From 160826fefd78b57a02adb87f9977b7fb31095084 Mon Sep 17 00:00:00 2001 From: Alan Modra Date: Tue, 24 Oct 2017 23:15:01 +1030 Subject: [PATCH] PR82687, g++.dg/asan/default-options-1.C fails with PR82575 fix The problem with making discarded symbols hidden is that the non-default visibility is sticky. When symbols other than the __gnu_lto ones are discarded that turns out to be a bad idea. PR lto/82687 PR lto/82575 * simple-object-elf.c (simple_object_elf_copy_lto_debug_sections): Only make __gnu_lto symbols hidden. Delete outdated comment. Silence ISO C warning. From-SVN: r254042 --- libiberty/ChangeLog | 7 +++++++ libiberty/simple-object-elf.c | 29 +++++++++++++++++++---------- 2 files changed, 26 insertions(+), 10 deletions(-) diff --git a/libiberty/ChangeLog b/libiberty/ChangeLog index 46dc0fa7e04..eb3cbc1819d 100644 --- a/libiberty/ChangeLog +++ b/libiberty/ChangeLog @@ -1,3 +1,10 @@ +2017-10-24 Alan Modra + + PR lto/82687 + PR lto/82575 + * simple-object-elf.c (simple_object_elf_copy_lto_debug_sections): + Only make __gnu_lto symbols hidden. + 2017-10-20 Alan Modra PR lto/82575 diff --git a/libiberty/simple-object-elf.c b/libiberty/simple-object-elf.c index 1afd3ebc951..14f71053150 100644 --- a/libiberty/simple-object-elf.c +++ b/libiberty/simple-object-elf.c @@ -1088,6 +1088,7 @@ simple_object_elf_copy_lto_debug_sections (simple_object_read *sobj, off_t shstroff; unsigned char *names; unsigned int i; + int changed; int *pfnret; const char **pfnname; @@ -1161,7 +1162,6 @@ simple_object_elf_copy_lto_debug_sections (simple_object_read *sobj, /* Mark sections as preserved that are required by to be preserved sections. */ - int changed; do { changed = 0; @@ -1349,9 +1349,6 @@ simple_object_elf_copy_lto_debug_sections (simple_object_read *sobj, and __gnu_lto_slim which otherwise cause endless LTO plugin invocation. */ if (st_shndx == SHN_COMMON) - /* Setting st_name to "" seems to work to purge - COMMON symbols (in addition to setting their - size to zero). */ discard = 1; /* We also need to remove symbols refering to sections we'll eventually remove as with fat LTO objects @@ -1368,17 +1365,29 @@ simple_object_elf_copy_lto_debug_sections (simple_object_read *sobj, /* Make discarded symbols undefined and unnamed in case it is local. */ int bind = ELF_ST_BIND (*st_info); + int other = STV_DEFAULT; + size_t st_name; + if (bind == STB_LOCAL) - { - ELF_SET_FIELD (type_functions, ei_class, Sym, - ent, st_name, Elf_Word, 0); - *st_other = STV_DEFAULT; - } + ELF_SET_FIELD (type_functions, ei_class, Sym, + ent, st_name, Elf_Word, 0); else { bind = STB_WEAK; - *st_other = STV_HIDDEN; + st_name = ELF_FETCH_FIELD (type_functions, ei_class, + Sym, ent, st_name, + Elf_Word); + if (st_name < strsz) + { + char *p = strings + st_name; + if (p[0] == '_' + && p[1] == '_' + && strncmp (p + (p[2] == '_'), + "__gnu_lto_", 10) == 0) + other = STV_HIDDEN; + } } + *st_other = other; *st_info = ELF_ST_INFO (bind, STT_NOTYPE); ELF_SET_FIELD (type_functions, ei_class, Sym, ent, st_value, Elf_Addr, 0); -- 2.30.2