I took a risk that docker had implemented namespacing with regards to
architectures correctly, but of course they didn't. So the CI docker
image for x86_64 was clobbered by an aarch64 image with the same name.
Now we're doing arch namespaces with the tag name, so here's the x86_64
one.
Clang does not support -march=native for all targets.
Arguably it should always work, but in reality it gives:
error: the clang compiler does not support '-march=native'
If we move CPU detection logic into Zig itelf, we will not need this,
instead we will always pass target features and CPU configuration explicitly.
For now, we simply avoid passing the flag when it is known to not be
supported.
It had the downside of running all the comptime blocks and resolving
all the usingnamespaces of each system, when just trying to discover if
the current system is a particular one.
For Darwin, where it's nice to use `std.Target.current.isDarwin()`, this
demonstrates the utility that #425 would provide.
* All the data types from `@import("builtin")` are moved to
`@import("std").builtin`. The target-related types are moved
to `std.Target`. This allows the data types to have methods, such as
`std.Target.current.isDarwin()`.
* `std.os.windows.subsystem` is moved to
`std.Target.current.subsystem`.
* Remove the concept of the panic package from the compiler
implementation. Instead, `std.builtin.panic` is always the panic
function. It checks for `@hasDecl(@import("root"), "panic")`,
or else provides a default implementation.
This is an important step for multibuilds (#3028). Without this change,
the types inside the builtin namespace look like different types, when
trying to merge builds with different target settings. With this change,
Zig can figure out that, e.g., `std.builtin.Os` (the enum type) from one
compilation and `std.builtin.Os` from another compilation are the same
type, even if the target OS value differs.
The sockaddr pointer and size of the accept function points to a data structure that can only be determined at runtime. The only requirement is that it must be large enough to hold 2 bytes for the address family value. Typeical usage of the socket API is for UDP/TCP IPv4 and IPv6 sockets, which use sockaddr_in and sockaddr_in6. And some sockets can actually support both simultaneously in which case the app may want to have access to the size of the returned sockaddr. Operating systems can even support custom protocols where they use custom sockaddr data structures. In this case the standard library would have no knowledge of the actual size of the sockaddr being passed into the accept function. In this case the standard library should defer to the app to pass in the size of their structure.
