Revision History

New values introduced for ELF header e_machine field.
Revised language for EI_OSABI and EI_ABIVERSION fields of the ELF header e_ident array.
New section flags SHF_MERGE and SHF_STRINGS added.
New values added to a symbol table entry's st_other field to describe a symbol's visibility.
New dynamic section tags DT_RUNPATH and DT_FLAGS added. Dynamic section tag DT_RPATH moved to level 2.
New semantics for shared object path searching, including new ``Substitution Sequences''.

A new symbol type, STT_COMMON, has been added.
Added language restricting the types of objects that may contain symbols with the section index SHN_COMMON.
Dynamic section entries DT_SYMBOLIC, DT_TEXTREL and DT_BIND_NOW have been moved to level 2. New DT_FLAGS values DF_SYMBOLIC, DF_TEXTREL and DF_BIND_NOW have been added as replacements.
New rules for interpreting dynamic section tag encodings have been added.
The OS and processor specific ranges for DT_FLAGS have been removed.
The language motivating the use of DF_ORIGIN has been changed.

New language has been added warning about the use of WEAK symbols in application programs.
New rules have been defined for composition of consecutive relocation entries that reference the same location.
Language has been added clarifying the order of execution for functions specified by initialization and termination arrays.

New section types and section names added for init arrays, fini arrays and pre-init arrays.
An object may now have both DT_INIT and DT_INIT_ARRAY entries (and both DT_FINI and DT_FINI_ARRAY entries). The relative execution order is specified.
The language describing the order of execution for termination functions has been revised.
A new pre-initialization mechanism has been added.
It is now up to the processor supplement for each processor to specify whether the dynamic linker must invoke the executable file's init and fini routines.

Changed the numbering of some new section types previously added to account for type numbers already in use in particular vendor implementations.
Increased the number of section flag bits available in the OS specific range.

Changed the values used for some new section attribute flags to accommodate platforms already using previously assigned values.
Added new section attribute flags SHF_INFO_LINK, SHF_LINK_ORDER and SHF_OS_NONCONFORMING
Added rules for linkers when linking sections with unrecognized types or flags.

Added language clarifying the semantics of symbols marked as STV_PROTECTED.
Added language clarifying the contents of the initialization and termination arrays.

Added a sentence spelling out the behavior when resolving a symbol to a STV_PROTECTED definition from a shared object.
Added support for more than 65,000 sections in the ELF header, and with SHT_SYMTAB_SHNDX sections, and in symbol tables.

Updated table of EM_* entries.
Added GRP_MASKOS and GRP_MASKPROC. Changed section group description in a few ways, clarifying some fuzzy points and rewriting the rules for symbols referencing into section groups.
Changed the warning about using weak to be stronger.
Reworded the EI_OSABI byte description to make is use clearer.
Added the table of now generic EI_OSABI values.
Added SHF_TLS, PT_TLS and its contents, DF_STATIC_TLS, STT_TLS, .tbss, and .tdata.
Changed the rules for SHT_SYMTAB_SHNDX contents to require 0 when the corresponding st_shndx field is not SHN_XINDEX.