sysdeps/mips/elf_machine_sym_no_match.h

   1 /* MIPS-specific handling of undefined symbols.
   2    Copyright (C) 2008-2023 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #ifndef _ELF_MACHINE_SYM_NO_MATCH_H
  20 #define _ELF_MACHINE_SYM_NO_MATCH_H
  21
  22 #include <link.h>
  23 #include <stdbool.h>
  24
  25 /* The semantics of zero/non-zero values of undefined symbols differs
  26    depending on whether the non-PIC ABI is in use.  Under the non-PIC
  27    ABI, a non-zero value indicates that there is an address reference
  28    to the symbol and thus it must always be resolved (except when
  29    resolving a jump slot relocation) to the PLT entry whose address is
  30    provided as the symbol's value; a zero value indicates that this
  31    canonical-address behaviour is not required.  Yet under the classic
  32    MIPS psABI, a zero value indicates that there is an address
  33    reference to the function and the dynamic linker must resolve the
  34    symbol immediately upon loading.  To avoid conflict, symbols for
  35    which the dynamic linker must assume the non-PIC ABI semantics are
  36    marked with the STO_MIPS_PLT flag.  */
  37 static inline bool
  38 elf_machine_sym_no_match (const ElfW(Sym) *sym)
  39 {
  40   return sym->st_shndx == SHN_UNDEF && !(sym->st_other & STO_MIPS_PLT);
  41 }
  42
  43 #endif /* _ELF_MACHINE_SYM_NO_MATCH_H */