In some cases, BFD leaves excessive relocation for .ARM.exidx. Though I cannot provide the actual binary, I'll detail what I figured out while investigating the issue. The bug reproduces if: * merged exidx have duplicate entries, which should be deleted AND * the target is relocatable executable (i.e. bfd_link_relocatable is FALSE, but emitrelocations is TRUE) Merged exidx can have duplicate entries, and the later ones will be marked to be deleted if bfd_link_relocatable is FALSE (see elf32_arm_fix_exidx_coverage in bfd/elf32-arm.c). However, it just means it is incremental link, and it's FALSE even for relocatable executable. In such cases, relocations should be updated, but they won't. As the result, the excessive relocations remains the final output and the later relocations in the section will slip from the expected offset.
Workaround: Comment out line [1231,1237] in bfd/elf32-arm.c to prevent from deleting entries. diff --git a/bfd/elf32-arm.c b/bfd/elf32-arm.c index 3d4a458..e0056ee 100644 --- a/bfd/elf32-arm.c +++ b/bfd/elf32-arm.c @@ -12028,6 +12028,7 @@ elf32_arm_fix_exidx_coverage (asection **text_section_order, else unwind_type = 2; +/* if (elide && !bfd_link_relocatable (info)) { add_unwind_table_edit (&unwind_edit_head, &unwind_edit_tail, @@ -12035,6 +12036,7 @@ elf32_arm_fix_exidx_coverage (asection **text_section_order, deleted_exidx_bytes += 8; } +*/ last_unwind_type = unwind_type; }
A patch to add a test case sent to the mailing list. https://sourceware.org/ml/binutils/2016-09/msg00048.html
A fix sent to the mailing list. https://sourceware.org/ml/binutils/2016-09/msg00062.html
The master branch has been updated by Nick Clifton <nickc@sourceware.org>: https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=5025eb7c0d87b01507116353b5d63b163d7add3d commit 5025eb7c0d87b01507116353b5d63b163d7add3d Author: Akihiko Odaki <akihiko.odaki.4i@stu.hosei.ac.jp> Date: Fri Sep 23 16:32:04 2016 +0100 Delete relocations associatesd with deleted exidx entries. PR ld/20595 ld * testsuite/ld-arm/unwind-4.d: Add -q option to linker command line and -r option to objdump command line. Match emitted relocs to make sure that superflous relocs are not generated. bfd * elf-bfd.h (struct elf_backend_data): Add elf_backend_count_output_relocs callback to count relocations in the final output. * elf-arm.c (elf32_arm_add_relocation): Deleted. (elf32_arm_write_section): Move additional relocation to emit_relocs. (elf32_arm_count_output_relocs): New function. (emit_relocs): New function. (elf32_arm_emit_relocs): New function. (elf32_arm_vxworks_emit_relocs): New function. (elf_backend_emit_relocs): Updated to use the new functions. (elf_backend_count_output_relocs): New define. * bfd/elflink.c (bfd_elf_final_link): Do not add additional_reloc_count to the relocation count. (_bfd_elf_link_size_reloc_section): Use callback to count the relocations which will be in output. (_bfd_elf_default_count_output_relocs): New function. * bfd/elfxx-target.h (elf_backend_count_output_relocs): New define.
Patch applied (fix & testsuite update).
The master branch has been updated by Nick Clifton <nickc@sourceware.org>: https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=a24bb4f0cce83eea8b2ad1542316651143af6f90 commit a24bb4f0cce83eea8b2ad1542316651143af6f90 Author: Nick Clifton <nickc@redhat.com> Date: Tue Oct 11 13:50:10 2016 +0100 Enhance objdump so that it will use .got, .plt and .plt.got section symbols when disassembling, and it will use dynamic relocs to interpret entries in the PLT and GOT. binutils * objdump.c (is_significant_symbol_name): New function. (remove_useless_symbols): Do not remove significanr symbols. (find_symbol_for_address): If an exact match for the specified address has not been found, try scanning the dynamic relocs to see if one of these matches the address. If so, use the symbol associated with the reloc. (objdump_print_addr_with_symbol): Do not print offsets to symbols with no value. (disassemble_section): Only use dynamic relocs if the user requested this. (disassemble_data): Always load dynamic relocs if they are available. ld * ld-aarch64/emit-relocs-515-be.d: Adjust output to match change in objdump. * ld-aarch64/emit-relocs-515.d: Likewise. * ld-aarch64/emit-relocs-516-be.d: Likewise. * ld-aarch64/emit-relocs-516.d: Likewise. * ld-aarch64/farcall-b-plt.d: Likewise. * ld-aarch64/farcall-bl-plt.d: Likewise. * ld-aarch64/gc-plt-relocs.d: Likewise. * ld-aarch64/tls-desc-ie.d: Likewise. * ld-aarch64/tls-tiny-desc.d: Likewise. * ld-aarch64/tls-tiny-gd.d: Likewise. * ld-aarch64/tls-tiny-ie.d: Likewise. * ld-arm/arm-app-abs32.d: Likewise. * ld-arm/arm-app.d: Likewise. * ld-arm/arm-lib-plt32.d: Likewise. * ld-arm/arm-lib.d: Likewise. * ld-arm/armthumb-lib.d: Likewise. * ld-arm/cortex-a8-fix-b-plt.d: Likewise. * ld-arm/cortex-a8-fix-bcc-plt.d: Likewise. * ld-arm/cortex-a8-fix-bl-plt.d: Likewise. * ld-arm/cortex-a8-fix-bl-rel-plt.d: Likewise. * ld-arm/cortex-a8-fix-blx-plt.d: Likewise. * ld-arm/farcall-mixed-app-v5.d: Likewise. * ld-arm/farcall-mixed-app.d: Likewise. * ld-arm/farcall-mixed-app2.d: Likewise. * ld-arm/farcall-mixed-lib-v4t.d: Likewise. * ld-arm/farcall-mixed-lib.d: Likewise. * ld-arm/ifunc-10.dd: Likewise. * ld-arm/ifunc-14.dd: Likewise. * ld-arm/ifunc-15.dd: Likewise. * ld-arm/ifunc-3.dd: Likewise. * ld-arm/ifunc-4.dd: Likewise. * ld-arm/ifunc-9.dd: Likewise. * ld-arm/long-plt-format.d: Likewise. * ld-arm/mixed-app-v5.d: Likewise. * ld-arm/mixed-app.d: Likewise. * ld-arm/mixed-lib.d: Likewise. * ld-arm/tls-lib-loc.d: Likewise. * ld-cris/dso-pltdis1.d: Likewise. * ld-cris/dso-pltdis2.d: Likewise. * ld-cris/dso12-pltdis.d: Likewise. * ld-elf/symbolic-func.r: Likewise. * ld-frv/fdpic-pie-1.d: Likewise. * ld-frv/fdpic-pie-2.d: Likewise. * ld-frv/fdpic-pie-6.d: Likewise. * ld-frv/fdpic-pie-7.d: Likewise. * ld-frv/fdpic-pie-8.d: Likewise. * ld-frv/fdpic-shared-1.d: Likewise. * ld-frv/fdpic-shared-2.d: Likewise. * ld-frv/fdpic-shared-3.d: Likewise. * ld-frv/fdpic-shared-4.d: Likewise. * ld-frv/fdpic-shared-5.d: Likewise. * ld-frv/fdpic-shared-6.d: Likewise. * ld-frv/fdpic-shared-7.d: Likewise. * ld-frv/fdpic-shared-8.d: Likewise. * ld-frv/fdpic-shared-local-2.d: Likewise. * ld-frv/fdpic-shared-local-8.d: Likewise. * ld-frv/fdpic-static-1.d: Likewise. * ld-frv/fdpic-static-2.d: Likewise. * ld-frv/fdpic-static-6.d: Likewise. * ld-frv/fdpic-static-7.d: Likewise. * ld-frv/fdpic-static-8.d: Likewise. * ld-frv/tls-dynamic-2.d: Likewise. * ld-frv/tls-initial-shared-2.d: Likewise. * ld-frv/tls-relax-shared-2.d: Likewise. * ld-frv/tls-shared-2.d: Likewise. * ld-i386/plt-nacl.pd: Likewise. * ld-i386/plt-pic-nacl.pd: Likewise. * ld-i386/plt-pic.pd: Likewise. * ld-i386/plt.pd: Likewise. * ld-i386/pr19636-1d-nacl.d: Likewise. * ld-i386/pr19636-1d.d: Likewise. * ld-i386/pr19636-2c-nacl.d: Likewise. * ld-i386/pr19636-2c.d: Likewise. * ld-ifunc/ifunc-21-x86-64.d: Likewise. * ld-ifunc/ifunc-22-x86-64.d: Likewise. * ld-ifunc/pr17154-i386.d: Likewise. * ld-ifunc/pr17154-x86-64.d: Likewise. * ld-m68k/plt1-68020.d: Likewise. * ld-m68k/plt1-cpu32.d: Likewise. * ld-m68k/plt1-isab.d: Likewise. * ld-m68k/plt1-isac.d: Likewise. * ld-metag/shared.d: Likewise. * ld-metag/stub_pic_app.d: Likewise. * ld-metag/stub_pic_shared.d: Likewise. * ld-metag/stub_shared.d: Likewise. * ld-s390/tlsbin_64.dd: Likewise. * ld-s390/tlspic_64.dd: Likewise. * ld-tic6x/shlib-1.dd: Likewise. * ld-tic6x/shlib-1b.dd: Likewise. * ld-tic6x/shlib-1rb.dd: Likewise. * ld-tic6x/shlib-app-1.dd: Likewise. * ld-tic6x/shlib-app-1b.dd: Likewise. * ld-tic6x/shlib-app-1r.dd: Likewise. * ld-tic6x/shlib-app-1rb.dd: Likewise. * ld-tic6x/shlib-noindex.dd: Likewise. * ld-vax-elf/export-class-data.dd: Likewise. * ld-vax-elf/plt-local-lib.dd: Likewise. * ld-vax-elf/plt-local.dd: Likewise. * ld-x86-64/bnd-ifunc-2.d: Likewise. * ld-x86-64/bnd-plt-1.d: Likewise. * ld-x86-64/gotpcrel1.dd: Likewise. * ld-x86-64/libno-plt-1b.dd: Likewise. * ld-x86-64/load1c-nacl.d: Likewise. * ld-x86-64/load1c.d: Likewise. * ld-x86-64/load1d-nacl.d: Likewise. * ld-x86-64/load1d.d: Likewise. * ld-x86-64/mov1a.d: Likewise. * ld-x86-64/mov1b.d: Likewise. * ld-x86-64/mov1c.d: Likewise. * ld-x86-64/mov1d.d: Likewise. * ld-x86-64/mov2a.d: Likewise. * ld-x86-64/mov2b.d: Likewise. * ld-x86-64/mov2c.d: Likewise. * ld-x86-64/mov2d.d: Likewise. * ld-x86-64/mpx3.dd: Likewise. * ld-x86-64/mpx4.dd: Likewise. * ld-x86-64/no-plt-1a.dd: Likewise. * ld-x86-64/no-plt-1b.dd: Likewise. * ld-x86-64/no-plt-1c.dd: Likewise. * ld-x86-64/no-plt-1e.dd: Likewise. * ld-x86-64/no-plt-1f.dd: Likewise. * ld-x86-64/no-plt-1g.dd: Likewise. * ld-x86-64/plt-main-bnd.dd: Likewise. * ld-x86-64/plt-nacl.pd: Likewise. * ld-x86-64/plt.pd: Likewise. * ld-x86-64/pr18591.d: Likewise. * ld-x86-64/pr19609-1c.d: Likewise. * ld-x86-64/pr19609-1e.d: Likewise. * ld-x86-64/pr19609-1j.d: Likewise. * ld-x86-64/pr19609-1l.d: Likewise. * ld-x86-64/pr19609-1m.d: Likewise. * ld-x86-64/pr19609-5b.d: Likewise. * ld-x86-64/pr19609-5c.d: Likewise. * ld-x86-64/pr19609-5e.d: Likewise. * ld-x86-64/pr19609-6b.d: Likewise. * ld-x86-64/pr19609-7b.d: Likewise. * ld-x86-64/pr19609-7d.d: Likewise. * ld-x86-64/pr19636-2d.d: Likewise. * ld-x86-64/pr20093-1.d: Likewise. * ld-x86-64/pr20093-2.d: Likewise. * ld-x86-64/pr20253-1b.d: Likewise. * ld-x86-64/pr20253-1d.d: Likewise. * ld-x86-64/pr20253-1f.d: Likewise. * ld-x86-64/pr20253-1h.d: Likewise. * ld-x86-64/pr20253-1j.d: Likewise. * ld-x86-64/pr20253-1l.d: Likewise. * ld-x86-64/protected3.d: Likewise. * ld-x86-64/tlsbin.dd: Likewise. * ld-x86-64/tlsbin2.dd: Likewise. * ld-x86-64/tlsbindesc.dd: Likewise. * ld-x86-64/tlsdesc-nacl.pd: Likewise. * ld-x86-64/tlsdesc.dd: Likewise. * ld-x86-64/tlsdesc.pd: Likewise. * ld-x86-64/tlsgd10.dd: Likewise. * ld-x86-64/tlsgd5.dd: Likewise. * ld-x86-64/tlsgd6.dd: Likewise. * ld-x86-64/tlsgd8.dd: Likewise. * ld-x86-64/tlsgdesc.dd: Likewise. * ld-x86-64/tlspic.dd: Likewise. * ld-x86-64/tlspic2.dd: Likewise. 2016-10-11 Nick Clifton <nickc@redhat.com> PR ld/20535 * emultempl/elf32.em (_search_needed): Add support for pseudo environment variables supported by ld.so. Namely $ORIGIN, $LIB and $PLATFORM. * configure.ac: Add getauxval to list AC_CHECK_FUNCS list. * config.in: Regenerate. * configure: Regenerate. 2016-10-11 Alan Modra <amodra@gmail.com> * ldlang.c (lang_do_assignments_1): Descend into output section statements that do not yet have bfd sections. Set symbol section temporarily for symbols defined in such statements to the undefined section. Don't error on data or reloc statements until final phase. * ldexp.c (exp_fold_tree_1 <etree_assign>): Handle bfd_und_section in expld.section. * testsuite/ld-mmix/bpo-10.d: Adjust. * testsuite/ld-mmix/bpo-11.d: Adjust. 2016-10-10 Andreas Krebbel <krebbel@linux.vnet.ibm.com> * emulparams/elf64_s390.sh: Move binary start to 16M. * testsuite/ld-s390/tlsbin_64.dd: Adjust testcases accordingly. * testsuite/ld-s390/tlsbin_64.rd: Likewise. 2016-10-07 Alan Modra <amodra@gmail.com> * ldexp.c (MAX): Define. (exp_unop, exp_binop, exp_trinop): Alloc at least enough for etree_type.value. 2016-10-07 Alan Modra <amodra@gmail.com> * testsuite/lib/ld-lib.exp (is_generic_elf): New, extracted from.. * testsuite/ld-elf/elf.exp: ..here. 2016-10-06 Ludovic Court?s <ludo@gnu.org> * emulparams/elf32bmipn32-defs.sh: Shift quote of "x$EMULATION_NAME" to the left to work around <http://ftp.gnu.org/gnu/bash/bash-4.2-patches/bash42-007>. 2016-10-06 Alan Modra <amodra@gmail.com> * lexsup.c: Spell fall through comments consistently and add missing fall through comments. 2016-10-06 Alan Modra <amodra@gmail.com> * plugin.c (asymbol_from_plugin_symbol): Avoid compiler warning by adding return. 2016-10-04 Alan Modra <amodra@gmail.com> * ld.texinfo (Expression Section): Update result of arithmetic expressions. * ldexp.c (arith_result_section): New function. (fold_binary): Use it. 2016-10-04 Alan Modra <amodra@gmail.com> * ldexp.c (exp_value_fold): New function. (exp_unop, exp_binop, exp_trinop): Use it. 2016-09-30 Alan Modra <amodra@gmail.com> * scripttempl/v850.sc: Don't reference __ctbp, __ep, __gp when not relocating. * scripttempl/v850_rh850.sc: Likewise. 2016-09-30 Alan Modra <amodra@gmail.com> PR ld/20528 * testsuite/ld-elf/pr20528a.d: xfail generic elf targets. Allow multiple .text sections for hppa-linux. * testsuite/ld-elf/pr20528b.d: Likewise. 2016-09-30 Alan Modra <amodra@gmail.com> * ldmain.c (default_bfd_error_handler): New function pointer. (ld_bfd_error_handler): New function. (main): Arrange to call it on bfd errors/warnings. (ld_bfd_assert_handler): Enable tail call. 2016-09-30 Alan Modra <amodra@gmail.com> * ldlang.c (ignore_bfd_errors): Update params. 2016-09-29 H.J. Lu <hongjiu.lu@intel.com> PR ld/20528 * emultempl/elf32.em (gld${EMULATION_NAME}_place_orphan): Don't merge 2 sections with different SHF_EXCLUDE. * testsuite/ld-elf/pr20528a.d: New file. * testsuite/ld-elf/pr20528a.s: Likewise. * testsuite/ld-elf/pr20528b.d: Likewise. * testsuite/ld-elf/pr20528b.s: Likewise. 2016-09-28 Christophe Lyon <christophe.lyon@linaro.org> PR ld/20608 * testsuite/ld-arm/arm-elf.exp: Handle new testcase. * testsuite/ld-arm/farcall-mixed-app2.d: New file. * testsuite/ld-arm/farcall-mixed-app2.r: Likewise. * testsuite/ld-arm/farcall-mixed-app2.s: Likewise. * testsuite/ld-arm/farcall-mixed-app2.sym: Likewise. 2016-09-26 Vlad Zakharov <vzakhar@synopsys.com> * Makefile.in: Regenerate. * configure: Likewise. 2016-09-26 Alan Modra <amodra@gmail.com> * testsuite/ld-powerpc/attr-gnu-4-4.s: Delete. * testsuite/ld-powerpc/attr-gnu-4-14.d: Delete. * testsuite/ld-powerpc/attr-gnu-4-24.d: Delete. * testsuite/ld-powerpc/attr-gnu-4-34.d: Delete. * testsuite/ld-powerpc/attr-gnu-4-41.d: Delete. * testsuite/ld-powerpc/attr-gnu-4-32.d: Adjust expected warning. * testsuite/ld-powerpc/attr-gnu-8-23.d: Likewise. * testsuite/ld-powerpc/attr-gnu-4-01.d: Adjust expected output. * testsuite/ld-powerpc/attr-gnu-4-02.d: Likewise. * testsuite/ld-powerpc/attr-gnu-4-03.d: Likewise. * testsuite/ld-powerpc/attr-gnu-4-10.d: Likewise. * testsuite/ld-powerpc/attr-gnu-4-11.d: Likewise. * testsuite/ld-powerpc/attr-gnu-4-20.d: Likewise. * testsuite/ld-powerpc/attr-gnu-4-22.d: Likewise. * testsuite/ld-powerpc/attr-gnu-4-33.d: Likewise. * testsuite/ld-powerpc/attr-gnu-8-11.d: Likewise. * testsuite/ld-powerpc/powerpc.exp: Don't run deleted tests. 2016-09-23 Akihiko Odaki <akihiko.odaki.4i@stu.hosei.ac.jp> PR ld/20595 * testsuite/ld-arm/unwind-4.d: Add -q option to linker command line and -r option to objdump command line. Match emitted relocs to make sure that superflous relocs are not generated. 2016-09-23 Andreas Krebbel <krebbel@linux.vnet.ibm.com> * emulparams/elf64_s390.sh: Change TEXT_START_ADDR to 256MB. * testsuite/ld-s390/tlsbin_64.dd: Adjust testcase accordingly. * testsuite/ld-s390/tlsbin_64.rd: Likewise. 2016-09-22 Nick Clifton <nickc@redhat.com> * emultempl/elf32.em (_try_needed): In verbose mode, report failed attempts to find a needed library. 2016-09-21 Richard Sandiford <richard.sandiford@arm.com> * testsuite/ld-aarch64/emit-relocs-28.d: Expect spaces after "," in addresses. * testsuite/ld-aarch64/emit-relocs-301-be.d: Likewise. * testsuite/ld-aarch64/emit-relocs-301.d: Likewise. * testsuite/ld-aarch64/emit-relocs-302-be.d: Likewise. * testsuite/ld-aarch64/emit-relocs-302.d: Likewise. * testsuite/ld-aarch64/emit-relocs-310-be.d: Likewise. * testsuite/ld-aarch64/emit-relocs-310.d: Likewise. * testsuite/ld-aarch64/emit-relocs-313.d: Likewise. * testsuite/ld-aarch64/emit-relocs-515-be.d: Likewise. * testsuite/ld-aarch64/emit-relocs-515.d: Likewise. * testsuite/ld-aarch64/emit-relocs-516-be.d: Likewise. * testsuite/ld-aarch64/emit-relocs-516.d: Likewise. * testsuite/ld-aarch64/emit-relocs-531.d: Likewise. * testsuite/ld-aarch64/emit-relocs-532.d: Likewise. * testsuite/ld-aarch64/emit-relocs-533.d: Likewise. * testsuite/ld-aarch64/emit-relocs-534.d: Likewise. * testsuite/ld-aarch64/emit-relocs-535.d: Likewise. * testsuite/ld-aarch64/emit-relocs-536.d: Likewise. * testsuite/ld-aarch64/emit-relocs-537.d: Likewise. * testsuite/ld-aarch64/emit-relocs-538.d: Likewise. * testsuite/ld-aarch64/erratum835769.d: Likewise. * testsuite/ld-aarch64/erratum843419.d: Likewise. * testsuite/ld-aarch64/farcall-b-plt.d: Likewise. * testsuite/ld-aarch64/farcall-bl-plt.d: Likewise. * testsuite/ld-aarch64/gc-plt-relocs.d: Likewise. * testsuite/ld-aarch64/ifunc-21.d: Likewise. * testsuite/ld-aarch64/ifunc-7c.d: Likewise. * testsuite/ld-aarch64/tls-desc-ie.d: Likewise. * testsuite/ld-aarch64/tls-large-desc-be.d: Likewise. * testsuite/ld-aarch64/tls-large-desc.d: Likewise. * testsuite/ld-aarch64/tls-large-ie-be.d: Likewise. * testsuite/ld-aarch64/tls-large-ie.d: Likewise. * testsuite/ld-aarch64/tls-relax-all.d: Likewise. * testsuite/ld-aarch64/tls-relax-gd-ie.d: Likewise. * testsuite/ld-aarch64/tls-relax-gdesc-ie-2.d: Likewise. * testsuite/ld-aarch64/tls-relax-gdesc-ie.d: Likewise. * testsuite/ld-aarch64/tls-relax-large-desc-ie-be.d: Likewise. * testsuite/ld-aarch64/tls-relax-large-desc-ie.d: Likewise. * testsuite/ld-aarch64/tls-tiny-desc.d: Likewise. * testsuite/ld-aarch64/tls-tiny-gd.d: Likewise. gas * gas/arm/tls.d: Adjust output to match change in objdump.