The GNU documentation is ambiguous about the version index for
unversioned undefined symbols. The current specification at
https://sourceware.org/gnu-gabi/program-loading-and-dynamic-linking.txt
defines VER_NDX_LOCAL (0) as "The symbol is private, and is not
available outside this object."
However, this naming is misleading for undefined symbols. As suggested
in
discussions, VER_NDX_LOCAL should conceptually be VER_NDX_NONE and apply
to unversioned undefined symbols as well.
GNU ld has used index 0 for unversioned undefined symbols both before
version 2.35 (see https://sourceware.org/PR26002) and in the upcoming
2.46 release (see https://sourceware.org/PR33577). This change aligns
with GNU ld's behavior by switching from index 1 to index 0.
While here, add a test to dso-undef-extract-lazy.s that undefined
symbols of index 0 in DSO are treated as unversioned symbols.
d96a93ff00