error: use of undeclared identifier 'assert'

[themightyoarfish]

I'm building current master on macOS 15.1 with Apple Clang 16 like so

git clone https://github.com/koide3/iridescence --recursive && mkdir iridescence/build && cd iridescence/build && cmake .. -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=$HOME/Downloads/tmp-prefix && make && make install

which terminates after a bit with

/Users/rasmus/Downloads/source_builds/iridescence/src/glk/pointcloud_buffer.cpp:120:3: error: use of undeclared identifier 'assert'
  120 |   assert(this->num_points == num_points);

Maybe on linux, #include <cassert> is not needed, but adding it makes this error go away on macos.