`std.mem.Allocator.createOne` is renamed to `std.mem.Allocator.create`.
The problem with the previous API is that even after copy elision,
the initalization value passed as a parameter would always be a copy.
With the new API, once copy elision is done, initialization
functions can directly initialize allocated memory in place.
Related:
* #1872
* #1873
This commit contains everything from the copy-elision-2
branch that does not have to do with copy elision directly,
but is generally useful for master branch.
* All const values know their parents, when applicable, not
just structs and unions.
* Null pointers in const values are represented explicitly,
rather than as a HardCodedAddr value of 0.
* Rename "maybe" to "optional" in various code locations.
* Separate DeclVarSrc and DeclVarGen
* Separate PtrCastSrc and PtrCastGen
* Separate CmpxchgSrc and CmpxchgGen
* Represent optional error set as an integer, using the 0 value.
In a const value, it uses nullptr.
* Introduce type_has_one_possible_value and use it where applicable.
* Fix debug builds not setting memory to 0xaa when storing
undefined.
* Separate the type of a variable from the const value of a variable.
* Use copy_const_val where appropriate.
* Rearrange structs to pack data more efficiently.
* Move test/cases/* to test/behavior/*
* Use `std.debug.assertOrPanic` in behavior tests instead of
`std.debug.assert`.
* Fix outdated slice syntax in docs.
* error.BadFd is not a valid error code. it would always be a bug to
get this error code.
* merge error.Io with existing error.InputOutput
* merge error.PathNotFound with existing error.FileNotFound.
Not all OS's support both.
* add os.File.openReadC
* add error.BadPathName for windows file operations with invalid
characters
* add os.toPosixPath to help stack allocate a null terminating byte
* add some TODOs for other functions to investigate removing the
allocator requirement
* optimize some implementations to use the alternate functions when
a null byte is already available
* add a missing error.SkipZigTest
* os.selfExePath uses a non-allocating API
* os.selfExeDirPath uses a non-allocating API
* os.path.real uses a non-allocating API
* add os.path.realAlloc and os.path.realC
* convert many windows syscalls to use the W versions (See #534)
* add std.event.RwLock and std.event.RwLocked
* std.debug.warn does its printing locked
* add std.Mutex, however it's currently implemented as a spinlock
* rename std.event.Group.cancelAll to std.event.Group.deinit and change
the docs and assumptions.
* add std.HashMap.clone