- Split static recipes to depend file.
- Modify makefile configurations in the block to `create_makefile`.
- Expand rust sources in extconf.rb instead of GNU make extension.
TODO: pass `CARGO_TARGET_DIR` without shell syntax.
This commit adds extconf.rb for both the default GC and and MMTk to build
the external GC. This allows common.mk to not need to contain any
implementation-specific build configuration.
db6a29b4a9