6a91be8666
Add a -z pack-relative-relocs option to enable DT_RELR and create a relr.dyn section for DT_RELR. DT_RELR is implemented with the linker relaxation infrastructure, but it doesn't require the --relax option enabled. -z pack-relative-relocs implies -z combreloc. -z nocombreloc implies -z nopack-relative-relocs. -z pack-relative-relocs is chosen over the similar option in lld, --pack-dyn-relocs=relr, to implement a glibc binary lockout mechanism with a special glibc version symbol, to avoid random crashes of DT_RELR binaries with the existing glibc binaries. bfd/ * elf-bfd.h (elf_link_hash_table): Add srelrdyn. * elflink.c (_bfd_elf_link_create_dynamic_sections): Create a .relr.dyn section for DT_RELR. include/ * bfdlink.h (bfd_link_info): Add enable_dt_relr. ld/ * News: Mention -z pack-relative-relocs and -z nopack-relative-relocs. * ld.texi: Document -z pack-relative-relocs and -z nopack-relative-relocs. * ldelf.c (ldelf_after_parse): Disable DT_RELR if not building PIE nor shared library. Add 3 spare dynamic tags for DT_RELR, DT_RELRSZ and DT_RELRENT. * ldlang.c (lang_relax_sections): Also enable relaxation if DT_RELR is enabled. * emulparams/elf32_x86_64.sh: Source dt-relr.sh. * emulparams/elf_i386.sh: Likewise. * emulparams/elf_x86_64.sh: Likewise. * emulparams/dt-relr.sh: New file. * scripttempl/elf.sc: Support .relr.dyn.
The files in this directory are linker script templates.
genscripts.sh sets some shell variables, then sources
EMULATION.sc, to generate EMULATION.{x,xr,xu,xn,xbn} -- the script
files for default, -r, -Ur, -n, -N.
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