From: Nick Clifton Date: Mon, 14 May 2018 14:32:43 +0000 (+0100) Subject: Stop generating GNU build notes for linkonce sections. X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=864bb26cb34ce6f0a85f83ed38757d5512d07b2a;p=binutils-gdb.git Stop generating GNU build notes for linkonce sections. gas * write.c (maybe_generate_build_notes): Generate notes on a per-code-section basis. Skip linkonce sections. ld * testsuite/ld-elf/notes.exp: New file: Run new test. * testsuite/ld-elf/note1_1.s: New file: Source file for test. * testsuite/ld-elf/note1_2.s: New file: Source file for test. * testsuite/ld-elf/note1.r: New file: Expected readelf output. --- diff --git a/gas/ChangeLog b/gas/ChangeLog index 8322ccf4e79..358f033fd58 100644 --- a/gas/ChangeLog +++ b/gas/ChangeLog @@ -1,3 +1,8 @@ +2018-05-14 Nick Clifton + + * write.c (maybe_generate_build_notes): Generate notes on a + per-code-section basis. Skip linkonce sections. + 2018-05-14 Nick Clifton PR 23153 diff --git a/gas/write.c b/gas/write.c index b902bf85659..39c894a8e68 100644 --- a/gas/write.c +++ b/gas/write.c @@ -1946,6 +1946,7 @@ maybe_generate_build_notes (void) segT sec; char * note; offsetT note_size; + offsetT total_size; offsetT desc_size; offsetT desc2_offset; int desc_reloc; @@ -1963,7 +1964,8 @@ maybe_generate_build_notes (void) SEC_READONLY | SEC_HAS_CONTENTS | SEC_DATA); bfd_set_section_alignment (stdoutput, sec, 2); - /* Create a version note. */ + /* Work out the size of the notes that we will create, + and the relocation we should use. */ if (bfd_arch_bits_per_address (stdoutput) <= 32) { note_size = 28; @@ -1997,65 +1999,59 @@ maybe_generate_build_notes (void) desc_reloc = BFD_RELOC_64; } - frag_now_fix (); - note = frag_more (note_size); - memset (note, 0, note_size); + /* We have to create a note for *each* code section. + Linker garbage collection might discard some. */ + total_size = 0; + note = NULL; - if (target_big_endian) - { - note[3] = 8; /* strlen (name) + 1. */ - note[7] = desc_size; /* Two 8-byte offsets. */ - note[10] = NT_GNU_BUILD_ATTRIBUTE_OPEN >> 8; - note[11] = NT_GNU_BUILD_ATTRIBUTE_OPEN & 0xff; - } - else - { - note[0] = 8; /* strlen (name) + 1. */ - note[4] = desc_size; /* Two 8-byte offsets. */ - note[8] = NT_GNU_BUILD_ATTRIBUTE_OPEN & 0xff; - note[9] = NT_GNU_BUILD_ATTRIBUTE_OPEN >> 8; - } - - /* The a1 version number indicates that this note was - generated by the assembler and not the gcc annobin plugin. */ - memcpy (note + 12, "GA$3a1", 8); - - /* Find the first code section symbol. */ for (sym = symbol_rootP; sym != NULL; sym = sym->sy_next) if (sym->bsym != NULL && sym->bsym->flags & BSF_SECTION_SYM && sym->bsym->section != NULL - && sym->bsym->section->flags & SEC_CODE) + /* Skip linkonce sections - we cannot these section symbols as they may disappear. */ + && (sym->bsym->section->flags & (SEC_CODE | SEC_LINK_ONCE)) == SEC_CODE + /* Not all linkonce sections are flagged... */ + && strncmp (S_GET_NAME (sym), ".gnu.linkonce", sizeof ".gnu.linkonce" - 1) != 0) { - /* Found one - now create a relocation against this symbol. */ - create_note_reloc (sec, sym, 20, desc_reloc, 0, note); - break; - } + /* Create a version note. */ + frag_now_fix (); + note = frag_more (note_size); + memset (note, 0, note_size); - /* Find the last code section symbol. */ - if (sym) - { - for (sym = symbol_lastP; sym != NULL; sym = sym->sy_previous) - if (sym->bsym != NULL - && sym->bsym->flags & BSF_SECTION_SYM - && sym->bsym->section != NULL - && sym->bsym->section->flags & SEC_CODE) + if (target_big_endian) { - /* Create a relocation against the end of this symbol. */ - create_note_reloc (sec, sym, desc2_offset, desc_reloc, - bfd_get_section_size (sym->bsym->section), - note); - break; + note[3] = 8; /* strlen (name) + 1. */ + note[7] = desc_size; /* Two 8-byte offsets. */ + note[10] = NT_GNU_BUILD_ATTRIBUTE_OPEN >> 8; + note[11] = NT_GNU_BUILD_ATTRIBUTE_OPEN & 0xff; + } + else + { + note[0] = 8; /* strlen (name) + 1. */ + note[4] = desc_size; /* Two 8-byte offsets. */ + note[8] = NT_GNU_BUILD_ATTRIBUTE_OPEN & 0xff; + note[9] = NT_GNU_BUILD_ATTRIBUTE_OPEN >> 8; } - } - /* else - if we were unable to find any code section symbols then - probably there is no code in the output. So leaving the start - and end values as zero in the note is OK. */ - /* FIXME: Maybe add a note recording the assembler command line and version ? */ + /* The a1 version number indicates that this note was + generated by the assembler and not the gcc annobin plugin. */ + memcpy (note + 12, "GA$3a1", 8); + + /* Create a relocation to install the start address of the note... */ + create_note_reloc (sec, sym, 20, desc_reloc, 0, note); + + /* ...and another one to install the end address. */ + create_note_reloc (sec, sym, desc2_offset, desc_reloc, + bfd_get_section_size (sym->bsym->section), + note); + + total_size += note_size; + /* FIXME: Maybe add a note recording the assembler command line and version ? */ + } /* Install the note(s) into the section. */ - bfd_set_section_contents (stdoutput, sec, (bfd_byte *) note, 0, note_size); + if (total_size) + bfd_set_section_contents (stdoutput, sec, (bfd_byte *) note, 0, total_size); subsegs_finish_section (sec); relax_segment (seg_info (sec)->frchainP->frch_root, sec, 0); size_seg (stdoutput, sec, NULL); diff --git a/ld/ChangeLog b/ld/ChangeLog index fbc4d59898c..bb20a460c26 100644 --- a/ld/ChangeLog +++ b/ld/ChangeLog @@ -1,3 +1,10 @@ +2018-05-14 Nick Clifton + + * testsuite/ld-elf/notes.exp: New file: Run new test. + * testsuite/ld-elf/note1_1.s: New file: Source file for test. + * testsuite/ld-elf/note1_2.s: New file: Source file for test. + * testsuite/ld-elf/note1.r: New file: Expected readelf output. + 2018-05-14 H.J. Lu PR ld/23169 diff --git a/ld/testsuite/ld-elf/note1.r b/ld/testsuite/ld-elf/note1.r new file mode 100644 index 00000000000..58886d8b47a --- /dev/null +++ b/ld/testsuite/ld-elf/note1.r @@ -0,0 +1,6 @@ +#... +Displaying notes found in: .gnu.build.attributes +[ ]+Owner[ ]+Data size[ ]+Description +[ ]+GA\$3a1[ ]+0x000000(08|10)[ ]+OPEN[ ]+Applies to region from 0.* +[ ]+GA\$3a1[ ]+0x000000(08|10)[ ]+OPEN[ ]+Applies to region from 0.* +#pass diff --git a/ld/testsuite/ld-elf/note1_1.s b/ld/testsuite/ld-elf/note1_1.s new file mode 100644 index 00000000000..e9d80fb2789 --- /dev/null +++ b/ld/testsuite/ld-elf/note1_1.s @@ -0,0 +1,17 @@ + .section .gnu.linkonce.t.thunk.ax,"ax",%progbits + .globl thunk.ax + .hidden thunk.ax + .p2align 4 + .type thunk.ax,%function +thunk.ax: + .dc.l 0 + .size thunk.ax, . - thunk.ax + + .p2align 4 + .globl foo + .type foo,%function +foo: + .dc.a thunk.ax + .dc.l 0 + .size foo, . - foo + diff --git a/ld/testsuite/ld-elf/note1_2.s b/ld/testsuite/ld-elf/note1_2.s new file mode 100644 index 00000000000..8162d38db50 --- /dev/null +++ b/ld/testsuite/ld-elf/note1_2.s @@ -0,0 +1,17 @@ + + .section .gnu.linkonce.t.thunk.ax,"ax",%progbits + .globl thunk.ax + .hidden thunk.ax + .p2align 4 + .type thunk.ax,%function +thunk.ax: + .dc.l 0 + .size thunk.ax, . - thunk.ax + + .p2align 4 + .globl bar + .type bar,%function +bar: + .dc.a thunk.ax + .dc.l 0 + .size bar, . - bar diff --git a/ld/testsuite/ld-elf/notes.exp b/ld/testsuite/ld-elf/notes.exp new file mode 100644 index 00000000000..5f55d463935 --- /dev/null +++ b/ld/testsuite/ld-elf/notes.exp @@ -0,0 +1,43 @@ +# Expect script for various ELF based Note tests. +# Copyright (C) 2018 Free Software Foundation, Inc. +# +# This file is part of the GNU Binutils. +# +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 3 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program; if not, write to the Free Software +# Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, +# MA 02110-1301, USA. +# + +# Exclude non-ELF targets. + +if ![is_elf_format] { + return +} + +set old_ldflags $LDFLAGS +if { [istarget spu*-*-*] } { + set LDFLAGS "$LDFLAGS --local-store 0:0" +} + +if { [is_remote host] } then { + remote_download host merge.ld +} + +run_ld_link_tests [list \ + [list "Linkonce sections with assembler generated notes" \ + "-r" "" "--generate-missing-build-notes=yes" \ + {note1_1.s note1_2.s} \ + {{readelf {--wide --notes} note1.r}} \ + "note1.so" ] \ +]