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2025-06-12compiler: rework emit paths and cache modesmlugg
Previously, various doc comments heavily disagreed with the implementation on both what lives where on the filesystem at what time, and how that was represented in code. Notably, the combination of emit paths outside the cache and `disable_lld_caching` created a kind of ad-hoc "cache disable" mechanism -- which didn't actually *work* very well, 'most everything still ended up in this cache. There was also a long-standing issue where building using the LLVM backend would put a random object file in your cwd. This commit reworks how emit paths are specified in `Compilation.CreateOptions`, how they are represented internally, and how the cache usage is specified. There are now 3 options for `Compilation.CacheMode`: * `.none`: do not use the cache. The paths we have to emit to are relative to the compiler cwd (they're either user-specified, or defaults inferred from the root name). If we create any temporary files (e.g. the ZCU object when using the LLVM backend) they are emitted to a directory in `local_cache/tmp/`, which is deleted once the update finishes. * `.whole`: cache the compilation based on all inputs, including file contents. All emit paths are computed by the compiler (and will be stored as relative to the local cache directory); it is a CLI error to specify an explicit emit path. Artifacts (including temporary files) are written to a directory under `local_cache/tmp/`, which is later renamed to an appropriate `local_cache/o/`. The caller (who is using `--listen`; e.g. the build system) learns the name of this directory, and can get the artifacts from it. * `.incremental`: similar to `.whole`, but Zig source file contents, and anything else which incremental compilation can handle changes for, is not included in the cache manifest. We don't need to do the dance where the output directory is initially in `tmp/`, because our digest is computed entirely from CLI inputs. To be clear, the difference between `CacheMode.whole` and `CacheMode.incremental` is unchanged. `CacheMode.none` is new (previously it was sort of poorly imitated with `CacheMode.whole`). The defined behavior for temporary/intermediate files is new. `.none` is used for direct CLI invocations like `zig build-exe foo.zig`. The other cache modes are reserved for `--listen`, and the cache mode in use is currently just based on the presence of the `-fincremental` flag. There are two cases in which `CacheMode.whole` is used despite there being no `--listen` flag: `zig test` and `zig run`. Unless an explicit `-femit-bin=xxx` argument is passed on the CLI, these subcommands will use `CacheMode.whole`, so that they can put the output somewhere without polluting the cwd (plus, caching is potentially more useful for direct usage of these subcommands). Users of `--listen` (such as the build system) can now use `std.zig.EmitArtifact.cacheName` to find out what an output will be named. This avoids having to synchronize logic between the compiler and all users of `--listen`.
2025-06-12spirv: make the backend compile againmlugg
Unfortunately, the self-hosted SPIR-V backend is quite tightly coupled with the self-hosted SPIR-V linker through its `Object` concept (which is much like `llvm.Object`). Reworking this would be too much work for this branch. So, for now, I have introduced a special case (similar to the LLVM backend's special case) to the codegen logic when using this backend. We will want to delete this special case at some point, but it need not block this work.
2025-06-12wasm: get self-hosted compiling, and supporting `separate_thread`mlugg
My original goal here was just to get the self-hosted Wasm backend compiling again after the pipeline change, but it turned out that from there it was pretty simple to entirely eliminate the shared state between `codegen.wasm` and `link.Wasm`. As such, this commit not only fixes the backend, but makes it the second backend (after CBE) to support the new 1:N:1 threading model.
2025-06-12compiler: get most backends compiling againmlugg
As of this commit, every backend other than self-hosted Wasm and self-hosted SPIR-V compiles and (at least somewhat) functions again. Those two backends are currently disabled with panics. Note that `Zcu.Feature.separate_thread` is *not* enabled for the fixed backends. Avoiding linker references from codegen is a non-trivial task, and can be done after this branch.
2025-06-12compiler: rework backend pipeline to separate codegen and linkmlugg
The idea here is that instead of the linker calling into codegen, instead codegen should run before we touch the linker, and after MIR is produced, it is sent to the linker. Aside from simplifying the call graph (by preventing N linkers from each calling into M codegen backends!), this has the huge benefit that it is possible to parallellize codegen separately from linking. The threading model can look like this: * 1 semantic analysis thread, which generates AIR * N codegen threads, which process AIR into MIR * 1 linker thread, which emits MIR to the binary The codegen threads are also responsible for `Air.Legalize` and `Air.Liveness`; it's more efficient to do this work here instead of blocking the main thread for this trivially parallel task. I have repurposed the `Zcu.Feature.separate_thread` backend feature to indicate support for this 1:N:1 threading pattern. This commit makes the C backend support this feature, since it was relatively easy to divorce from `link.C`: it just required eliminating some shared buffers. Other backends don't currently support this feature. In fact, they don't even compile -- the next few commits will fix them back up.
2025-06-12link: make checking for failed types the responsibility of Compilationmlugg
2025-06-12link: divorce LLD from the self-hosted linkersmlugg
Similar to the previous commit, this commit untangles LLD integration from the self-hosted linkers. Despite the big network of functions which were involved, it turns out what was going on here is quite simple. The LLD linking logic is actually very self-contained; it requires a few flags from the `link.File.OpenOptions`, but that's really about it. We don't need any of the mutable state on `Elf`/`Coff`/`Wasm`, for instance. There was some legacy code trying to handle support for using self-hosted codegen with LLD, but that's not a supported use case, so I've just stripped it out. For now, I've just pasted the logic for linking the 3 targets we currently support using LLD for into this new linker implementation, `link.Lld`; however, it's almost certainly possible to combine some of the logic and simplify this file a bit. But to be honest, it's not actually that bad right now. This commit ends up eliminating the distinction between `flush` and `flushZcu` (formerly `flushModule`) in linkers, where the latter previously meant something along the lines of "flush, but if you're going to be linking with LLD, just flush the ZCU object file, don't actually link"?. The distinction here doesn't seem like it was properly defined, and most linkers seem to treat them as essentially identical anyway. Regardless, all calls to `flushZcu` are gone now, so it's deleted -- one `flush` to rule them all! The end result of this commit and the preceding one is that LLVM and LLD fit into the pipeline much more sanely: * If we're using LLVM for the ZCU, that state is on `zcu.llvm_object` * If we're using LLD to link, then the `link.File` is a `link.Lld` * Calls to "ZCU link functions" (e.g. `updateNav`) lower to calls to the LLVM object if it's available, or otherwise to the `link.File` if it's available (neither is available under `-fno-emit-bin`) * After everything is done, linking is finalized by calling `flush` on the `link.File`; for `link.Lld` this invokes LLD, for other linkers it flushes self-hosted linker state There's one messy thing remaining, and that's how self-hosted function codegen in a ZCU works; right now, we process AIR with a call sequence something like this: * `link.doTask` * `Zcu.PerThread.linkerUpdateFunc` * `link.File.updateFunc` * `link.Elf.updateFunc` * `link.Elf.ZigObject.updateFunc` * `codegen.generateFunction` * `arch.x86_64.CodeGen.generate` So, we start in the linker, take a scenic detour through `Zcu`, go back to the linker, into its implementation, and then... right back out, into code which is generic over the linker implementation, and then dispatch on the *backend* instead! Of course, within `arch.x86_64.CodeGen`, there are some more places which switch on the `link` implementation being used. This is all pretty silly... so it shall be my next target.
2025-06-12compiler: slightly untangle LLVM from the linkersmlugg
The main goal of this commit is to make it easier to decouple codegen from the linkers by being able to do LLVM codegen without going through the `link.File`; however, this ended up being a nice refactor anyway. Previously, every linker stored an optional `llvm.Object`, which was populated when using LLVM for the ZCU *and* linking an output binary; and `Zcu` also stored an optional `llvm.Object`, which was used only when we needed LLVM for the ZCU (e.g. for `-femit-llvm-bc`) but were not emitting a binary. This situation was incredibly silly. It meant there were N+1 places the LLVM object might be instead of just 1, and it meant that every linker had to start a bunch of methods by checking for an LLVM object, and just dispatching to the corresponding method on *it* instead if it was not `null`. Instead, we now always store the LLVM object on the `Zcu` -- which makes sense, because it corresponds to the object emitted by, well, the Zig Compilation Unit! The linkers now mostly don't make reference to LLVM. `Compilation` makes sure to emit the LLVM object if necessary before calling `flush`, so it is ready for the linker. Also, all of the `link.File` methods which act on the ZCU -- like `updateNav` -- now check for the LLVM object in `link.zig` instead of in every single individual linker implementation. Notably, the change to LLVM emit improves this rather ludicrous call chain in the `-fllvm -flld` case: * Compilation.flush * link.File.flush * link.Elf.flush * link.Elf.linkWithLLD * link.Elf.flushModule * link.emitLlvmObject * Compilation.emitLlvmObject * llvm.Object.emit Replacing it with this one: * Compilation.flush * llvm.Object.emit ...although we do currently still end up in `link.Elf.linkWithLLD` to do the actual linking. The logic for invoking LLD should probably also be unified at least somewhat; I haven't done that in this commit.
2025-06-12compiler: minor refactors to ZCU linkingmlugg
* The `codegen_nav`, `codegen_func`, `codegen_type` tasks are renamed to `link_nav`, `link_func`, and `link_type`, to more accurately reflect their purpose of sending data to the *linker*. Currently, `link_func` remains responsible for codegen; this will change in an upcoming commit. * Don't go on a pointless detour through `PerThread` when linking ZCU functions/`Nav`s; so, the `linkerUpdateNav` etc logic now lives in `link.zig`. Currently, `linkerUpdateFunc` is an exception, because it has broader responsibilities including codegen, but this will be solved in an upcoming commit.
2025-06-06link: support static archives that are linker scriptsJacob Young
Note that `openLoadArchive` already has linker script support. With this change I get a failure parsing a real archive in the self hosted elf linker, rather than the previous behavior of getting an error while trying to parse a pseudo archive that is actually a load script.
2025-05-29Legalize: introduce a new pass before livenessJacob Young
Each target can opt into different sets of legalize features. By performing these transformations before liveness, instructions that become unreferenced will have up-to-date liveness information.
2025-05-18compiler: refactor `Zcu.File` and path representationmlugg
This commit makes some big changes to how we track state for Zig source files. In particular, it changes: * How `File` tracks its path on-disk * How AstGen discovers files * How file-level errors are tracked * How `builtin.zig` files and modules are created The original motivation here was to address incremental compilation bugs with the handling of files, such as #22696. To fix this, a few changes are necessary. Just like declarations may become unreferenced on an incremental update, meaning we suppress analysis errors associated with them, it is also possible for all imports of a file to be removed on an incremental update, in which case file-level errors for that file should be suppressed. As such, after AstGen, the compiler must traverse files (starting from analysis roots) and discover the set of "live files" for this update. Additionally, the compiler's previous handling of retryable file errors was not very good; the source location the error was reported as was based only on the first discovered import of that file. This source location also disappeared on future incremental updates. So, as a part of the file traversal above, we also need to figure out the source locations of imports which errors should be reported against. Another observation I made is that the "file exists in multiple modules" error was not implemented in a particularly good way (I get to say that because I wrote it!). It was subject to races, where the order in which different imports of a file were discovered affects both how errors are printed, and which module the file is arbitrarily assigned, with the latter in turn affecting which other files are considered for import. The thing I realised here is that while the AstGen worker pool is running, we cannot know for sure which module(s) a file is in; we could always discover an import later which changes the answer. So, here's how the AstGen workers have changed. We initially ensure that `zcu.import_table` contains the root files for all modules in this Zcu, even if we don't know any imports for them yet. Then, the AstGen workers do not need to be aware of modules. Instead, they simply ignore module imports, and only spin off more workers when they see a by-path import. During AstGen, we can't use module-root-relative paths, since we don't know which modules files are in; but we don't want to unnecessarily use absolute files either, because those are non-portable and can make `error.NameTooLong` more likely. As such, I have introduced a new abstraction, `Compilation.Path`. This type is a way of representing a filesystem path which has a *canonical form*. The path is represented relative to one of a few special directories: the lib directory, the global cache directory, or the local cache directory. As a fallback, we use absolute (or cwd-relative on WASI) paths. This is kind of similar to `std.Build.Cache.Path` with a pre-defined list of possible `std.Build.Cache.Directory`, but has stricter canonicalization rules based on path resolution to make sure deduplicating files works properly. A `Compilation.Path` can be trivially converted to a `std.Build.Cache.Path` from a `Compilation`, but is smaller, has a canonical form, and has a digest which will be consistent across different compiler processes with the same lib and cache directories (important when we serialize incremental compilation state in the future). `Zcu.File` and `Zcu.EmbedFile` both contain a `Compilation.Path`, which is used to access the file on-disk; module-relative sub paths are used quite rarely (`EmbedFile` doesn't even have one now for simplicity). After the AstGen workers all complete, we know that any file which might be imported is definitely in `import_table` and up-to-date. So, we perform a single-threaded graph traversal; similar to what `resolveReferences` plays for `AnalUnit`s, but for files instead. We figure out which files are alive, and which module each file is in. If a file turns out to be in multiple modules, we set a field on `Zcu` to indicate this error. If a file is in a different module to a prior update, we set a flag instructing `updateZirRefs` to invalidate all dependencies on the file. This traversal also discovers "import errors"; these are errors associated with a specific `@import`. With Zig's current design, there is only one possible error here: "import outside of module root". This must be identified during this traversal instead of during AstGen, because it depends on which module the file is in. I tried also representing "module not found" errors in this same way, but it turns out to be much more useful to report those in Sema, because of use cases like optional dependencies where a module import is behind a comptime-known build option. For simplicity, `failed_files` now just maps to `?[]u8`, since the source location is always the whole file. In fact, this allows removing `LazySrcLoc.Offset.entire_file` completely, slightly simplifying some error reporting logic. File-level errors are now directly built in the `std.zig.ErrorBundle.Wip`. If the payload is not `null`, it is the message for a retryable error (i.e. an error loading the source file), and will be reported with a "file imported here" note pointing to the import site discovered during the single-threaded file traversal. The last piece of fallout here is how `Builtin` works. Rather than constructing "builtin" modules when creating `Package.Module`s, they are now constructed on-the-fly by `Zcu`. The map `Zcu.builtin_modules` maps from digests to `*Package.Module`s. These digests are abstract hashes of the `Builtin` value; i.e. all of the options which are placed into "builtin.zig". During the file traversal, we populate `builtin_modules` as needed, so that when we see this imports in Sema, we just grab the relevant entry from this map. This eliminates a bunch of awkward state tracking during construction of the module graph. It's also now clearer exactly what options the builtin module has, since previously it inherited some options arbitrarily from the first-created module with that "builtin" module! The user-visible effects of this commit are: * retryable file errors are now consistently reported against the whole file, with a note pointing to a live import of that file * some theoretical bugs where imports are wrongly considered distinct (when the import path moves out of the cwd and then back in) are fixed * some consistency issues with how file-level errors are reported are fixed; these errors will now always be printed in the same order regardless of how the AstGen pass assigns file indices * incremental updates do not print retryable file errors differently between updates or depending on file structure/contents * incremental updates support files changing modules * incremental updates support files becoming unreferenced Resolves: #22696
2025-05-12Merge pull request #23700 from sorairolake/rename-trimsAlex Rønne Petersen
chore(std.mem): Rename `trimLeft` and `trimRight` to `trimStart` and `trimEnd`
2025-05-12Merge pull request #23835 from alexrp/freebsd-libcAlex Rønne Petersen
Support dynamically-linked FreeBSD libc when cross-compiling
2025-05-10std.Target: Remove ObjectFormat.nvptx (and associated linker code).Alex Rønne Petersen
Textual PTX is just assembly language like any other. And if we do ever add support for emitting PTX object files after reverse engineering the bytecode format, we'd be emitting ELF files like the CUDA toolchain. So there's really no need for a special ObjectFormat tag here, nor linker code that treats it as a distinct format.
2025-05-10compiler: Move vendored library support to `libs` subdirectory.Alex Rønne Petersen
2025-04-27chore(std.mem): Rename `trimLeft` and `trimRight`Shun Sakai
Rename `trimLeft` to `trimStart`, and `trimRight` to `trimEnd`. `trimLeft` and `trimRight` functions remain as deprecated aliases for these new names.
2025-04-27link: Stub out GOFF/XCOFF linker code based on LLVM.Alex Rønne Petersen
This allows emitting object files for s390x-zos (GOFF) and powerpc(64)-aix (XCOFF). Note that GOFF emission in LLVM is still being worked on upstream for LLVM 21; the resulting object files are useless right now. Also, -fstrip is required, or LLVM will SIGSEGV during DWARF emission.
2025-03-23codegen: fix packed byte-aligned relocationsJacob Young
Closes #23131
2025-03-22link: mark prelink tasks as procesed under `-fno-emit-bin`mlugg
The old logic only decremented `remaining_prelink_tasks` if `bin_file` was not `null`. This meant that on `-fno-emit-bin` builds with registered prelink tasks (e.g. C source files), we exited from `Compilation.performAllTheWorkInner` early, assuming a prelink error. Instead, when `bin_file` is `null`, we still decrement `remaining_prelink_tasks`; we just don't do any actual work. Resolves: #22682
2025-03-02link: make sure MachO closes the damn filesmlugg
Windows is a ridiculous operating system designed by toddlers, and so requires us to close all file handles in the `tmp/xxxxxxx` cache dir before renaming it into `o/xxxxxxx`. We have a hack in place to handle this for the main output file, but the MachO linker also outputs a file with debug symbols, and we weren't closing it! This led to a fuckton of CI failures when we enabled `.whole` cache mode by default for self-hosted backends. thanks jacob for figuring this out while i sat there
2025-02-25Compilation: correct when to include ubsanDavid Rubin
2025-02-25move libubsan to `lib/` and integrate it into `-fubsan-rt`David Rubin
2025-02-22Merge pull request #22659 from ifreund/linker-script-fixAndrew Kelley
link: fix ambiguous names in linker scripts
2025-02-22link.MachO: Add support for the -x flag (discard local symbols).Alex Rønne Petersen
This can also be extended to ELF later as it means roughly the same thing there. This addresses the main issue in #21721 but as I don't have a macOS machine to do further testing on, I can't confirm whether zig cc is able to pass the entire cgo test suite after this commit. It can, however, cross-compile a basic program that uses cgo to x86_64-macos-none which previously failed due to lack of -x support. Unlike previously, the resulting symbol table does not contain local symbols (such as C static functions). I believe this satisfies the related donor bounty: https://ziglang.org/news/second-donor-bounty
2025-02-17std.Target: Remove functions that just wrap component functions.Alex Rønne Petersen
Functions like isMinGW() and isGnuLibC() have a good reason to exist: They look at multiple components of the target. But functions like isWasm(), isDarwin(), isGnu(), etc only exist to save 4-8 characters. I don't think this is a good enough reason to keep them, especially given that: * It's not immediately obvious to a reader whether target.isDarwin() means the same thing as target.os.tag.isDarwin() precisely because isMinGW() and similar functions *do* look at multiple components. * It's not clear where we would draw the line. The logical conclusion before this commit would be to also wrap Arch.isX86(), Os.Tag.isSolarish(), Abi.isOpenHarmony(), etc... this obviously quickly gets out of hand. * It's nice to just have a single correct way of doing something.
2025-02-10link: simplify control flowIsaac Freund
This refactor was left out of the previous commit to make the diff less noisy and easier to review. There should be no change in behavior.
2025-02-10link: fix ambiguous names in linker scriptsIsaac Freund
Currently zig fails to build while linking the system LLVM/C++ libraries on my Chimera Linux system due to the fact that libc++.so is a linker script with the following contents: INPUT(libc++.so.1 -lc++abi -lunwind) Prior to this commit, zig would try to convert "ambiguous names" in linker scripts such as libc++.so.1 in this example into -lfoo style flags. This fails in this case due to the so version number as zig checks for exactly the .so suffix. Furthermore, I do not think that this conversion is semantically correct since converting libfoo.so to -lfoo could theoretically end up resulting in libfoo.a getting linked which seems wrong when a different file is specified in the linker script. With this patch, this attempted conversion is removed. Instead, zig always first checks if the exact file/path in the linker script exists relative to the current working directory. If the file is classified as a library (including versioned shared objects such as libfoo.so.1), zig then falls back to checking if the exact file/path in the linker script exists relative to each directory in the library search path, selecting the first match or erroring out if none is found. This behavior fixes the regression that prevents building zig while linking the system LLVM/C++ libraries on Chimera Linux.
2025-02-10std.ArrayList: popOrNull() -> pop() [v2] (#22720)Meghan Denny
2025-02-04Zcu: remove `*_loaded` fields on `File`mlugg
Instead, `source`, `tree`, and `zir` should all be optional. This is precisely what we're actually trying to model here; and `File` isn't optimized for memory consumption or serializability anyway, so it's fine to use a couple of extra bytes on actual optionals here.
2025-01-15fix merge conflicts with updating line numbersAndrew Kelley
2025-01-15type checking for synthetic functionsAndrew Kelley
2025-01-15wasm linker: improve error messages by making source locations more lazyAndrew Kelley
2025-01-15wasm linker: fix crashes when parsing compiler_rtAndrew Kelley
2025-01-15implement the prelink phase in the frontendAndrew Kelley
this strategy uses a "postponed" queue to handle codegen tasks that spawn too early. there's probably a better way.
2025-01-15wasm linker: allow undefined imports when lib name is providedAndrew Kelley
and expose object_host_name as an option for setting the lib name for object files, since the wasm linking standards don't specify a way to do it.
2025-01-15fix compilation when enabling llvmAndrew Kelley
2025-01-15compiler: add type safety for export indicesAndrew Kelley
2025-01-15rework error handling in the backendsAndrew Kelley
2025-01-15elf linker: conform to explicit error setsAndrew Kelley
2025-01-15macho linker conforms to explicit error sets, againAndrew Kelley
2025-01-15macho linker: conform to explicit error setsAndrew Kelley
Makes linker functions have small error sets, required to report diagnostics properly rather than having a massive error set that has a lot of codes. Other linker implementations are not ported yet. Also the branch is not passing semantic analysis yet.
2025-01-15wasm linker: aggressive DODificationAndrew Kelley
The goals of this branch are to: * compile faster when using the wasm linker and backend * enable saving compiler state by directly copying in-memory linker state to disk. * more efficient compiler memory utilization * introduce integer type safety to wasm linker code * generate better WebAssembly code * fully participate in incremental compilation * do as much work as possible outside of flush(), while continuing to do linker garbage collection. * avoid unnecessary heap allocations * avoid unnecessary indirect function calls In order to accomplish this goals, this removes the ZigObject abstraction, as well as Symbol and Atom. These abstractions resulted in overly generic code, doing unnecessary work, and needless complications that simply go away by creating a better in-memory data model and emitting more things lazily. For example, this makes wasm codegen emit MIR which is then lowered to wasm code during linking, with optimal function indexes etc, or relocations are emitted if outputting an object. Previously, this would always emit relocations, which are fully unnecessary when emitting an executable, and required all function calls to use the maximum size LEB encoding. This branch introduces the concept of the "prelink" phase which occurs after all object files have been parsed, but before any Zcu updates are sent to the linker. This allows the linker to fully parse all objects into a compact memory model, which is guaranteed to be complete when Zcu code is generated. This commit is not a complete implementation of all these goals; it is not even passing semantic analysis.
2025-01-05link: new incremental line number update APImlugg
2024-12-24compiler: analyze type and value of global declaration separatelymlugg
This commit separates semantic analysis of the annotated type vs value of a global declaration, therefore allowing recursive and mutually recursive values to be declared. Every `Nav` which undergoes analysis now has *two* corresponding `AnalUnit`s: `.{ .nav_val = n }` and `.{ .nav_ty = n }`. The `nav_val` unit is responsible for *fully resolving* the `Nav`: determining its value, linksection, addrspace, etc. The `nav_ty` unit, on the other hand, resolves only the information necessary to construct a *pointer* to the `Nav`: its type, addrspace, etc. (It does also analyze its linksection, but that could be moved to `nav_val` I think; it doesn't make any difference). Analyzing a `nav_ty` for a declaration with no type annotation will just mark a dependency on the `nav_val`, analyze it, and finish. Conversely, analyzing a `nav_val` for a declaration *with* a type annotation will first mark a dependency on the `nav_ty` and analyze it, using this as the result type when evaluating the value body. The `nav_val` and `nav_ty` units always have references to one another: so, if a `Nav`'s type is referenced, its value implicitly is too, and vice versa. However, these dependencies are trivial, so, to save memory, are only known implicitly by logic in `resolveReferences`. In general, analyzing ZIR `decl_val` will only analyze `nav_ty` of the corresponding `Nav`. There are two exceptions to this. If the declaration is an `extern` declaration, then we immediately ensure the `Nav` value is resolved (which doesn't actually require any more analysis, since such a declaration has no value body anyway). Additionally, if the resolved type has type tag `.@"fn"`, we again immediately resolve the `Nav` value. The latter restriction is in place for two reasons: * Functions are special, in that their externs are allowed to trivially alias; i.e. with a declaration `extern fn foo(...)`, you can write `const bar = foo;`. This is not allowed for non-function externs, and it means that function types are the only place where it is possible for a declaration `Nav` to have a `.@"extern"` value without actually being declared `extern`. We need to identify this situation immediately so that the `decl_ref` can create a pointer to the *real* extern `Nav`, not this alias. * In certain situations, such as taking a pointer to a `Nav`, Sema needs to queue analysis of a runtime function if the value is a function. To do this, the function value needs to be known, so we need to resolve the value immediately upon `&foo` where `foo` is a function. This restriction is simple to codify into the eventual language specification, and doesn't limit the utility of this feature in practice. A consequence of this commit is that codegen and linking logic needs to be more careful when looking at `Nav`s. In general: * When `updateNav` or `updateFunc` is called, it is safe to assume that the `Nav` being updated (the owner `Nav` for `updateFunc`) is fully resolved. * Any `Nav` whose value is/will be an `@"extern"` or a function is fully resolved; see `Nav.getExtern` for a helper for a common case here. * Any other `Nav` may only have its type resolved. This didn't seem to be too tricky to satisfy in any of the existing codegen/linker backends. Resolves: #131
2024-12-20lldb: add pretty printer for intern pool indicesJacob Young
2024-12-10std.Build.Cache.hit: more discipline in error handlingAndrew Kelley
Previous commits 2b0929929d67e222ca6a9523a3a594ed456c4a51 4ea2f441df36cec61e1017f4d795d4037326c98c had this text: > There are no dir components, so you would think that this was > unreachable, however we have observed on macOS two processes racing to > do openat() with O_CREAT manifest in ENOENT. This appears to have been a misunderstanding based on the issue report #12138 and corresponding PR #12139 in which the steps to reproduce removed the cache directory in a loop which also executed detached Zig compiler processes. There is no evidence for the macOS kernel bug however the ENOENT is easily explained by the removal of the cache directory. This commit reverts those commits, ultimately reporting the ENOENT as an error rather than repeating the create file operation. However this commit also adds an explicit error set to `std.Build.Cache.hit` as well as changing the `failed_file_index` to a proper diagnostic field that fully communicates what failed, leading to more informative error messages on failure to check the cache. The equivalent failure when occuring for AstGen performs a fatal process kill, reasoning being that the compiler has an invariant of the cache directory not being yanked out from underneath it while executing. This could be made a more granular error in the future but I suspect such thing is not valuable to pursue. Related to #18340 but does not solve it.
2024-11-26diversify "unable to spawn" failure messagesAndrew Kelley
to help understand where a spurious failure is occurring
2024-10-30link.File.Wasm: parse inputs in compilation pipelineAndrew Kelley
Primarily, this moves linker input parsing from flush() into the linker task queue, which is executed simultaneously with the frontend. I also made it avoid redundantly opening the same archive file N times for each object file inside. Furthermore, hard code fixed buffer stream rather than using a generic stream type. Finally, I fixed the error handling of the Wasm.Archive.parse function. Please pay attention to this pattern of returning a struct rather than accepting a mutable struct as an argument. This ensures function-level atomicity and makes resource management straightforward. Deletes the file and path fields from Archive and Object. Removed a well-meaning but ultimately misguided suggestion about how to think about ZigObject since thinking about it that way has led to problematic anti-DOD patterns.
2024-10-31link: Fix archive format selection for some OSs.Alex Rønne Petersen
* AIX has its own bespoke format. * Handle all Apple platforms. * FreeBSD and OpenBSD both use the GNU format in LLVM. * Windows has since been switched to the COFF format by default in LLVM.