From eac61af65bcd24a48633da375527eb3f36ab47ed Mon Sep 17 00:00:00 2001 From: Tom Tromey Date: Thu, 28 Jun 2018 08:02:42 -0600 Subject: [PATCH] Allow BFD to recognize macOS universal libraries Bug #13157 is about a gdb regression, where previously it could handle universal libraries, but now cannot. gdb isn't working for me on macOS for other reasons, so I wrote this small test program to show the problem: #include #include #include #include void die (const char *what) { fprintf (stderr, "die: %s\n", what); exit (1); } int main (int argc, char **argv) { bfd *file = bfd_openr (argv[1], NULL); if (file == NULL) die ("couldn't open"); if (!bfd_check_format (file, bfd_archive)) die ("not an archive"); printf ("yay\n"); bfd_close (file); return 0; } Then I built a simple universal binary. With git master BFD, I get: $ ./doit ./universal-exe die: not an archive Jeff Muizelaar tracked this down to the BFD change for PR binutils/21787. This patch changed bfd_generic_archive_p to sometimes reset the BFD's "format" field. However, simply changing bfd_generic_archive_p regressed the test case in that bug. Debugging PR binutils/21787 again, what I saw is that the mach-o universal binary support acts like a bfd_archive but does not provide a _close_and_cleanup function. However, if a BFD appears as an archive member, it must always remove its own entry from its parent's map. Otherwise, when the parent is destroyed, the already-destroyed child BFD will be referenced. mach-o does not use the usual archive member support, so simply using _bfd_archive_close_and_cleanup (as other targets do) will not work. This patch fixes the problem by introducing a new _bfd_unlink_from_archive_parent function, then arranging for it to be called in the mach-o case. Ok? bfd/ChangeLog 2018-07-02 Jeff Muizelaar Tom Tromey PR 13157 PR 21787 * mach-o.c (bfd_mach_o_fat_close_and_cleanup): New function. (bfd_mach_o_close_and_cleanup): Redefine. * archive.c (_bfd_unlink_from_archive_parent): New function, extracted from.. (_bfd_archive_close_and_cleanup): ..here. (bfd_generic_archive_p): Do not clear archive's format. * libbfd-in.h (_bfd_unlink_from_archive_parent): Declare. * libbfd.h: Regenerate. --- bfd/ChangeLog | 14 ++++++++++++++ bfd/archive.c | 44 +++++++++++++++++++++++++------------------- bfd/libbfd-in.h | 1 + bfd/libbfd.h | 1 + bfd/mach-o.c | 9 ++++++++- 5 files changed, 49 insertions(+), 20 deletions(-) diff --git a/bfd/ChangeLog b/bfd/ChangeLog index 96d7a4d..a7d8ce7 100644 --- a/bfd/ChangeLog +++ b/bfd/ChangeLog @@ -1,3 +1,17 @@ +2018-07-02 Jeff Muizelaar + Tom Tromey + + PR 13157 + PR 21787 + * mach-o.c (bfd_mach_o_fat_close_and_cleanup): New function. + (bfd_mach_o_close_and_cleanup): Redefine. + * archive.c (_bfd_unlink_from_archive_parent): New function, + extracted from.. + (_bfd_archive_close_and_cleanup): ..here. + (bfd_generic_archive_p): Do not clear archive's format. + * libbfd-in.h (_bfd_unlink_from_archive_parent): Declare. + * libbfd.h: Regenerate. + 2018-07-02 Thomas Preud'homme * archures.c (bfd_mach_arm_5TEJ, bfd_mach_arm_6, bfd_mach_arm_6KZ, diff --git a/bfd/archive.c b/bfd/archive.c index d56bb06..a51c135 100644 --- a/bfd/archive.c +++ b/bfd/archive.c @@ -850,8 +850,6 @@ bfd_generic_archive_p (bfd *abfd) && ! bfd_is_thin_archive (abfd)) { bfd_set_error (bfd_error_wrong_format); - if (abfd->format == bfd_archive) - abfd->format = bfd_unknown; return NULL; } @@ -2765,6 +2763,30 @@ archive_close_worker (void **slot, void *inf ATTRIBUTE_UNUSED) return 1; } +void +_bfd_unlink_from_archive_parent (bfd *abfd) +{ + if (arch_eltdata (abfd) != NULL) + { + struct areltdata *ared = arch_eltdata (abfd); + htab_t htab = (htab_t) ared->parent_cache; + + if (htab) + { + struct ar_cache ent; + void **slot; + + ent.ptr = ared->key; + slot = htab_find_slot (htab, &ent, NO_INSERT); + if (slot != NULL) + { + BFD_ASSERT (((struct ar_cache *) *slot)->arbfd == abfd); + htab_clear_slot (htab, slot); + } + } + } +} + bfd_boolean _bfd_archive_close_and_cleanup (bfd *abfd) { @@ -2789,25 +2811,9 @@ _bfd_archive_close_and_cleanup (bfd *abfd) bfd_ardata (abfd)->cache = NULL; } } - if (arch_eltdata (abfd) != NULL) - { - struct areltdata *ared = arch_eltdata (abfd); - htab_t htab = (htab_t) ared->parent_cache; - if (htab) - { - struct ar_cache ent; - void **slot; + _bfd_unlink_from_archive_parent (abfd); - ent.ptr = ared->key; - slot = htab_find_slot (htab, &ent, NO_INSERT); - if (slot != NULL) - { - BFD_ASSERT (((struct ar_cache *) *slot)->arbfd == abfd); - htab_clear_slot (htab, slot); - } - } - } if (abfd->is_linker_output) (*abfd->link.hash->hash_table_free) (abfd); diff --git a/bfd/libbfd-in.h b/bfd/libbfd-in.h index 3c55adf..e53b255 100644 --- a/bfd/libbfd-in.h +++ b/bfd/libbfd-in.h @@ -277,6 +277,7 @@ extern int bfd_generic_stat_arch_elt #define _bfd_generic_close_and_cleanup _bfd_archive_close_and_cleanup extern bfd_boolean _bfd_archive_close_and_cleanup (bfd *) ATTRIBUTE_HIDDEN; +extern void _bfd_unlink_from_archive_parent (bfd *) ATTRIBUTE_HIDDEN; #define _bfd_generic_bfd_free_cached_info _bfd_bool_bfd_true extern bfd_boolean _bfd_generic_new_section_hook (bfd *, asection *) ATTRIBUTE_HIDDEN; diff --git a/bfd/libbfd.h b/bfd/libbfd.h index 85f61b2..a884aab 100644 --- a/bfd/libbfd.h +++ b/bfd/libbfd.h @@ -282,6 +282,7 @@ extern int bfd_generic_stat_arch_elt #define _bfd_generic_close_and_cleanup _bfd_archive_close_and_cleanup extern bfd_boolean _bfd_archive_close_and_cleanup (bfd *) ATTRIBUTE_HIDDEN; +extern void _bfd_unlink_from_archive_parent (bfd *) ATTRIBUTE_HIDDEN; #define _bfd_generic_bfd_free_cached_info _bfd_bool_bfd_true extern bfd_boolean _bfd_generic_new_section_hook (bfd *, asection *) ATTRIBUTE_HIDDEN; diff --git a/bfd/mach-o.c b/bfd/mach-o.c index d58e62d..ce72a3d 100644 --- a/bfd/mach-o.c +++ b/bfd/mach-o.c @@ -5532,6 +5532,13 @@ bfd_mach_o_fat_extract (bfd *abfd, return NULL; } +static bfd_boolean +bfd_mach_o_fat_close_and_cleanup (bfd *abfd) +{ + _bfd_unlink_from_archive_parent (abfd); + return TRUE; +} + int bfd_mach_o_lookup_command (bfd *abfd, bfd_mach_o_load_command_type type, @@ -6026,7 +6033,7 @@ bfd_mach_o_free_cached_info (bfd *abfd) /* Not yet handled: creating an archive. */ #define bfd_mach_o_mkarchive _bfd_noarchive_mkarchive -#define bfd_mach_o_close_and_cleanup _bfd_bool_bfd_true +#define bfd_mach_o_close_and_cleanup bfd_mach_o_fat_close_and_cleanup /* Not used. */ #define bfd_mach_o_generic_stat_arch_elt bfd_mach_o_fat_stat_arch_elt -- 2.7.4