With libc++ 21 science/mmdb2 fails to build, with errors similar to:
In file included from mmdb2/mmdb_machine_.cpp:41:
mmdb2/mmdb_machine_.h:296:13: error: unknown type name 'size_t'; did you mean 'std::size_t'?
296 | typedef size_t fpstr_size_t;
| ^~~~~~
| std::size_t
/usr/include/c++/v1/__cstddef/size_t.h:20:7: note: 'std::size_t' declared here
20 | using size_t = decltype(sizeof(int));
| ^
This is because mmdb2 apparently relies on transitive includes getting
the declaration of size_t, but with libc++ 21 this no longer works. Add
an include of <stddef.h> to work around it.
PR: 293180
Approved by: maintainer timeout (2 weeks)
MFH: 2026Q1
Dimitry Andric
27612e339b