This was removed in e465a2b456e7c0aba6aefc1c4b406b8089386d1a erroneously but it still needed on Windows/mingw64 builds. You can view, comment on, or merge this pull request online at:
https://github.com/geany/geany/pull/3600
-- Commit Summary --
* Link to libiconv explicitly for Windows/mingw64 builds
-- File Changes --
M configure.ac (1)
-- Patch Links --
https://github.com/geany/geany/pull/3600.patch https://github.com/geany/geany/pull/3600.diff