tree 579bc3ce6dab48d5452fd735ba3c2d21e574b8a4
parent 65d4479113439e58d8b53d9a1f2cfb14fcdfab81
author Marc Kupietz <kupietz@ids-mannheim.de> 1785479596 +0900
committer Marc Kupietz <kupietz@ids-mannheim.de> 1785479596 +0900

Document the build against the rocksdb of the distribution

The README still asked for the rocksdb 5.11 fork, which is not needed anymore,
and its build recipe did not work: the tests run the collocatordb_query tool,
which is built with the rpath of its install location, so they only pass after
make install, and they find the tool and their data only when the build
directory is build/ inside the sources.

Also documents when a static rocksdb is needed at all - only for linking a
program completely statically, as dereko2vec does, which is worth about 10% on
collocator lookups, measured with rocksdb 7.8.3 which ships both variants.
Debian and Ubuntu ship librocksdb.a, Fedora, Rocky Linux and RHEL do not, so
the README says how to build one without shadowing the packaged headers.

That shadowing is the trap behind the undefined references one gets when a
hand installed rocksdb sits below /usr/local, so the build compares the version
of the headers with the version of the library and stops with an explanation
instead of leaving that to the linker.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Change-Id: Ie79c5a33bfd068a8c3915f368db7d0c45e8d20fb