* update to the new cache hash API
* std.Target defaultVersionRange moves to std.Target.Os.Tag
* std.Target.Os gains getVersionRange which returns a tagged union
* start the process of splitting Module into Compilation and "zig
module".
- The parts of Module having to do with only compiling zig code are
extracted into ZigModule.zig.
- Next step is to rename Module to Compilation.
- After that rename ZigModule back to Module.
* implement proper cache hash usage when compiling C objects, and
properly manage the file lock of the build artifacts.
* make versions optional to match recent changes to master branch.
* proper cache hash integration for compiling zig code
* proper cache hash integration for linking even when not compiling zig
code.
* ELF LLD linking integrates with the caching system. A comment from
the source code:
Here we want to determine whether we can save time by not invoking LLD when the
output is unchanged. None of the linker options or the object files that are being
linked are in the hash that namespaces the directory we are outputting to. Therefore,
we must hash those now, and the resulting digest will form the "id" of the linking
job we are about to perform.
After a successful link, we store the id in the metadata of a symlink named "id.txt" in
the artifact directory. So, now, we check if this symlink exists, and if it matches
our digest. If so, we can skip linking. Otherwise, we proceed with invoking LLD.
* implement disable_c_depfile option
* add tracy to a few more functions
During codegen we do not yet know the indexes that will be used for
called functions. Therefore, we store the offset into the in-memory
code where the index is needed with a pointer to the Decl and use this
data to insert the proper indexes while writing the binary in the flush
function.
Exports now have a dirty flag and are rewritten on flush if this flag
has been set.
A couple other minor changes have been made based on Andrew's review.
Thus far, we only generate the type, function, export, and code
sections. These are sufficient to generate and export simple functions.
Codegen is currently hardcoded to `i32.const 42`, the main goal of this
commit is to create infrastructure for the container format which will
work with incremental compilation.
