The codegen would sometimes change the LLVM type for some constants to
an unnamed structure in order to accomodate extra padding. This is fine
as long as the alignment of each field is still respected and it was not
the case for structure types, leading to ill-formed constants being
generated.
Optional types suffer from this to a lower extent as their layout is
quite lucky, the only missing piece was the tail padding.
Closes#4530Closes#4594Closes#4295
Closes my will to live
Before, type_has_one_possible_value would return false for the value
`.{1}`. But actually, that type is a tuple with a single comptime field.
Such a type, in fact, has one possible value.
This plus the corresponding adjustment to get_the_one_possible_value
solves #3878.
Make fallthrough an error when compiler supports it. This requires a new
macro that is defined with such compilers to be used as a statement, at
all fallthrough sites:
switch (...) {
case 0:
...
ZIG_FALLTHROUGH;
case 1:
...
break;
default:
...
break;
}
If we ever move to C++17 as minimal requirement, then the macro can be
replaced with `[[fallthrough]];` at statement sites.
* Don't add an extra slot for the sentinel. Most of the code keeps using
the constant value from the type descriptor, let's harmonize all the
code dealing with sentinels.
* Properly write out sentinel values when reinterpreting pointers at
comptime.
* Allow the reading of the 0th element in a `[0:S]T` type.
* Fix codegen for optional types that decay to a pointer, the type
behaves as a boolean
* Fix comptime evaluation of zero-sized arrays, always initialize the
internal array elements
Closes#4673
Now it will emit a compile error rather than crashing when the child
type has not been resolved properly.
Introduces `get_optional_type2` which should be used generally inside
ir.cpp.
Fix some std lib compile errors noticed by the provided test case.
Thanks @LemonBoy for the test case. Closes#4377.
Fixes#4374.
And fix most of the fallout. This also makes optional pointers not
require resolving zero bits, because the comptime value struct layout no
longer depends on whether the type has zero bits.
Thanks to @LemonBoy for the behavior test case
Closes#4357Closes#4359
- split util_base.hpp from util.hpp
- new namespaces: `mem` and `heap`
- new `mem::Allocator` interface
- new `heap::CAllocator` impl with global `heap::c_allocator`
- new `heap::ArenaAllocator` impl
- new `mem::TypeInfo` extracts names without RTTI
- name extraction is enabled w/ ZIG_ENABLE_MEM_PROFILE=1
- new `mem::List` takes explicit `Allocator&` parameter
- new `mem::HashMap` takes explicit `Allocator&` parameter
- add Codegen.pass1_arena and use for all `ZigValue` allocs
- deinit Codegen.pass1_arena early in `zig_llvm_emit_output()`
