Support incremental scanning of sources
@ebassi
Submitted by Emmanuele Bassi Link to original bug (#782188)
Description
Currently, we scan all sources, all the time, to generate the introspection data. While this sounds fine when your build system takes 15 minutes to build your project from scratch, and 2 minutes when you just touch a C file, it's a bit less fine when your build system takes 2 minutes to build from scratch, and 8 seconds when you just touch a C file — see: http://mesonbuild.com
Currently, incrementally building GTK+ 3.91 with Meson after touching a since C file takes about 20 second, of which more than half are taken by the introspection data scanning.
One way to avoid that would be to scan each source file, generate partial introspection data, and then combine everything at the end.