From 60d67dc84bbc7d73672d297d714f8a4a0547618d Mon Sep 17 00:00:00 2001 From: Alan Modra Date: Wed, 22 Nov 2017 17:30:55 +1030 Subject: Rename u.weakdef and make it a circular list This makes the elf_link_hash_entry weakdef field, currently used to point from a weak symbol to a strong alias, a circular list so that all aliases can be found from any of them. A new flag, is_weakalias, distinguishes the weak symbol from a strong alias, and is used in all places where we currently test u.weakdef != NULL. With the original u.weakdef handling it was possible to have two or more weak symbols pointing via u.weakdef to a strong definition. Obviously that situation can't map to a circular list; One or more of the weak symbols must point at another weak alias rather than the strong definition. To handle that, I've added an accessor function to return the strong definition. * elf-bfd.h (struct elf_link_hash_entry): Add is_weakalias. Rename u.weakdef to u.alias and update comment. (weakdef): New static inline function. * elflink.c (bfd_elf_record_link_assignment) Test is_weakalias rather than u.weakdef != NULL, and use weakdef function. (_bfd_elf_adjust_dynamic_symbol): Likewise. (_bfd_elf_fix_symbol_flags): Likewise. Clear is_weakalias on all aliases if def has been overridden in a regular object, not u.weakdef. (elf_link_add_object_symbols): Delete new_weakdef flag. Test is_weakalias and use weakdef. Set is_weakalias and circular u.alias. Update comments. (_bfd_elf_gc_mark_rsec): Test is_weakalias rather than u.weakdef != NULL and use weakdef function. * elf-m10300.c (_bfd_mn10300_elf_adjust_dynamic_symbol): Test is_weakalias rather than u.weakdef != NULL and use weakdef function. Assert that def is strong defined. * elf32-arc.c (elf_arc_adjust_dynamic_symbol): Likewise. * elf32-arm.c (elf32_arm_adjust_dynamic_symbol): Likewise. * elf32-bfin.c (elf32_bfinfdpic_adjust_dynamic_symbol): Likewise. (bfin_adjust_dynamic_symbol): Likewise. * elf32-cr16.c (_bfd_cr16_elf_adjust_dynamic_symbol): Likewise. * elf32-cris.c (elf_cris_adjust_dynamic_symbol): Likewise. * elf32-frv.c (elf32_frvfdpic_adjust_dynamic_symbol): Likewise. * elf32-hppa.c (elf32_hppa_adjust_dynamic_symbol): Likewise. * elf32-i370.c (i370_elf_adjust_dynamic_symbol): Likewise. * elf32-lm32.c (lm32_elf_adjust_dynamic_symbol): Likewise. * elf32-m32r.c (m32r_elf_adjust_dynamic_symbol): Likewise. * elf32-m68k.c (elf_m68k_adjust_dynamic_symbol): Likewise. * elf32-metag.c (elf_metag_adjust_dynamic_symbol): Likewise. * elf32-microblaze.c (microblaze_elf_adjust_dynamic_symbol): Likewise. * elf32-nds32.c (nds32_elf_adjust_dynamic_symbol): Likewise. * elf32-nios2.c (nios2_elf32_adjust_dynamic_symbol): Likewise. * elf32-or1k.c (or1k_elf_adjust_dynamic_symbol): Likewise. * elf32-ppc.c (ppc_elf_adjust_dynamic_symbol): Likewise. * elf32-s390.c (elf_s390_adjust_dynamic_symbol): Likewise. * elf32-score.c (s3_bfd_score_elf_adjust_dynamic_symbol): Likewise. * elf32-score7.c (s7_bfd_score_elf_adjust_dynamic_symbol): Likewise. * elf32-sh.c (sh_elf_adjust_dynamic_symbol): Likewise. * elf32-tic6x.c (elf32_tic6x_adjust_dynamic_symbol): Likewise. * elf32-tilepro.c (tilepro_elf_gc_mark_hook): Likewise. (tilepro_elf_adjust_dynamic_symbol): Likewise. * elf32-vax.c (elf_vax_adjust_dynamic_symbol): Likewise. * elf32-xtensa.c (elf_xtensa_adjust_dynamic_symbol): Likewise. * elf64-alpha.c (elf64_alpha_adjust_dynamic_symbol): Likewise. * elf64-hppa.c (elf64_hppa_adjust_dynamic_symbol): Likewise. * elf64-ia64-vms.c (elf64_ia64_adjust_dynamic_symbol): Likewise. * elf64-ppc.c (ppc64_elf_gc_mark_hook): Likewise. (ppc64_elf_adjust_dynamic_symbol): Likewise. * elf64-s390.c (elf_s390_adjust_dynamic_symbol): Likewise. * elf64-sh64.c (sh64_elf64_adjust_dynamic_symbol): Likewise. * elfnn-aarch64.c (elfNN_aarch64_adjust_dynamic_symbol): Likewise. * elfnn-ia64.c (elfNN_ia64_adjust_dynamic_symbol): Likewise. * elfnn-riscv.c (riscv_elf_adjust_dynamic_symbol): Likewise. * elfxx-mips.c (_bfd_mips_elf_adjust_dynamic_symbol): Likewise. * elfxx-sparc.c (_bfd_sparc_elf_gc_mark_hook): Likewise. (_bfd_sparc_elf_adjust_dynamic_symbol): Likewise. * elfxx-tilegx.c (tilegx_elf_gc_mark_hook): Likewise. (tilegx_elf_adjust_dynamic_symbol): Likewise. * elfxx-x86.c (_bfd_x86_elf_adjust_dynamic_symbol): Likewise. --- bfd/elf-bfd.h | 22 +++++++++++++++++----- 1 file changed, 17 insertions(+), 5 deletions(-) (limited to 'bfd/elf-bfd.h') diff --git a/bfd/elf-bfd.h b/bfd/elf-bfd.h index 954105e..aebfbd9 100644 --- a/bfd/elf-bfd.h +++ b/bfd/elf-bfd.h @@ -216,20 +216,22 @@ struct elf_link_hash_entry /* Symbol is __start_SECNAME or __stop_SECNAME to mark section SECNAME. */ unsigned int start_stop : 1; + /* Symbol is or was a weak defined symbol from a dynamic object with + a strong defined symbol alias. U.ALIAS points to a list of aliases, + the definition having is_weakalias clear. */ + unsigned int is_weakalias : 1; /* String table index in .dynstr if this is a dynamic symbol. */ unsigned long dynstr_index; union { - /* If this is a weak defined symbol from a dynamic object, this - field points to a defined symbol with the same value, if there is - one. Otherwise it is NULL. */ - struct elf_link_hash_entry *weakdef; + /* Points to a circular list of non-function symbol aliases. */ + struct elf_link_hash_entry *alias; /* Hash value of the name computed using the ELF hash function. Used part way through size_dynamic_sections, after we've finished - with weakdefs. */ + with aliases. */ unsigned long elf_hash_value; } u; @@ -257,6 +259,16 @@ struct elf_link_hash_entry } u2; }; +/* Return the strong definition for a weak symbol with aliases. */ + +static inline struct elf_link_hash_entry * +weakdef (struct elf_link_hash_entry *h) +{ + while (h->is_weakalias) + h = h->u.alias; + return h; +} + /* Will references to this symbol always reference the symbol in this object? */ #define SYMBOL_REFERENCES_LOCAL(INFO, H) \ -- cgit v1.1