Conflicts:
* lib/std/zig/ast.zig
* lib/std/zig/parse.zig
* lib/std/zig/parser_test.zig
* lib/std/zig/render.zig
* src/Module.zig
* src/zir.zig
I resolved some of the conflicts by reverting a small portion of
@tadeokondrak's stage2 logic here regarding `callconv(.Inline)`.
It will need to get reworked as part of this branch.
b4e344bcf8