On Windows, the command line arguments of a program are a single WTF-16 encoded string and it's up to the program to split it into an array of strings. In C/C++, the entry point of the C runtime takes care of splitting the command line and passing argc/argv to the main function.
https://github.com/ziglang/zig/pull/18309 updated ArgIteratorWindows to match the behavior of CommandLineToArgvW, but it turns out that CommandLineToArgvW's behavior does not match the behavior of the C runtime post-2008. In 2008, the C runtime argv splitting changed how it handles consecutive double quotes within a quoted argument (it's now considered an escaped quote, e.g. `"foo""bar"` post-2008 would get parsed into `foo"bar`), and the rules around argv[0] were also changed.
This commit makes ArgIteratorWindows match the behavior of the post-2008 C runtime, and adds a standalone test that verifies the behavior matches both the MSVC and MinGW argv splitting exactly in all cases (it checks that randomly generated command line strings get split the same way).
The motivation here is roughly the same as when the same change was made in Rust (https://github.com/rust-lang/rust/pull/87580), that is (paraphrased):
- Consistent behavior between Zig and modern C/C++ programs
- Allows users to escape double quotes in a way that can be more straightforward
Additionally, the suggested mitigation for BatBadBut (https://flatt.tech/research/posts/batbadbut-you-cant-securely-execute-commands-on-windows/) relies on the post-2008 argv splitting behavior for roundtripping of the arguments given to `cmd.exe`. Note: it's not necessary for the suggested mitigation to work, but it is necessary for the suggested escaping to be parsed back into the intended argv by ArgIteratorWindows after being run through a `.bat` file.
This adds the *std.Build owner to LazyPath so that lazy paths returned
from a dependency can be used in the application without friction or
footguns.
closes#19313
There is no way to know the expected parent pointer attributes (most
notably alignment) from the type of the field pointer, so provide them
in the first argument.
This commit also performs some refactors to `TypedValue.print` in
preparation for improved comptime pointer access logic. Once that logic
exists, `TypedValue.print` can use Sema to access pointers for more
helpful printing.
This commit also implements proposal #19435, because the existing logic
there relied on some blatantly incorrect code in `Value.sliceLen`.
Resolves: #19435
This test has regressed due to a bug in the self-hosted COFF linker.
Jakub recommended disabling it for now, since the COFF linker is being
effectively rewritten, so there is little point in fixing the bug now.
This commit changes how we represent comptime-mutable memory
(`comptime var`) in the compiler in order to implement the intended
behavior that references to such memory can only exist at comptime.
It does *not* clean up the representation of mutable values, improve the
representation of comptime-known pointers, or fix the many bugs in the
comptime pointer access code. These will be future enhancements.
Comptime memory lives for the duration of a single Sema, and is not
permitted to escape that one analysis, either by becoming runtime-known
or by becoming comptime-known to other analyses. These restrictions mean
that we can represent comptime allocations not via Decl, but with state
local to Sema - specifically, the new `Sema.comptime_allocs` field. All
comptime-mutable allocations, as well as any comptime-known const allocs
containing references to such memory, live in here. This allows for
relatively fast checking of whether a value references any
comptime-mtuable memory, since we need only traverse values up to
pointers: pointers to Decls can never reference comptime-mutable memory,
and pointers into `Sema.comptime_allocs` always do.
This change exposed some faulty pointer access logic in `Value.zig`.
I've fixed the important cases, but there are some TODOs I've put in
which are definitely possible to hit with sufficiently esoteric code. I
plan to resolve these by auditing all direct accesses to pointers (most
of them ought to use Sema to perform the pointer access!), but for now
this is sufficient for all realistic code and to get tests passing.
This change eliminates `Zcu.tmp_hack_arena`, instead using the Sema
arena for comptime memory mutations, which is possible since comptime
memory is now local to the current Sema.
This change should allow `Decl` to store only an `InternPool.Index`
rather than a full-blown `ty: Type, val: Value`. This commit does not
perform this refactor.
