hide_symbol.
	(rs6000_xcoff64_aix_vec): Likewise.
	* elflink.c (bfd_elf_record_link_assignment): Don't make forced
	local symbol dynamic.
	(_bfd_elf_link_hide_symbol): New function.
	* elfxx-x86.c (_bfd_x86_elf_link_symbol_references_local): Don't
	check root.ldscript_def.
	* targets.c (bfd_target): Add _bfd_link_hide_symbol.
	(BFD_JUMP_TABLE_LINK): Add NAME##_bfd_link_hide_symbol.
	* bfd-in2.h: Regenerated.
	* libbfd.h: Likewise.

ld/

	PR ld/23201
	* ldexp.c (exp_fold_tree_1): Call bfd_link_hide_symbol to hide
	a symbol.
	* testsuite/ld-elf/provide-hidden-dynabs.nd: Removed.
	* testsuite/ld-elf/provide-hidden-dynsec.nd: Likewise.
	* testsuite/ld-elf/provide-hidden.exp: Replace
	provide-hidden-dynsec.nd with provide-hidden-sec.nd and
	provide-hidden-dyn.nd.  Replace provide-hidden-dynabs.nd with
	provide-hidden-abs.nd and provide-hidden-dyn.nd.
	* testsuite/ld-i386/pr23189.d: Expect no dynamic relocation.
	* testsuite/ld-x86-64/pr23189.d: Likewise.
2018-05-21 20:39:30 -07:00
Alan Modra
df5f2391f7 ld error/warning messages
This patch standardizes messages in ld, to better conform to the GNU
coding standard.  Besides issues of capitalization and full-stops,
I've
- Split up help messages for target options, so that adding a new
  option does not mean loss of translation for all the others.
- Embedded tabs have been removed, since a user might have tab stops
  set at other than 8 char intervals.
- Added missing program name (%P).  ld isn't the compiler.
- Put %F and %X first (and removed %X if %F was present).  These can
  go anywhere, but look silly in the m%Fiddle of a message, and
  choosing "%P%F:" in some messages but "%F%P:" in others leads to the
  likelihood of duplication in ld.pot.  Besides, the colon belongs
  with %P.

	* emulparams/call_nop.sh, * emulparams/cet.sh,
	* emulparams/elf32mcore.sh, * emultempl/aarch64elf.em
	* emultempl/aix.em, * emultempl/alphaelf.em, * emultempl/armcoff.em,
	* emultempl/armelf.em, * emultempl/avrelf.em, * emultempl/beos.em,
	* emultempl/bfin.em, * emultempl/cr16elf.em, * emultempl/elf32.em,
	* emultempl/elf-generic.em, * emultempl/hppaelf.em,
	* emultempl/linux.em, * emultempl/lnk960.em,
	* emultempl/m68hc1xelf.em, * emultempl/m68kcoff.em,
	* emultempl/m68kelf.em, * emultempl/metagelf.em,
	* emultempl/mipself.em, * emultempl/mmix-elfnmmo.em,
	* emultempl/mmo.em, * emultempl/msp430.em, * emultempl/nds32elf.em,
	* emultempl/nios2elf.em, * emultempl/pe.em, * emultempl/pep.em,
	* emultempl/ppc32elf.em, * emultempl/ppc64elf.em,
	* emultempl/scoreelf.em, * emultempl/sh64elf.em,
	* emultempl/spuelf.em, * emultempl/sunos.em, * emultempl/tic6xdsbt.em,
	* emultempl/ticoff.em, * emultempl/v850elf.em, * emultempl/vms.em,
	* emultempl/vxworks.em, * emultempl/xtensaelf.em, * ldcref.c,
	* ldctor.c, * ldexp.c, * ldfile.c, * ldgram.y, * ldlang.c,
	* ldmain.c, * ldmisc.c, * ldwrite.c, * lexsup.c, * mri.c, * pe-dll.c,
	* plugin.c: Standardize error/warning messages.
	* testsuite/ld-arc/jli-overflow.err,
	* testsuite/ld-arm/cmse-implib-errors.out,
	* testsuite/ld-arm/cmse-new-earlier-later-implib.out,
	* testsuite/ld-arm/cmse-new-implib-not-sg-in-implib.out,
	* testsuite/ld-arm/cmse-new-wrong-implib.out,
	* testsuite/ld-arm/cmse-veneers-no-gnu_sgstubs.out,
	* testsuite/ld-arm/cmse-veneers-wrong-entryfct.out,
	* testsuite/ld-arm/vxworks1-static.d,
	* testsuite/ld-cris/tls-err-20x.d, * testsuite/ld-cris/tls-err-29.d,
	* testsuite/ld-cris/tls-err-31.d, * testsuite/ld-cris/tls-err-33.d,
	* testsuite/ld-cris/tls-err-35.d, * testsuite/ld-cris/tls-err-37.d,
	* testsuite/ld-cris/tls-err-39.d, * testsuite/ld-cris/tls-err-41.d,
	* testsuite/ld-cris/tls-err-43.d, * testsuite/ld-cris/tls-err-45.d,
	* testsuite/ld-cris/tls-err-47.d, * testsuite/ld-cris/tls-err-49.d,
	* testsuite/ld-cris/tls-err-51.d, * testsuite/ld-cris/tls-err-67.d,
	* testsuite/ld-elf/dwarf2.err, * testsuite/ld-elf/dwarf3.err,
	* testsuite/ld-elf/orphan-5.l, * testsuite/ld-elf/orphan-6.l,
	* testsuite/ld-i386/vxworks1-static.d,
	* testsuite/ld-mips-elf/bal-jalx-pic-micromips-n32.d,
	* testsuite/ld-mips-elf/bal-jalx-pic-micromips-n64.d,
	* testsuite/ld-mips-elf/bal-jalx-pic-micromips.d,
	* testsuite/ld-mips-elf/bal-jalx-pic-n32.d,
	* testsuite/ld-mips-elf/bal-jalx-pic-n64.d,
	* testsuite/ld-mips-elf/bal-jalx-pic.d,
	* testsuite/ld-mips-elf/jal-global-overflow-1.d,
	* testsuite/ld-mips-elf/jal-local-overflow-1.d,
	* testsuite/ld-mips-elf/mode-change-error-1.d,
	* testsuite/ld-mips-elf/unaligned-branch-2.d,
	* testsuite/ld-mips-elf/unaligned-branch-ignore-2.d,
	* testsuite/ld-mips-elf/unaligned-branch-ignore-micromips.d,
	* testsuite/ld-mips-elf/unaligned-branch-ignore-mips16.d,
	* testsuite/ld-mips-elf/unaligned-branch-ignore-r6-1.d,
	* testsuite/ld-mips-elf/unaligned-branch-micromips.d,
	* testsuite/ld-mips-elf/unaligned-branch-mips16.d,
	* testsuite/ld-mips-elf/unaligned-branch-r6-1.d,
	* testsuite/ld-mips-elf/unaligned-branch-r6-2.d,
	* testsuite/ld-mips-elf/unaligned-branch.d,
	* testsuite/ld-mips-elf/unaligned-jalx-1.d,
	* testsuite/ld-mips-elf/unaligned-jalx-3.d,
	* testsuite/ld-mips-elf/unaligned-jalx-addend-1.d,
	* testsuite/ld-mips-elf/unaligned-jalx-addend-3.d,
	* testsuite/ld-mips-elf/unaligned-jalx-addend-micromips-1.d,
	* testsuite/ld-mips-elf/unaligned-jalx-addend-mips16-1.d,
	* testsuite/ld-mips-elf/unaligned-jalx-micromips-1.d,
	* testsuite/ld-mips-elf/unaligned-jalx-mips16-1.d,
	* testsuite/ld-mips-elf/unaligned-jump-micromips.d,
	* testsuite/ld-mips-elf/unaligned-jump-mips16.d,
	* testsuite/ld-mips-elf/unaligned-jump.d,
	* testsuite/ld-mips-elf/unaligned-ldpc-1.d,
	* testsuite/ld-mips-elf/unaligned-lwpc-1.d,
	* testsuite/ld-mips-elf/undefined.d,
	* testsuite/ld-mips-elf/vxworks1-static.d,
	* testsuite/ld-mmix/bpo-20.d, * testsuite/ld-mmix/bpo-20m.d,
	* testsuite/ld-mmix/bpo-7.d, * testsuite/ld-mmix/bpo-7m.d,
	* testsuite/ld-mmix/bpo-8.d, * testsuite/ld-mmix/bpo-8m.d,
	* testsuite/ld-mmix/greg-17.d, * testsuite/ld-mmix/greg-18.d,
	* testsuite/ld-mmix/greg-8.d, * testsuite/ld-mmix/greg-9.d,
	* testsuite/ld-plugin/plugin-14.d, * testsuite/ld-plugin/plugin-15.d,
	* testsuite/ld-plugin/plugin-16.d, * testsuite/ld-plugin/plugin-20.d,
	* testsuite/ld-plugin/plugin-21.d, * testsuite/ld-plugin/plugin-22.d,
	* testsuite/ld-plugin/plugin-23.d, * testsuite/ld-plugin/plugin-6.d,
	* testsuite/ld-plugin/plugin-7.d, * testsuite/ld-plugin/plugin-8.d,
	* testsuite/ld-powerpc/aix-weak-3-32.d,
	* testsuite/ld-powerpc/aix-weak-3-64.d,
	* testsuite/ld-powerpc/vxworks1-static.d,
	* testsuite/ld-sh/vxworks1-static.d,
	* testsuite/ld-sparc/vxworks1-static.d,
	* testsuite/ld-undefined/undefined.exp,
	* testsuite/ld-x86-64/pie1.d: Update for changed errors and warnings.
	* testsuite/ld-elf/warn1.d, * testsuite/ld-elf/warn2.d: Correct regex.
2018-02-26 10:51:12 +10:30
Alan Modra
c1c8c1ef9a Use %pI, %pR, %pS, %pT in place of %I, %R, %S and %T.
bfd/
	* elf32-arm.c, * elf32-hppa.c, * elf32-lm32.c, * elf32-m32r.c,
	* elf32-metag.c, * elf32-nds32.c, * elf32-or1k.c, * elf32-ppc.c,
	* elf32-s390.c, * elf32-sh.c, * elf32-tic6x.c, * elf32-tilepro.c,
	* elf64-ppc.c, * elf64-s390.c, * elflink.c, * elfnn-aarch64.c,
	* elfnn-riscv.c, * elfxx-sparc.c, * elfxx-tilegx.c, * elfxx-x86.c,
	* reloc.c: Replace use of %R and %T in format strings passed to
	einfo and friends by %pR and %pT.
ld/
	* ldmisc.c (vfinfo) Handle %pI, %pR, %pS and %pT in place of
	%I, %R, %S and %T.
	* ldcref.c, * ldctor.c, * ldemul.c, * ldexp.c, * ldgram.y,
	* ldlang.c, * ldlex.l, * ldmain.c, * ldmisc.c, * pe-dll.c,
	* emultempl/sh64elf.em: Replace use of of %I, %R, %S and %T in
	format strings passed to einfo and friends by %pI, %pR, %pS and %pT.
2018-02-19 23:55:53 +10:30
Alan Modra
871b3ab29e Use %pA and %pB in messages rather than %A and %B
First step towards compiler verification of _bfd_error_handler
arguments, and better verification of translated messages.

bfd/
	* bfd.c (_bfd_doprnt, _bfd_doprnt_scan): Handle %pA and %pB in place
	of %A and %B.
	* aout-adobe.c: Update all messages using %A and %B.
	* aout-cris.c: Likewise.
	* aoutx.h: Likewise.
	* archive.c: Likewise.
	* binary.c: Likewise.
	* cache.c: Likewise.
	* coff-alpha.c: Likewise.
	* coff-arm.c: Likewise.
	* coff-i860.c: Likewise.
	* coff-mcore.c: Likewise.
	* coff-ppc.c: Likewise.
	* coff-rs6000.c: Likewise.
	* coff-sh.c: Likewise.
	* coff-tic4x.c: Likewise.
	* coff-tic54x.c: Likewise.
	* coff-tic80.c: Likewise.
	* coff64-rs6000.c: Likewise.
	* coffcode.h: Likewise.
	* coffgen.c: Likewise.
	* cofflink.c: Likewise.
	* coffswap.h: Likewise.
	* compress.c: Likewise.
	* cpu-arm.c: Likewise.
	* ecoff.c: Likewise.
	* elf-attrs.c: Likewise.
	* elf-eh-frame.c: Likewise.
	* elf-ifunc.c: Likewise.
	* elf-m10300.c: Likewise.
	* elf-properties.c: Likewise.
	* elf-s390-common.c: Likewise.
	* elf.c: Likewise.
	* elf32-arc.c: Likewise.
	* elf32-arm.c: Likewise.
	* elf32-avr.c: Likewise.
	* elf32-bfin.c: Likewise.
	* elf32-cr16.c: Likewise.
	* elf32-cr16c.c: Likewise.
	* elf32-cris.c: Likewise.
	* elf32-crx.c: Likewise.
	* elf32-d10v.c: Likewise.
	* elf32-d30v.c: Likewise.
	* elf32-epiphany.c: Likewise.
	* elf32-fr30.c: Likewise.
	* elf32-frv.c: Likewise.
	* elf32-gen.c: Likewise.
	* elf32-hppa.c: Likewise.
	* elf32-i370.c: Likewise.
	* elf32-i386.c: Likewise.
	* elf32-i960.c: Likewise.
	* elf32-ip2k.c: Likewise.
	* elf32-iq2000.c: Likewise.
	* elf32-lm32.c: Likewise.
	* elf32-m32c.c: Likewise.
	* elf32-m32r.c: Likewise.
	* elf32-m68hc11.c: Likewise.
	* elf32-m68hc12.c: Likewise.
	* elf32-m68hc1x.c: Likewise.
	* elf32-m68k.c: Likewise.
	* elf32-mcore.c: Likewise.
	* elf32-mep.c: Likewise.
	* elf32-metag.c: Likewise.
	* elf32-microblaze.c: Likewise.
	* elf32-moxie.c: Likewise.
	* elf32-msp430.c: Likewise.
	* elf32-mt.c: Likewise.
	* elf32-nds32.c: Likewise.
	* elf32-nios2.c: Likewise.
	* elf32-or1k.c: Likewise.
	* elf32-pj.c: Likewise.
	* elf32-ppc.c: Likewise.
	* elf32-rl78.c: Likewise.
	* elf32-rx.c: Likewise.
	* elf32-s390.c: Likewise.
	* elf32-score.c: Likewise.
	* elf32-score7.c: Likewise.
	* elf32-sh-symbian.c: Likewise.
	* elf32-sh.c: Likewise.
	* elf32-sh64.c: Likewise.
	* elf32-sparc.c: Likewise.
	* elf32-spu.c: Likewise.
	* elf32-tic6x.c: Likewise.
	* elf32-tilepro.c: Likewise.
	* elf32-v850.c: Likewise.
	* elf32-vax.c: Likewise.
	* elf32-visium.c: Likewise.
	* elf32-wasm32.c: Likewise.
	* elf32-xgate.c: Likewise.
	* elf32-xtensa.c: Likewise.
	* elf64-alpha.c: Likewise.
	* elf64-gen.c: Likewise.
	* elf64-hppa.c: Likewise.
	* elf64-ia64-vms.c: Likewise.
	* elf64-mmix.c: Likewise.
	* elf64-ppc.c: Likewise.
	* elf64-s390.c: Likewise.
	* elf64-sh64.c: Likewise.
	* elf64-sparc.c: Likewise.
	* elf64-x86-64.c: Likewise.
	* elfcode.h: Likewise.
	* elfcore.h: Likewise.
	* elflink.c: Likewise.
	* elfnn-aarch64.c: Likewise.
	* elfnn-ia64.c: Likewise.
	* elfnn-riscv.c: Likewise.
	* elfxx-mips.c: Likewise.
	* elfxx-sparc.c: Likewise.
	* elfxx-tilegx.c: Likewise.
	* elfxx-x86.c: Likewise.
	* hpux-core.c: Likewise.
	* ieee.c: Likewise.
	* ihex.c: Likewise.
	* libbfd.c: Likewise.
	* linker.c: Likewise.
	* mach-o.c: Likewise.
	* merge.c: Likewise.
	* mmo.c: Likewise.
	* oasys.c: Likewise.
	* pdp11.c: Likewise.
	* pe-mips.c: Likewise.
	* peXXigen.c: Likewise.
	* peicode.h: Likewise.
	* reloc.c: Likewise.
	* rs6000-core.c: Likewise.
	* srec.c: Likewise.
	* stabs.c: Likewise.
	* vms-alpha.c: Likewise.
	* xcofflink.c: Likewise.
ld/
	* ldmisc.c (vfinfo): Handle %pA and %pB in place of %A and %B.
	* ldcref.c: Update all messages using %A and %B.
	* ldexp.c: Likewise.
	* ldlang.c: Likewise.
	* ldmain.c: Likewise.
	* ldmisc.c: Likewise.
	* pe-dll.c: Likewise.
	* plugin.c: Likewise.
	* emultempl/beos.em: Likewise.
	* emultempl/cr16elf.em: Likewise.
	* emultempl/elf32.em: Likewise.
	* emultempl/m68kcoff.em: Likewise.
	* emultempl/m68kelf.em: Likewise.
	* emultempl/mmo.em: Likewise.
	* emultempl/nds32elf.em: Likewise.
	* emultempl/pe.em: Likewise.
	* emultempl/pep.em: Likewise.
	* emultempl/spuelf.em: Likewise.
	* emultempl/sunos.em: Likewise.
	* emultempl/xtensaelf.em: Likewise.
2018-02-19 23:55:53 +10:30
Simon Marchi
e99955cd8e Fix compile time warnings building the binutils with clang.
bfdI would like to fix instances of the following warning, when building
with clang with no special CFLAGS other than -g3 -O0.

/home/emaisin/src/binutils-gdb/bfd/elflink.c:5425:45: error: performing pointer arithmetic on a null pointer has undefined behavior [-Werror,-Wnull-pointer-arithmetic]
    return (struct elf_link_hash_entry *) 0 - 1;
           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ^

Replacing those with "(struct elf_link_hash_entry *) -1" gets rid of the
warning.  I wanted to check that it didn't change the resulting code, so
I tried to build this:

  $ cat test.c
  int *before()
  {
          return (int *) 0 - 1;
  }

  int *after()
  {
          return (int *) - 1;
  }

  $ gcc -c test.c -g
  $ objdump -d test.o

  test.o:     file format elf64-x86-64

  Disassembly of section .text:

  0000000000000000 <before>:
     0:   55                      push   %rbp
     1:   48 89 e5                mov    %rsp,%rbp
     4:   48 c7 c0 fc ff ff ff    mov    $0xfffffffffffffffc,%rax
     b:   5d                      pop    %rbp
     c:   c3                      retq

  000000000000000d <after>:
     d:   55                      push   %rbp
     e:   48 89 e5                mov    %rsp,%rbp
    11:   48 c7 c0 ff ff ff ff    mov    $0xffffffffffffffff,%rax
    18:   5d                      pop    %rbp
    19:   c3                      retq

This shows that the previous code doesn't actually return -1 as the
function documentation says, but the new one does, so it's kind of a
bugfix.

bfd	* elf64-ppc.c (ppc64_elf_archive_symbol_lookup): Avoid pointer
	arithmetic on NULL pointer.
	* elflink.c (_bfd_elf_archive_symbol_lookup,
	elf_link_add_archive_symbols): Likewise.

ld	* ldexp.c (fold_name, exp_fold_tree_1): Avoid pointer arithmetic
	on NULL pointer.
2018-02-01 13:21:41 +00:00
Andrew Burgess
65f14869fd ld: Remove unused expression state
Previous commit removed all uses of the defsym field within the linker
expression union.  This commit cleans up the now redundant state.

ld/ChangeLog:

	* ldexp.h (union etree_union): Remove defsym field.
	* ldexp.c (exp_assop): Remove defsym parameter, and use of defsym
	parameter.
	(exp_assign): Remove passing of defsym parameter.
	(exp_defsym): Likewise.
	(exp_provide): Likewise.
2018-01-11 17:35:35 +00:00
Andrew Burgess
eab62f2f01 ld: Fix issue where PROVIDE overrides defined symbol
In a linker script, a sequence like this:

  foo = ADDR (.some_section);
  bar = foo;
  PROVIDE (foo = 0);

will result in 'bar = ADDR (.some_section)' and 'foo = 0', which seems
like incorrect behaviour, foo is clearly defined elsewhere, and so the
PROVIDE should not trigger.

The problem is that an expression like this:

    foo = ADDR (.some_section);

can't be evaluated until a late phase of the linker, due to the need
for the section '.some_section' to have been placed, then the PROVIDE
was being marked as being used during an earlier phase.  At the end of
the link, both lines:

    foo = ADDR (.some_section);
    PROVIDE (foo = 0);

are active, and this causes the final value of 'foo' to be 0.

The solution proposed in this commit is that, during earlier phases of
the linker, when we see the expression 'foo = ADDR (.some_section);',
instead of ignoring the expression, we create a "fake" definition of
'foo'.  The existence of this "fake" definition prevents the PROVIDE
from being marked used, and during the final phase the real definition
of 'foo' will replace the "fake" definition.

The new test provide-6 covers the exact case described above.  The
provide-7 test is similar to the above, but using constant
expressions, this was never broken, but is added here to increase
coverage.

The provide-8 case also didn't fail before this commit, but I did
manage to break this case during development of this patch.  This case
was only covered by a mmix test before, so I've added this here to
increase coverage.

ld/ChangeLog:

	* ldexp.c (exp_fold_tree_1): Rework condition underwhich provide
	nodes are ignored in the tree walk, and move the location at which
	we change provide nodes into provided nodes.
	(exp_init_os): Add etree_provided.
	* testsuite/ld-scripts/provide-6.d: New file.
	* testsuite/ld-scripts/provide-6.t: New file.
	* testsuite/ld-scripts/provide-7.d: New file.
	* testsuite/ld-scripts/provide-7.t: New file.
	* testsuite/ld-scripts/provide-8.d: New file.
	* testsuite/ld-scripts/provide-8.t: New file.
2018-01-11 17:35:35 +00:00
Andrew Burgess
b3b9f8d3e9 ld: In map file use '=' in PROVIDE statements
Currently when recording a PROVIDE statement in a linker map file we
display something like:

    PROVIDE (SYMBOL, VALUE)

However, in a linker script we write these statements like this:

    PROVIDE (SYMBOL = VALUE);

This commit changes the output in the map file to be closer to linker
script format, the map file now contains:

    PROVIDE (SYMBOL = VALUE)

The ';' is still missing from the end, but map files are not intended
to be valid linker script input, so adding the ';' just seems like
clutter.

ld/ChangeLog:

	* ldexp.c (exp_print_tree): Use '=' instead of ',' when printing
	PROVIDE statements.
	* testsuite/ld-scripts/provide-4.map: Update expected output.
	* testsuite/ld-scripts/provide-5.map: Likewise.
2018-01-11 17:33:20 +00:00
Alan Modra
219d1afa89 Update year range in copyright notice of binutils files 2018-01-03 17:49:56 +10:30
Alan Modra
165f707ac8 PR22471, undefined reference to linker-defined symbols
This patch processes linker script assignment statements before ld
opens DT_NEEDED libraries, in order to define symbols like __bss_start
that might also be defined by a library, falsely triggering an error
about "DSO missing from command line".

The initial value won't be correct when assigning a symbol from dot,
and I make no attempt to handle all expressions.  For example, an
assignment like "_start_foo = ADDR (.foo)" isn't valid until sections
are laid out, so won't define _start_foo early.  What's here should be
enough for most common scripts, and hopefully won't perturb fragile
scripts.

bfd/
	PR 22471
	* elflink.c (_bfd_elf_merge_symbol): Allow weak symbols to override
	early passes over linker script symbols.
	* linker.c (_bfd_generic_link_add_one_symbol): Allow symbols to
	override early passes over linker script symbols.  Clear ldscript_def
	on symbol definitions.
ld/
	PR 22471
	* ldexp.c (struct definedness_hash_entry): Delete "by_script".  Make
	"iteration" an 8-bit field, and update mask in all uses.
	(definedness_newfunc): Don't init "by_script".
	(update_definedness): Test ldscript_def rather than by_script.
	(is_sym_value): Likewise.
	(fold_name <DEFINED>): Return a result for first phase.  Test
	ldscript_def.
	(fold_name <NAME>): Return a result for first phase.
	* ldlang.c (open_input_bfds): Process all assignments, not just
	defsym.
	(lang_process): Increment lang_statement_iteration before
	open_input_bfds.
	* testsuite/ld-mips-elf/tlsdyn-o32-1.d: Adjust for larger .dynsym.
	* testsuite/ld-mips-elf/tlsdyn-o32-1.got: Likewise.
	* testsuite/ld-mips-elf/tlsdyn-o32-2.d: Likewise.
	* testsuite/ld-mips-elf/tlsdyn-o32-2.got: Likewise.
	* testsuite/ld-mips-elf/tlsdyn-o32-3.d: Likewise.
	* testsuite/ld-mips-elf/tlsdyn-o32-3.got: Likewise.
2017-11-28 22:57:00 +10:30
Alan Modra
cd5b2babea Copying symbol type in ld script assignments
There is a call to update_definedness between code that evaluates an
assignment expression value and code that transfers symbol
attributes.  When script assignment expressions contain DEFINED, that
can mean the wrong symbol type is copied.  This patch tracks symbols
read during expression evaluation, rather than examining the
expression and re-evaluating conditionals.  Not only does this
simplify the code, it also means ld can now copy symbol types in more
complex expressions.

An unfortunate side effect of copying symbol type for more complex
expressions affects mmix, which uses
 PROVIDE (Main = DEFINED (Main) ? Main : (DEFINED (_start) ? _start : _start.));
in a default script.  So now _start or _start. symbol type may be
copied, losing the function type specially set up for Main.  This can
be avoided by making bfd_copy_link_hash_symbol_type do nothing for
mmix.

bfd/
	* elf64-mmix.c (bfd_elf64_bfd_copy_link_hash_symbol_type): Define.
ld/
	* ldexp.h (struct ldexp_control): Add "assign_src".
	* ldexp.c (fold_trinary): Save and restore assign_src around
	condition evaluation.
	(fold_name <NAME>): Set expld.assign_src.
	(try_copy_symbol_type): Delete.
	(exp_fold_tree_1): Set symbol type using expld.assign_src.
2017-11-28 22:56:59 +10:30
H.J. Lu
d7475e036f ld: Add fold_segment_align/fold_segment_relro_end/fold_segment_end
Extract DATA_SEGMENT_END/DATA_SEGMENT_ALIGN/DATA_SEGMENT_RELRO_END cases
for GNU_RELRO segment into separate functions so that they can also be
used for text-only LOAD segment.

	* ldexp.c (fold_unary): Extract the DATA_SEGMENT_END case to ...
	(fold_segment_end): New function.
	(fold_binary): Extract the DATA_SEGMENT_ALIGN case to ...
	(fold_segment_align): New function.
	(fold_binary): Extract the DATA_SEGMENT_RELRO_END case to ...
	(fold_segment_relro_end): New function.
2017-11-12 17:20:18 -08:00
H.J. Lu
0f99513f2a ld: Update phase_enum/relro_enum and add seg_align_type
Update GNU_RELRO date type so that they can also be used for text-only
LOAD segment.

	* ldexp.h (phase_enum): Rename exp_dataseg_none,
	exp_dataseg_align_seen, exp_dataseg_relro_seen,
	exp_dataseg_end_seen, exp_dataseg_relro_adjust,
	exp_dataseg_adjust and exp_dataseg_done to exp_seg_none,
	exp_seg_align_seen, exp_seg_relro_seen, exp_seg_end_seen,
	exp_seg_relro_adjust, exp_seg_adjust and exp_seg_done.
	(relro_enum): Rename exp_dataseg_relro_none,
	exp_dataseg_relro_start and exp_dataseg_relro_end to
	exp_seg_relro_none, exp_seg_relro_start and exp_seg_relro_end.
	(seg_align_type): New struct type.
	(ldexp_control): Use seg_align_type.
	* ldexp.c (fold_unary): Updated.
	(fold_binary): Likewise.
	* ldlang.c (strip_excluded_output_sections): Likewise.
	(lang_size_sections_1): Likewise.
	(lang_size_sections): Likewise.
2017-11-12 17:17:58 -08:00
Alan Modra
2571583aed Update year range in copyright notice of all files. 2017-01-02 14:08:56 +10:30
Alan Modra
4193bc588b try_copy_symbol_type node_class check
* ldexp.c (try_copy_symbol_type): Remove unnecessary check.
2016-12-03 20:54:57 +10:30
Alan Modra
f02cb05882 Always descend into output section statements in lang_do_assignments
See https://sourceware.org/ml/binutils/2016-07/msg00091.html
This patch stop --gc-sections elf_gc_sweep_symbol localizing symbols
that ought to remain global.

The difficulty with always descending into output section statements
is that symbols defined by the script in such statements don't have
a bfd section when lang_do_assignments runs early in the link process.
There are two approaches to curing this problem.  Either we can
create the bfd section early, or we can use a special section.  This
patch takes the latter approach and uses bfd_und_section.  (Creating
bfd sections early results in changed output section order, and thus
lots of testsuite failures.  You can't create all output sections
early to ensure proper ordering as KEEP then stops empty sections
from being stripped.)

The wrinkle with this approach is that some code that runs at
gc-sections time needs to be made aware of the odd defined symbols
using bfd_und_section.

bfd/
	* elf64-x86-64.c (elf_x86_64_convert_load_reloc): Handle symbols
	defined temporarily with bfd_und_section.
	* elflink.c (_bfd_elf_gc_keep): Don't set SEC_KEEP for bfd_und_section.
	* elfxx-mips.c (mips_elf_local_pic_function_p): Exclude defined
	symbols with bfd_und_section.
ld/
	* ldlang.c (lang_do_assignments_1): Descend into output section
	statements that do not yet have bfd sections.  Set symbol section
	temporarily for symbols defined in such statements to the undefined
	section.  Don't error on data or reloc statements until final phase.
	* ldexp.c (exp_fold_tree_1 <etree_assign>): Handle bfd_und_section
	in expld.section.
	* testsuite/ld-mmix/bpo-10.d: Adjust.
	* testsuite/ld-mmix/bpo-11.d: Adjust.
2016-10-11 18:13:04 +10:30
Alan Modra
769553e65f Fold arithmetic integer expressions fallout
* ldexp.c (MAX): Define.
	(exp_unop, exp_binop, exp_trinop): Alloc at least enough for
	etree_type.value.
2016-10-07 22:59:30 +10:30
Alan Modra
94b41882b0 ld expression section
Changes the result of ld expressions that were previously plain
numbers to be an absolute address, in the same circumstances where
numbers are treated as absolute addresses.

	* ld.texinfo (Expression Section): Update result of arithmetic
	expressions.
	* ldexp.c (arith_result_section): New function.
	(fold_binary): Use it.
2016-10-04 10:43:50 +10:30
Alan Modra
9ad39107ca Fold arithmetic integer expressions
Commit b751e639 regressed arm linux kernel builds, that have an
ASSERT (((__hyp_idmap_text_end - (__hyp_idmap_text_start
       			          & ~ (((0x1 << 0xc) - 0x1))))
         <= (0x1 << 0xc)), HYP init code too big or misaligned)

Due to some insanity in ld expression evaluation, the integer values
0x1 and 0xc above are treated as absolute addresses (ie. they have an
associated section, *ABS*, see exp_fold_tree_1 case etree_value) while
the expression (0x1 << 0xc) has a plain number result.  The left hand
side of the inequality happens to evaluate to a "negative" .text
section relative value.  Comparing a section relative value against an
absolute value works since the section relative value is first
converted to absolute.  Comparing a section relative value against a
number just compares the offsets, which fails since the "negative"
offset is really a very large positive number.

This patch works around the problem by folding integer expressions, so
the assert again becomes
ASSERT (((__hyp_idmap_text_end - (__hyp_idmap_text_start
       			          & 0xfffffffffffff000))
         <= 0x1000), HYP init code too big or misaligned)

	* ldexp.c (exp_value_fold): New function.
	(exp_unop, exp_binop, exp_trinop): Use it.
2016-10-04 10:41:26 +10:30
Alan Modra
b751e639fc Early expression evaluation
Folding a constant expression early can lead to loss of tokens, eg.
ABSOLUTE, that are significant in ld's horrible context sensitive
expression evaluation.  Also, MAXPAGESIZE and other "constants" may
not have taken values specified on the command line, leading to the
wrong value being cached.

	* ldexp.c (exp_unop, exp_binop, exp_trinop, exp_nameop): Don't
	fold expression.
	* testsuite/ld-elf/maxpage3b.d: Expect correct maxpagesize.
2016-07-20 10:55:45 +09:30
Thomas Preud'homme
7635954182 Add support for creating ELF import libraries
2016-07-15  Thomas Preud'homme  <thomas.preudhomme@arm.com>

bfd/
	* elf-bfd.h (elf_backend_filter_implib_symbols): Declare backend hook.
	(_bfd_elf_filter_global_symbols): Declare.
	* elf.c (_bfd_elf_filter_global_symbols): New function.
	* elflink.c (elf_filter_global_symbols): Likewise.
	(elf_output_implib): Likewise.
	(bfd_elf_final_link): Call above function, failing if it does.
	* elfxx-target.h (elf_backend_filter_implib_symbols): Define macro and
	default it to NULL.
	(elf_backend_copy_indirect_symbol): Fix spacing.
	(elf_backend_hide_symbol): Likewise.
	(elfNN_bed): Initialize elf_backend_filter_implib_symbols backend hook.

include/
	* bfdlink.h (struct bfd_link_info): Declare new ldscript_def and
	out_implib_bfd fields.

2016-07-15  Thomas Preud'homme  <thomas.preudhomme@arm.com>
	    Nick Clifton  <nickc@redhat.com>

ld/
	* emultempl/elf32.em (gld${EMULATION_NAME}_after_open): Open import
	library file for writing and initialize implib_bfd field of link_info
	structure.
	* emultempl/pe.em (pe_implib_filename): Remove variable declaration.
	(OPTION_IMPLIB_FILENAME): Remove macro definition.
	(gld${EMULATION_NAME}_add_options): Remove --out-implib option.
	(gld_${EMULATION_NAME}_list_options): Likewise.
	(gld${EMULATION_NAME}_handle_option): Likewise.
	(gld_${EMULATION_NAME}_finish): Use command_line.out_implib_filename
	instead of pe_implib_filename.
	* emultempl/pep.em (pep_implib_filename): Remove variable declaration.
	(OPTION_IMPLIB_FILENAME): Remove enumerator.
	(gld${EMULATION_NAME}_add_options): Remove --out-implib option.
	(gld_${EMULATION_NAME}_list_options): Likewise.
	(gld${EMULATION_NAME}_handle_option): Likewise.
	(gld_${EMULATION_NAME}_finish): Use command_line.out_implib_filename
	instead of pep_implib_filename.
	* ld.h (args_type): Declare new out_implib_filename field.
	* ld.texinfo (--out-implib): Move documentation to arch-independent
	part and rephrase to apply to ELF targets.
	* ldexp.c (exp_fold_tree_1): Set ldscript_def field to 1 for symbols
	defined in linker scripts.
	* ldlex.h (enum option_values): Declare new OPTION_OUT_IMPLIB
	enumerator.
	* lexsup.c (ld_options): Add entry for new --out-implib switch.
	(parse_args): Handle OPTION_OUT_IMPLIB case.
	* testsuite/ld-elf/elf.exp (Generate empty import library): New test.
	(Generate import library): Likewise.
	* testsuite/ld-elf/implib.s: Likewise.
	* testsuite/ld-elf/implib.rd: New file.
	* testsuite/ld-elf/empty-implib.out: Likewise
2016-07-15 17:50:48 +01:00
Jan Beulich
1753ed6811 ld: track linker-definedness of symbols
Keep "lineno" as zero while not processing any script, and use it being
zero to set the "linker_def" field to true.
2016-07-05 11:36:08 +02:00
Alan Modra
0aa7f5862e Formatting fixes.
* ldbuildid.c: Formatting.
	* ldcref.c: Formatting.
	* ldctor.c: Formatting.
	* ldemul.c: Formatting.
	* ldexp.c: Formatting.
	* ldfile.c: Formatting.
	* ldlang.c: Formatting.
	* ldmain.c: Formatting.
	* ldwrite.c: Formatting.
2016-06-14 13:25:21 +09:30
Alan Modra
6f2750feaf Copyright update for binutils 2016-01-01 23:00:01 +10:30
Alan Modra
321df0656c Evaluate __start_* and __stop_* symbol PROVIDE expressions early
Makes these symbols defined before bfd_elf_size_dynamic_sections, to
avoid horrible hacks elsewhere.  The exp_fold_tree undefweak change
is necessary to define undefweak symbols early too.  The comment was
wrong.  PROVIDE in fact defines undefweak symbols, via
bfd_elf_record_link_assignment.

	PR ld/19175
	* ldlang.c (lang_insert_orphan): Evaluate __start_* and __stop_*
	symbol PROVIDE expressions.
	* ldexp.c (exp_fold_tree_1 <etree_provide>): Define undefweak
	references.
2015-10-27 12:54:59 +10:30
Simon Dardis
1fb80d6d50 When evaluating a ternary operator in a linker script, copy the symbol flags.
* ld/ldexp.c: (try_copy_symbol_flags): New. Factored out from...
	(exp_fold_tree_1): Here.  Cope with ternary operator in
	assignments.  Use new helper.
2015-10-15 13:28:27 +01:00
Alan Modra
975f8a9e31 Delay converting linker script defined symbols from absolute
Giving linker script symbols defined outside of output sections a
section-relative value early, leads to them being used in expressions
as if they were defined inside an output section.  This can mean loss
of the section VMA, and wrong results.

ld/
	PR ld/18963
	* ldexp.h (struct ldexp_control): Add rel_from_abs.
	(ldexp_finalize_syms): Declare.
	* ldexp.c (new_rel_from_abs): Keep absolute for expressions
	outside of output section statements.  Set rel_from_abs.
	(make_abs, exp_fold_tree, exp_fold_tree_no_dot): Clear rel_from_abs.
	(struct definedness_hash_entry): Add final_sec, and comment.
	(update_definedness): Set final_sec.
	(set_sym_sections, ldexp_finalize_syms): New functions.
	* ldlang.c (lang_process): Call ldexp_finalize_syms.
ld/testsuite
	PR ld/18963
	* ld-scripts/pr18963.d,
	* ld-scripts/pr18963.t: New test.
	* ld-scripts/expr.exp: Run it.
	* ld-elf/provide-hidden-2.ld: Explicitly make "dot" absolute.
	* ld-mips-elf/gp-hidden.sd: Don't care about _gp section.
	* ld-mips-elf/no-shared-1-n32.d: Don't care about symbol shown at
	start of .data section.
	* ld-mips-elf/no-shared-1-n64.d: Likewise.
	* ld-mips-elf/no-shared-1-o32.d: Likewise.
2015-09-18 12:39:16 +09:30
Alan Modra
43417696fe PPC64: Allow .TOC. in linker script to override backend calculated value
bfd/
	* elf64-ppc.c (ppc64_elf_func_desc_adjust): Don't redefine .TOC.
	if already defined, and set linker_def.
	(ppc64_elf_set_toc): Use .TOC. value if defined other than by
	the backend.
ld/
	* ldexp.c (exp_fold_tree_1): Clear linker_def on symbol assignment.
2015-08-18 16:43:18 +09:30
H.J. Lu
995da1ffa7 Remove trailing spaces in ld 2015-08-12 04:46:43 -07:00
Alan Modra
e0a3af227e Revert ALIGN changes
Reverts a2c59f28 and e474ab13.  Since the unary form of ALIGN only
references "dot" implicitly, there isn't really a strong argument for
making ALIGN use a relative value when inside an output section.

	* ldexp.c (align_dot_val): Delete.
	(fold_unary <ALIGN_K, NEXT>): Revert 2015-07-10 change.
	(is_align_conditional): Revert 2015-07-20 change.
	(exp_fold_tree_1): Likewise, but keep expanded comment.
	* scripttempl/elf.sc (.ldata, .bss): Revert 2015-07-20 change.
	* ld.texinfo (<ALIGN>): Correct description.
2015-08-06 16:05:40 +09:30
Alan Modra
e474ab13ec ALIGN change affects standard scripts
a2c59f28 changed the way the unary ALIGN behaved inside output sections,
resulting in cris-elf testsuite regressions.  This patch pads out .bss
in the same manner as it was prior to the ALIGN change.

	* scripttempl/elf.sc (.ldata, .bss): Align absolute value of dot.
	* ldexp.c (is_align_conditional): Handle binary ALIGN.
	(exp_fold_tree_1): Move code setting SEC_KEEP for assignments to
	dot inside output sections.  Handle absolute expressions.
2015-07-20 14:29:21 +09:30
Alan Modra
a2c59f280d Make ALIGN(x) behave as ALIGN(.,x)
Inside output sections, ALIGN(.,x) uses a section-relative value for
dot.  The unary ALIGN always used the absolute value of dot.

	* ldexp.c (align_dot_val): New function.
	(fold_unary <ALIGN_K, NEXT>): Use it.
2015-07-10 20:08:55 +09:30
Alan Modra
0e5fabeb2c Rewrite relro adjusting code
The linker tries to put the end of the last section in the relro
segment exactly on a page boundary, because the relro segment itself
must end on a page boundary.  If for any reason this can't be done,
padding is inserted.  Since the end of the relro segment is typically
between .got and .got.plt, padding effectively increases the size of
the GOT.  This isn't nice for targets and code models with limited GOT
addressing.

The problem with the current code is that it doesn't cope very well
with aligned sections in the relro segment.  When making .got aligned
to a 256 byte boundary for PowerPC64, I found that often the initial
alignment attempt failed and the fallback attempt to be less than
adequate.  This is a particular problem for PowerPC64 since the
distance between .got and .plt affects the size of plt call stubs,
leading to "stubs don't match calculated size" errors.

So this rewrite takes a direct approach to calculating a new relro
base.  Starting from the last section in the segment, we calculate
where it must start to position its end on the boundary, or as near as
possible considering alignment requirements.  The new start then
becomes the goal for the previous section to end, and so on for all
sections.  This of course ignores the possibility that user scripts
will place . = ALIGN(xxx); in the relro segment, or provide section
address expressions.  In those cases we might fail, but the old code
probably did too, and a fallback is provided.

ld/
	* ldexp.h (struct ldexp_control): Delete dataseg.min_base.  Add
	data_seg.relro_offset.
	* ldexp.c (fold_binary <DATA_SEGMENT_ALIGN>): Don't set min_base.
	(fold_binary <DATA_SEGMENT_RELRO_END>): Do set relro_offset.
	* ldlang.c (lang_size_sections): Rewrite code adjusting relro
	segment base to line up last section on page boundary.
ld/testsuite/
	* ld-x86-64/pr18176.d: Update.
2015-04-22 23:19:59 +09:30
Alan Modra
6c1aca3e2d Start of relro segment adjustment
Adjusting the start of the relro segment in order to make it end
exactly on a page boundary runs into difficulties when sections in the
relro segment are aligned;  Adjusting the start by (next_page - end)
sometimes results in more than that adjustment occurring at the end,
overrunning the page boundary.  So when that occurs we try a new lower
start position by masking the adjusted start with the maximum section
alignment.  However, we didn't consider that this masked start address
may in fact be before the initial relro base, which is silly since
that can only increase padding at the relro end.

I've also moved some calculations closer to where they are used, and
comments closer to the relevant statements.

	* ldlang.c (lang_size_sections): When alignment of sections
	results in relro base adjustment being too large, don't go lower
	than the initial value.
	* ldexp.c (fold_binary <DATA_SEGMENT_RELRO_END>): Comment.
	* scripttempl/elf.sc (DATA_SEGMENT_ALIGN): Omit SEGMENT_SIZE
	alignment when SEGMENT_SIZE is the same as MAXPAGESIZE.
2015-04-01 19:37:58 +10:30
Senthil Kumar Selvaraj
cc9ad334a7 Allow symbols in MEMORY region specification
This patch fixes PR 4643 by allowing symbols in the LENGTH and ORIGIN
fields of MEMORY regions.  Previously, only constants and constant
expressions are allowed.

For the AVR target, this helps define memory constraints more
accurately (per device), without having to create a ton of device
specific linker scripts.

ld/
	PR 4643
	* ldexp.c (fold_name): Fold LENGTH only after
	lang_first_phase_enum.
	* ldgram.y (memory_spec): Don't evaluate ORIGIN and LENGTH
	rightaway.
	* ldlang.h (struct memory_region_struct): Add origin_exp and
	length_exp fields.
	* ldlang.c (lang_do_memory_regions): New.
	(lang_memory_region_lookup): Initialize origin_exp and
	length_exp fields.
	(lang_process): Call lang_do_memory_regions.
ld/testsuite/
	* ld-scripts/memory.t: Define new symbol tred.
	* ld-scripts/memory_sym.t: New.
	* ld-scripts/script.exp: Perform MEMORY with symbols test, and
	conditionally check values of linker symbols.
2015-01-28 15:06:48 +10:30
Alan Modra
b90efa5b79 ChangeLog rotatation and copyright year update 2015-01-02 00:53:45 +10:30
Alan Modra
422f1c65c9 Report an error for script multiply defined symbols
or maybe not just yet, but this is better than a FIXME.

	* ldexp.c (update_definedness): Return false if script symbol is
	redefining a strong symbol in an object.
	(exp_fold_tree_1 <etree_assign>): Set up for reporting a multiple
	definition error, but for now leave disabled.
2014-12-23 23:36:51 +10:30
Alan Modra
12b2843a6b Use a symbol flag bit to mark linker defined symbols
Trying to use the SEC_LINKER_CREATED section flag to determine whether
a symbol is linker defined fails to work on targets like alpha that
define special SEC_COMMON sections.  These might contain symbols that
originated in an object file.

include/
	* bfdlink.h (struct bfd_link_hash_entry): Comment non_ir_ref.  Add
	linker_def.
bfd/
	* elflink.c (_bfd_elf_define_linkage_sym): Set linker_def.
	* linker.c (_bfd_generic_link_add_one_symbol): Clear linker_def
	for CDEF, DEF, DEFW, COM.
ld/
	* ldexp.c (exp_fold_tree_1 <etree_provide>): Test linker_def.
ld/testsuite/
	* ld-powerpc/sdabase.s,
	* ld-powerpc/sdabase.t,
	* ld-powerpc/sdabase.d: New test.
	* ld-powerpc/sdabase2.t,
	* ld-powerpc/sdabase2.d: New test.
	* ld-powerpc/powerpc.exp: Run them.
2014-12-23 23:36:50 +10:30
Alan Modra
4cc2bf08a4 Don't PROVIDE over top of common symbols
This:
  int end[100000];
  int main(void) { end[99999] = 0; return 0; }
should not segfault.

ld/
	* ldexp.c (exp_fold_tree_1 <etree_provide>): Leave bfd_link_hash_common
	symbols alone.
ld/testsuite/
	* ld-elf/endsym.s, *ld-elf/endsym.d: New test.
2014-12-23 23:36:50 +10:30
Alan Modra
cd8e2bcf0d Correct logic for "defined by object"
The old code missed testing bfd_link_hash_undefweak, and wrongly
excluded bfd_link_hash_common symbols.  It is also clearer to invert
the set of enum bfd_link_hash_type values tested.
bfd_link_hash_indirect and bfd_link_hash_warning will never appear
here.

	* ldexp.c (update_definedness): Correct logic setting by_object.
2014-12-23 23:36:50 +10:30
Alan Modra
18d6a79d35 Move support code for linker script DEFINED to ldexp.c
This moves support code for DEFINED to ldexp.c where it is used,
losing the lang_ prefix on identifiers.  Two new functions are needed
to initialize and clean up to hash table, but other than that there
are no functional changes here.

	* ldexp.c (struct definedness_hash_entry, definedness_table)
	(definedness_newfunc, symbol_defined, update_definedness): Move
	and rename from..
	* ldlang.h (struct lang_definedness_hash_entry): ..here,..
	* ldlang.c (lang_definedness_table, lang_definedness_newfunc)
	(lang_symbol_defined, lang_update_definedness): ..and here.
	* ldexp.c (ldexp_init, ldexp_finish): New functions, extracted from..
	* ldlang.c (lang_init, lang_finish): ..here.
	* ldexp.h (ldexp_init, ldexp_finish): Declare.
	* ldlang.h (lang_symbol_defined, lang_update_definedness): Delete.
	* ldmain.c (main): Call ldexp_init and ldexp_finish.
2014-12-23 23:36:50 +10:30
Alan Modra
b893397a4b PROVIDE in linker script vs. built-in symbols
* ldexp.c (exp_fold_tree_1 <etree_provide>): Make PROVIDEd
	linker script symbol value override a built-in linker symbol.
2014-06-07 14:55:12 +09:30
Alan Modra
4b95cf5c0c Update copyright years 2014-03-05 22:16:15 +10:30
Alan Modra
2edab91c10 Make assignments to dot keep an empty output section.
An assignment to dot in an output section that allocates space of
course keeps the output section.  Here, I'm changing the behaviour for
assignments that don't allocate space.  The idea is not so much to
allow people to force output of an empty section with ". = .", but
to fix cases where an otherwise empty section has padding added by an
alignment expression that changes with relaxation or .eh_frame
editing.  Such a section might have zero size before relaxation and so
be stripped incorrectly.

ld/
	* ld.texinfo (Output Section Discarding): Mention assigning to dot
	as a way of keeping otherwise empty sections.
	* ldexp.c (is_dot, is_value, is_sym_value, is_dot_ne_0,
	is_dot_plus_0, is_align_conditional): New predicates.
	(exp_fold_tree_1): Set SEC_KEEP when assigning to dot inside an
	output section, except for some special cases.
	* scripttempl/elfmicroblaze.sc: Use canonical form to align at
	end of .heap and .stack.
ld/testsuite/
	* ld-shared/elf-offset.ld: Align end of .bss with canonical form
	of ALIGN that allows an empty .bss to be removed.
	* ld-arm/arm-dyn.ld: Likewise.
	* ld-arm/arm-lib.ld: Likewise.
	* ld-elfvsb/elf-offset.ld: Likewise.
	* ld-mips-elf/mips-dyn.ld: Likewise.
	* ld-mips-elf/mips-lib.ld: Likewise.
	* ld-arm/arm-no-rel-plt.ld: Remove duplicate ALIGN.
	* ld-powerpc/vle-multiseg-1.ld: Remove ALIGN at start of section.
	ALIGN address of section instead.
	* ld-powerpc/vle-multiseg-2.ld: Likewise.
	* ld-powerpc/vle-multiseg-3.ld: Likewise.
	* ld-powerpc/vle-multiseg-4.ld: Likewise.
	* ld-powerpc/vle-multiseg-6.ld: Likewise.
	* ld-scripts/empty-aligned.d: Check section headers not program
	headers.  Remove xfail and notarget.
	* ld-scripts/empty-aligned.t: Use canonical ALIGN for end of .text2.
2014-01-22 11:58:29 +10:30
Alan Modra
fa72205cb9 Allow self-assignment for absolute symbols defined in a linker script
Modifies ld machinery tracking linker script assignments to notice all
assignments, not just those symbols mentioned in DEFINED().

ld/
	PR ld/14962
	* ldlang.h (struct lang_definedness_hash_entry): Add by_object and
	by_script.  Make iteration a single bit field.
	(lang_track_definedness, lang_symbol_definition_iteration): Delete.
	(lang_symbol_defined): Declare.
	* ldlang.c (lang_statement_iteration): Expand comment a little.
	(lang_init <lang_definedness_table>): Make it bigger.
	(lang_track_definedness, lang_symbol_definition): Delete.
	(lang_definedness_newfunc): Update.
	(lang_symbol_defined): New function.
	(lang_update_definedness): Create entries here.  Do track whether
	script definition of symbol is valid, even when also defined in
	an object file.
	* ldexp.c (fold_name <DEFINED>): Update.
	(fold_name <NAME>): Allow self-assignment for absolute symbols
	defined in a linker script.
ld/testsuite/
	* ld-scripts/pr14962-2.d,
	* ld-scripts/pr14962-2.t: New test.
	* ld-scripts/expr.exp: Run it.
2014-01-20 21:28:42 +10:30