diff options
| -rw-r--r-- | bfd/ChangeLog | 7 | ||||
| -rw-r--r-- | bfd/elflink.c | 3 | ||||
| -rw-r--r-- | gold/ChangeLog | 12 | ||||
| -rw-r--r-- | gold/layout.cc | 5 | ||||
| -rw-r--r-- | gold/options.cc | 16 | ||||
| -rw-r--r-- | gold/options.h | 15 | ||||
| -rw-r--r-- | include/ChangeLog | 4 | ||||
| -rw-r--r-- | include/bfdlink.h | 7 | ||||
| -rw-r--r-- | ld/ChangeLog | 8 | ||||
| -rw-r--r-- | ld/NEWS | 3 | ||||
| -rw-r--r-- | ld/emultempl/elf.em | 15 | ||||
| -rw-r--r-- | ld/ld.texi | 13 | ||||
| -rw-r--r-- | ld/ldmain.c | 2 |
13 files changed, 103 insertions, 7 deletions
diff --git a/bfd/ChangeLog b/bfd/ChangeLog index 6543260..741e969 100644 --- a/bfd/ChangeLog +++ b/bfd/ChangeLog @@ -1,3 +1,8 @@ +2020-06-15 Roland McGrath <mcgrathr@google.com> + + * elflink.c (bfd_elf_define_start_stop): Use start_stop_visibility + field of bfd_link_info. + 2020-06-15 Alan Modra <amodra@gmail.com> * config.bfd: Obsolete powerpcle-*-pe targets. @@ -346,7 +351,7 @@ (aout_link_add_symbols): e517df3dbf7 PR 19629 - Check for out of range string table offsets. 531336e3a0b PR 20909 - Fix off-by-one error in check for an - illegal string offset. + illegal string offset. (aout_link_includes_newfunc): Add comment. (pdp11_aout_link_input_section): ad756e3f9e6 - Return with an error on unexpected relocation type rather than ASSERT. diff --git a/bfd/elflink.c b/bfd/elflink.c index ac00f29..14d8d15 100644 --- a/bfd/elflink.c +++ b/bfd/elflink.c @@ -14837,7 +14837,8 @@ bfd_elf_define_start_stop (struct bfd_link_info *info, else { if (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT) - h->other = (h->other & ~ELF_ST_VISIBILITY (-1)) | STV_PROTECTED; + h->other = ((h->other & ~ELF_ST_VISIBILITY (-1)) + | info->start_stop_visibility); if (was_dynamic) bfd_elf_link_record_dynamic_symbol (info, h); } diff --git a/gold/ChangeLog b/gold/ChangeLog index f3d3715..1f9c523 100644 --- a/gold/ChangeLog +++ b/gold/ChangeLog @@ -1,3 +1,15 @@ +2020-06-15 Roland McGrath <mcgrathr@google.com> + + Implement -z start-stop-visibility=... option. + * options.h (class General_options): Handle -z start-stop-visibility=. + (General_options::start_stop_visibility_enum): New public method. + (General_options::set_start_stop_visibility_enum): New private method. + (General_options::start_stop_visibility_enum_): New private member. + * options.cc (General_options::General_options): Add initializer. + (General_options::finalize): Set this->start_stop_visibility_enum_ + from string value. + * layout.cc (Layout::define_section_symbols): Use option setting. + 2020-06-06 Alan Modra <amodra@gmail.com> * powerpc.cc: Update throughout for reloc renaming. diff --git a/gold/layout.cc b/gold/layout.cc index be437f3..b3b0c57 100644 --- a/gold/layout.cc +++ b/gold/layout.cc @@ -2474,6 +2474,7 @@ Layout::create_initial_dynamic_sections(Symbol_table* symtab) void Layout::define_section_symbols(Symbol_table* symtab) { + const elfcpp::STV visibility = parameters->options().start_stop_visibility_enum(); for (Section_list::const_iterator p = this->section_list_.begin(); p != this->section_list_.end(); ++p) @@ -2495,7 +2496,7 @@ Layout::define_section_symbols(Symbol_table* symtab) 0, // symsize elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL, - elfcpp::STV_PROTECTED, + visibility, 0, // nonvis false, // offset_is_from_end true); // only_if_ref @@ -2508,7 +2509,7 @@ Layout::define_section_symbols(Symbol_table* symtab) 0, // symsize elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL, - elfcpp::STV_PROTECTED, + visibility, 0, // nonvis true, // offset_is_from_end true); // only_if_ref diff --git a/gold/options.cc b/gold/options.cc index 94867b3..b13ae71 100644 --- a/gold/options.cc +++ b/gold/options.cc @@ -997,7 +997,8 @@ General_options::General_options() fix_v4bx_(FIX_V4BX_NONE), endianness_(ENDIANNESS_NOT_SET), discard_locals_(DISCARD_SEC_MERGE), - orphan_handling_enum_(ORPHAN_PLACE) + orphan_handling_enum_(ORPHAN_PLACE), + start_stop_visibility_enum_(elfcpp::STV_PROTECTED) { // Turn off option registration once construction is complete. gold::options::ready_to_register = false; @@ -1169,6 +1170,19 @@ General_options::finalize() this->set_orphan_handling_enum(ORPHAN_ERROR); } + // Parse the -z start-stop-visibility argument. + if (this->user_set_start_stop_visibility()) + { + if (strcmp(this->start_stop_visibility(), "default") == 0) + this->set_start_stop_visibility_enum(elfcpp::STV_DEFAULT); + else if (strcmp(this->start_stop_visibility(), "internal") == 0) + this->set_start_stop_visibility_enum(elfcpp::STV_INTERNAL); + else if (strcmp(this->start_stop_visibility(), "hidden") == 0) + this->set_start_stop_visibility_enum(elfcpp::STV_HIDDEN); + else if (strcmp(this->start_stop_visibility(), "protected") == 0) + this->set_start_stop_visibility_enum(elfcpp::STV_PROTECTED); + } + // -M is equivalent to "-Map -". if (this->print_map() && !this->user_set_Map()) { diff --git a/gold/options.h b/gold/options.h index b2059d9..f0e9fbd 100644 --- a/gold/options.h +++ b/gold/options.h @@ -1500,6 +1500,11 @@ class General_options N_("Don't mark variables read-only after relocation")); DEFINE_uint64(stack_size, options::DASH_Z, '\0', 0, N_("Set PT_GNU_STACK segment p_memsz to SIZE"), N_("SIZE")); + DEFINE_enum(start_stop_visibility, options::DASH_Z, '\0', "protected", + N_("ELF symbol visibility for synthesized " + "__start_* and __stop_* symbols"), + ("[default,internal,hidden,protected]"), + {"default", "internal", "hidden", "protected"}); DEFINE_bool(text, options::DASH_Z, '\0', false, N_("Do not permit relocations in read-only segments"), N_("Permit relocations in read-only segments")); @@ -1750,6 +1755,10 @@ class General_options orphan_handling_enum() const { return this->orphan_handling_enum_; } + elfcpp::STV + start_stop_visibility_enum() const + { return this->start_stop_visibility_enum_; } + private: // Don't copy this structure. General_options(const General_options&); @@ -1809,6 +1818,10 @@ class General_options set_orphan_handling_enum(Orphan_handling value) { this->orphan_handling_enum_ = value; } + void + set_start_stop_visibility_enum(elfcpp::STV value) + { this->start_stop_visibility_enum_ = value; } + // These are called by finalize() to set up the search-path correctly. void add_to_library_path_with_sysroot(const std::string& arg) @@ -1876,6 +1889,8 @@ class General_options std::vector<Position_dependent_options*> options_stack_; // Orphan handling option, decoded to an enum value. Orphan_handling orphan_handling_enum_; + // Symbol visibility for __start_* / __stop_* magic symbols. + elfcpp::STV start_stop_visibility_enum_; }; // The position-dependent options. We use this to store the state of diff --git a/include/ChangeLog b/include/ChangeLog index 248866c..f30e5e2 100644 --- a/include/ChangeLog +++ b/include/ChangeLog @@ -1,3 +1,7 @@ +2020-06-12 Roland McGrath <mcgrathr@google.com> + + * bfdlink.h (struct bfd_link_info): New field start_stop_visibility. + 2020-06-12 Nelson Chu <nelson.chu@sifive.com> * opcode/riscv-opc.h: Update the defined versions of CSR from diff --git a/include/bfdlink.h b/include/bfdlink.h index 34a0d2e..7163433 100644 --- a/include/bfdlink.h +++ b/include/bfdlink.h @@ -542,10 +542,10 @@ struct bfd_link_info Normally these optimizations are disabled by default but some targets prefer to enable them by default. So this field is a tri-state variable. The values are: - + zero: Enable the optimizations (either from --relax being specified on the command line or the backend's before_allocation emulation function. - + positive: The user has requested that these optimizations be disabled. (Via the --no-relax command line option). @@ -649,6 +649,9 @@ struct bfd_link_info /* May be used to set DT_FLAGS_1 for ELF. */ bfd_vma flags_1; + /* May be used to set ELF visibility for __start_* / __stop_. */ + unsigned int start_stop_visibility; + /* Start and end of RELRO region. */ bfd_vma relro_start, relro_end; diff --git a/ld/ChangeLog b/ld/ChangeLog index c6de044..6700e72 100644 --- a/ld/ChangeLog +++ b/ld/ChangeLog @@ -1,3 +1,11 @@ +2020-06-15 Roland McGrath <mcgrathr@google.com> + + * NEWS: Mention -z start-stop-visibility=... option for ELF. + * ld.texi (Options): Document -z start-stop-visibility=... option. + * ldmain.c (main): Initialize link_info.start_stop_visibility. + * emultempl/elf.em (gld${EMULATION_NAME}_handle_option): + Parse -z start-stop-visibility=... option. + 2020-06-15 Alan Modra <amodra@gmail.com> * testsuite/ld-scripts/include.exp: Don't load ld-lib.exp. @@ -25,6 +25,9 @@ searched relative to the directory of the linker script before other search paths. +* Add ELF linker command-line option `-z start-stop-visibility=...' to control + the visibility of synthetic `__start_SECNAME` and `__stop_SECNAME` symbols. + Changes in 2.34: * The ld check for "PHDR segment not covered by LOAD segment" is more diff --git a/ld/emultempl/elf.em b/ld/emultempl/elf.em index c4979eb..c577e8b 100644 --- a/ld/emultempl/elf.em +++ b/ld/emultempl/elf.em @@ -749,6 +749,21 @@ fragment <<EOF { link_info.flags_1 |= DF_1_GLOBAUDIT; } + else if (CONST_STRNEQ (optarg, "start-stop-visibility=")) + { + if (strcmp (optarg, "start-stop-visibility=default") == 0) + link_info.start_stop_visibility = STV_DEFAULT; + else if (strcmp (optarg, "start-stop-visibility=internal") == 0) + link_info.start_stop_visibility = STV_INTERNAL; + else if (strcmp (optarg, "start-stop-visibility=hidden") == 0) + link_info.start_stop_visibility = STV_HIDDEN; + else if (strcmp (optarg, "start-stop-visibility=protected") == 0) + link_info.start_stop_visibility = STV_PROTECTED; + else + einfo (_("%F%P: invalid visibility in \`-z %s'; " + "must be default, internal, hidden, or protected"), + optarg); + } EOF if test x"$GENERATE_SHLIB_SCRIPT" = xyes; then @@ -1373,6 +1373,19 @@ Specify a stack size for an ELF @code{PT_GNU_STACK} segment. Specifying zero will override any default non-zero sized @code{PT_GNU_STACK} segment creation. +@item start-stop-visibility=@var{value} +@cindex visibility +@cindex ELF symbol visibility +Specify the ELF symbol visibility for synthesized +@code{__start_SECNAME} and @code{__stop_SECNAME} symbols (@pxref{Input +Section Example}). @var{value} must be exactly @samp{default}, +@samp{internal}, @samp{hidden}, or @samp{protected}. If no @samp{-z +start-stop-visibility} option is given, @samp{protected} is used for +compatibility with historical practice. However, it's highly +recommended to use @samp{-z start-stop-visibility=hidden} in new +programs and shared libraries so that these symbols are not exported +between shared objects, which is not usually what's intended. + @item text @itemx notext @itemx textoff diff --git a/ld/ldmain.c b/ld/ldmain.c index e2c559e..b0ce69f 100644 --- a/ld/ldmain.c +++ b/ld/ldmain.c @@ -27,6 +27,7 @@ #include "bfdlink.h" #include "ctf-api.h" #include "filenames.h" +#include "elf/common.h" #include "ld.h" #include "ldmain.h" @@ -307,6 +308,7 @@ main (int argc, char **argv) #ifdef DEFAULT_NEW_DTAGS link_info.new_dtags = DEFAULT_NEW_DTAGS; #endif + link_info.start_stop_visibility = STV_PROTECTED; ldfile_add_arch (""); emulation = get_emulation (argc, argv); |