From 10bbbc1d790836122c417fe4fef7233604bb3982 Mon Sep 17 00:00:00 2001 From: Nick Clifton Date: Tue, 13 Jun 2017 14:03:16 +0100 Subject: [PATCH] Prevent a call to abort when a relocatable link encounters a relocation against a symbol in a section removed by garbage collection. PR ld/21524 * elflink.c (elf_link_adjust_relocs): Generate an error when encountering a reloc against a symbol removed by garbage collection. --- bfd/ChangeLog | 7 +++++++ bfd/elflink.c | 23 +++++++++++++++++++---- 2 files changed, 26 insertions(+), 4 deletions(-) diff --git a/bfd/ChangeLog b/bfd/ChangeLog index daea173..acddb3a 100644 --- a/bfd/ChangeLog +++ b/bfd/ChangeLog @@ -1,3 +1,10 @@ +2017-06-13 Nick Clifton + + PR ld/21524 + * elflink.c (elf_link_adjust_relocs): Generate an error when + encountering a reloc against a symbol removed by garbage + collection. + 2017-06-12 H.J. Lu * elf-bfd.h (elf_backend_data): Add struct bfd_link_info * diff --git a/bfd/elflink.c b/bfd/elflink.c index 1b447bb..f0ca33f 100644 --- a/bfd/elflink.c +++ b/bfd/elflink.c @@ -8547,7 +8547,8 @@ static bfd_boolean elf_link_adjust_relocs (bfd *abfd, asection *sec, struct bfd_elf_section_reloc_data *reldata, - bfd_boolean sort) + bfd_boolean sort, + struct bfd_link_info *info) { unsigned int i; const struct elf_backend_data *bed = get_elf_backend_data (abfd); @@ -8595,6 +8596,20 @@ elf_link_adjust_relocs (bfd *abfd, if (*rel_hash == NULL) continue; + if ((*rel_hash)->indx == -2 + && info->gc_sections + && ! info->gc_keep_exported) + { + /* PR 21524: Let the user know if a symbol was removed by garbage collection. */ + _bfd_error_handler (_("%B:%A: error: relocation references symbol %s which was removed by garbage collection."), + abfd, sec, + (*rel_hash)->root.root.string); + _bfd_error_handler (_("%B:%A: error: try relinking with --gc-keep-exported enabled."), + abfd, sec, + (*rel_hash)->root.root.string); + bfd_set_error (bfd_error_invalid_operation); + return FALSE; + } BFD_ASSERT ((*rel_hash)->indx >= 0); (*swap_in) (abfd, erela, irela); @@ -10701,7 +10716,6 @@ elf_link_input_bfd (struct elf_final_link_info *flinfo, bfd *input_bfd) used by a reloc. */ BFD_ASSERT (rh->indx < 0); rh->indx = -2; - *rel_hash = rh; continue; @@ -12168,15 +12182,16 @@ bfd_elf_final_link (bfd *abfd, struct bfd_link_info *info) { struct bfd_elf_section_data *esdo = elf_section_data (o); bfd_boolean sort; + if ((o->flags & SEC_RELOC) == 0) continue; sort = bed->sort_relocs_p == NULL || (*bed->sort_relocs_p) (o); if (esdo->rel.hdr != NULL - && !elf_link_adjust_relocs (abfd, o, &esdo->rel, sort)) + && !elf_link_adjust_relocs (abfd, o, &esdo->rel, sort, info)) return FALSE; if (esdo->rela.hdr != NULL - && !elf_link_adjust_relocs (abfd, o, &esdo->rela, sort)) + && !elf_link_adjust_relocs (abfd, o, &esdo->rela, sort, info)) return FALSE; /* Set the reloc_count field to 0 to prevent write_relocs from -- 2.7.4