* transpose include(mode.common) and include (mode.${build_mode}),
so the former can reference the value defined by the latter.
* set stack_usage_threshold for supported build modes.
please note, this compiler option (-Wstack-usage=<bytes>) is only
supported by GCC so far.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Scylla uses different build mode to customize the build for different
purposes. in this change, instead of having it in a python dictionary,
the customized settings are located in their own files, and loaded
on demand. we don't support multi-config generator yet.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
