* @enumTagName renamed to @tagName and it works on enums and
union-enums
* Remove the EnumTag type. Now there is only enum and union,
and the tag type of a union is always an enum.
* unions support specifying the tag enum type, and they support
inferring an enum tag type.
* Enums no longer support field types but they do support
setting the tag values. Likewise union-enums when inferring
an enum tag type support setting the tag values.
* It is now an error for enums and unions to have 0 fields.
* switch statements support union-enums
closes#618
* remove `@setGlobalAlign`
* add align keyword for setting alignment on functions and
variables.
* loads and stores use alignment from pointer
* memcpy, memset use alignment from pointer
* add syntax for pointer alignment
* slices can have volatile
* add u2, i2 primitives
* ignore preferred align and use abi align everywhere
* back to only having alignOf builtin.
preferredAlignOf is too tricky to be useful.
See #432. Partial revert of
e726925e80.
See #37
Before, if you did something like:
```
const hi1 = "hi";
const hi2 = hi1;
```
This would create the "hi" data twice in the built object.
But since the value is const we don't have to duplicate the
data, now we take advantage of this fact.
closes#336
* add ability to add assembly files when building an exe, obj, or lib
* add implicit cast from `[N]T` to `?[]const T` (closes#343)
* remove link_exe and link_lib in favor of allowing build_exe and
build_lib support no root zig source file
* introduce zigrt file. it contains only weak symbols so that
multiple instances can be merged. it contains __zig_panic
so that multiple .o files can call the same panic function.
* remove `@setFnVisible` builtin and add @setGlobalLinkage builtin
which is more powerful
* add `@panic` builtin function.
* fix collision of symbols with extern prototypes and internal
function names
* add stack protector safety when linking against libc. To add
the safety mechanism without libc requires implementing
Thread Local Storage. See #276
adds compile error when passing pointer that is byte-aligned
at the beginning but not the end to a function expecting
a fully byte aligned pointer
closes#261
