From dbfefbdc3aeec88868cb9d46267f91dc62461226 Mon Sep 17 00:00:00 2001 From: Szabolcs Nagy Date: Wed, 1 Apr 2020 16:02:03 +0100 Subject: Rewrite abi-note.S in C. Using C code allows the compiler to add target specific object file markings based on CFLAGS. The arm specific abi-note.S is removed and similar object file fix up will be avoided on AArch64 with standard branch protection. --- csu/abi-note.c | 77 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 77 insertions(+) create mode 100644 csu/abi-note.c (limited to 'csu/abi-note.c') diff --git a/csu/abi-note.c b/csu/abi-note.c new file mode 100644 index 0000000000..8febf4cac0 --- /dev/null +++ b/csu/abi-note.c @@ -0,0 +1,77 @@ +/* Special .init and .fini section support. + Copyright (C) 1997-2020 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + In addition to the permissions in the GNU Lesser General Public + License, the Free Software Foundation gives you unlimited + permission to link the compiled version of this file with other + programs, and to distribute those programs without any restriction + coming from the use of this file. (The Lesser General Public + License restrictions do apply in other respects; for example, they + cover modification of the file, and distribution when not linked + into another program.) + + The GNU C Library 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +/* Define an ELF note identifying the operating-system ABI that the + executable was created for. The ELF note information identifies a + particular OS or coordinated development effort within which the + ELF header's e_machine value plus (for dynamically linked programs) + the PT_INTERP dynamic linker name and DT_NEEDED shared library + names fully identify the runtime environment required by an + executable. + + The general format of ELF notes is as follows. + Offsets and lengths are bytes or (parenthetical references) to the + values in other fields. + +offset length contents +0 4 length of name +4 4 length of data +8 4 note type +12 (0) vendor name + - null-terminated ASCII string, padded to 4-byte alignment +12+(0) (4) note data, + + The GNU project and cooperating development efforts (including the + Linux community) use note type 1 and a vendor name string of "GNU" + for a note descriptor that indicates ABI requirements. The note data + is four 32-bit words. The first of these is an operating system + number (0=Linux, 1=Hurd, 2=Solaris, ...) and the remaining three + identify the earliest release of that OS that supports this ABI. + See abi-tags (top level) for details. */ + +#include +#include +#include +#include /* OS-specific ABI tag value */ + +/* The linker (GNU ld 2.8 and later) recognizes an allocated section whose + name begins with `.note' and creates a PT_NOTE program header entry + pointing at it. */ + +__attribute__ ((used, aligned (4), section (".note.ABI-tag"))) +static const struct +{ + ElfW(Nhdr) nhdr; + char name[4]; + int32_t desc[4]; +} __abi_tag = { + { .n_namesz = sizeof __abi_tag.name, + .n_descsz = sizeof __abi_tag.desc, + .n_type = 1 }, + "GNU", + { __ABI_TAG_OS, __ABI_TAG_VERSION } +}; -- cgit v1.2.3