Previously, when multiple modules had builtin modules with identical
sources, two distinct `Module`s and `File`s were created pointing at the
same file path. This led to a bug later in the frontend. These modules
are now deduplicated with a simple hashmap on the builtin source.
Instead of making its own inside create. 10 out of 10 calls to create()
had already an arena in scope, so this commit means that 10 instances of
Compilation now reuse an existing arena with the same lifetime rather
than creating a redundant one.
In other words, this very slightly optimizes initialization of the
frontend in terms of memory allocation.
Finish the work started in 4c4fb839972f66f55aa44fc0aca5f80b0608c731.
Now the compiler compiles again.
Wire up dependency tree fetching code in the CLI for `zig build`.
Everything is hooked up except for `createDependenciesModule` is not yet
implemented.
This makes progress be exposed to the top-level caller of update().
I tossed in a bonus change: when the `zig build` subcommand sees exit
code 2, it omits the "following command failed" line, and the build
runner uses exit code 2 when there are compile errors. This tidies up
the output on build failure by a little bit.
Introduces std.zig.ErrorBundle which is a trivially serializeable set
of compilation errors. This is in the standard library so that both
the compiler and the build runner can use it. The idea is they will
use it to communicate compilation errors over a binary protocol.
The binary encoding of ErrorBundle is a bit problematic - I got a little
too aggressive with compaction. I need to change it in a follow-up
commit to use some indirection in the error message list, otherwise
iteration is too unergonomic. In fact it's so problematic right now that
the logic getAllErrorsAlloc() actually fails to produce a viable
ErrorBundle because it puts SourceLocation data in between the root
level ErrorMessage data.
This commit has a simplification - redundant logic for rendering AST
errors to stderr has been removed in favor of moving the logic for
lowering AST errors into AstGen. So even if we get parse errors, the
errors will get lowered into ZIR before being reported. I believe this
will be useful when working on --autofix. Either way, some redundant
brittle logic was happily deleted.
In Compilation, updateSubCompilation() is improved to properly perform
error reporting when a sub-compilation object fails. It no longer dumps
directly to stderr; instead it populates an ErrorBundle object, which
gets added to the parent one during getAllErrorsAlloc().
In package fetching code, instead of dumping directly to stderr, it now
populates an ErrorBundle object, and gets properly reported at the CLI
layer of abstraction.
The two CacheMode values are `whole` and `incremental`.
`incremental` is what we had before; `whole` is new.
Whole cache mode uses everything as inputs to the cache hash;
and when a hit occurs it skips everything including linking.
This is ideal for when source files change rarely and for backends that
do not have good incremental compilation support, for example
compiler-rt or libc compiled with LLVM with optimizations on.
This is the main motivation for the additional mode, so that we can have
LLVM-optimized compiler-rt/libc builds, without waiting for the LLVM
backend every single time Zig is invoked.
Incremental cache mode hashes only the input file path and a few target
options, intentionally relying on collisions to locate already-existing
build artifacts which can then be incrementally updated.
The bespoke logic for caching stage1 backend build artifacts
is removed since we now have a global caching mechanism for
when we want to cache the entire compilation, *including* linking.
Previously we had to get "creative" with libs.txt and a special
byte in the hash id to communicate flags, so that when the cached
artifacts were re-linked, we had this information from stage1
even though we didn't actually run it. Now that `CacheMode.whole`
includes linking, this extra information does not need to be
preserved for cache hits. So although this changeset introduces
complexity, it also removes complexity.
The main trickiness here comes from the inherent differences between the
two modes: `incremental` wants a directory immediately to operate on,
while `whole` doesn't know the output directory until the compilation is
complete. This commit deals with this problem mostly inside `update()`,
where, on a cache miss, it replaces `zig_cache_artifact_directory` with a
temporary directory, and then renames it into place once the compilation is
complete.
Items remaining before this branch can be merged:
* [ ] make sure these things make it into the cache manifest:
- @import files
- @embedFile files
- we already add dep files from c but make sure the main .c files make
it in there too, not just the included files
* [ ] double check that the emit paths of other things besides the binary
are working correctly.
* [ ] test `-fno-emit-bin` + `-fstage1`
* [ ] test `-femit-bin=foo` + `-fstage1`
* [ ] implib emit directory copies bin_file_emit directory in create() and needs
to be adjusted to be overridden as well.
* [ ] make sure emit-h is handled correctly in the cache hash
* [ ] Cache: detect duplicate files added to the manifest
Some preliminary performance measurements of wall clock time and
peak RSS used:
stage1 behavior (1077 tests), llvm backend, release build:
* cold global cache: 4.6s, 1.1 GiB
* warm global cache: 3.4s, 980 MiB
stage2 master branch behavior (575 tests), llvm backend, release build:
* cold global cache: 0.62s, 191 MiB
* warm global cache: 0.40s, 128 MiB
stage2 this branch behavior (575 tests), llvm backend, release build:
* cold global cache: 0.62s, 179 MiB
* warm global cache: 0.27s, 90 MiB
* There is now a main_pkg in addition to root_pkg. They are usually the
same. When using `zig test`, main_pkg is the user's source file and
root_pkg has the test runner.
* scanDecl no longer looks for test decls outside the package being
tested. honoring `--test-filter` is still TODO.
* test runner main function has a void return value rather than
`anyerror!void`
* Sema is improved to generate better AIR for for loops on slices.
* Sema: fix incorrect capacity calculation in zirBoolBr
* Sema: add compile errors for trying to use slice fields as an lvalue.
* Sema: fix type coercion for error unions
* Sema: fix analyzeVarRef generating garbage AIR
* C codegen: fix renderValue for error unions with 0 bit payload
* C codegen: implement function pointer calls
* CLI: fix usage text
Adds 4 new AIR instructions:
* slice_len, slice_ptr: to get the ptr and len fields of a slice.
* slice_elem_val, ptr_slice_elem_val: to get the element value of
a slice, and a pointer to a slice.
AstGen gains a new functionality:
* One of the unused flags of struct decls is now used to indicate
structs that are known to have non-zero size based on the AST alone.
closes#9034
These options were listed under the
"Debug Options (Zig Compiler Development)" heading. Anything in this
section should be considered unstable and can be modified at any time
at any developer's discretion.
Previously Zig would need to recompile runtime libs if you changed the
values of --strip or -O. Now, unless the `debug_compiler_runtime_libs`
flag is set (which is currently not exposed to the CLI), Zig will always
choose ReleaseFast or ReleaseSmall for compiler runtime libraries.
When the main application chooses ReleaseFast or ReleaseSmall, that
value is propagated to compiler runtime libraries. Otherwise a decision
is made based on the target, which is currently ReleaseSmall for
freestanding WebAssembly and ReleaseFast for everything else.
Ultimately the purpose of this commit is to have Debug and ReleaseSafe
builds of applications still get optimized builds of, e.g. libcxx and
libunwind, as well as to spend less time unnecessarily rebuilding compiler
runtime libraries.
* rename is_compiler_rt_or_libc to skip_linker_dependencies
and set it to `true` for all sub-Compilations. I believe
this resolves the deadlock we were experiencing on Drone
CI and on some users' computers. I will remove the CI workaround in
a follow-up commit.
* enabling TSAN automatically causes the Compilation to link against
libc++ even if not requested, because TSAN depends on libc++.
* add -fno-rtti flags where appropriate when building TSAN objects.
Thanks Firefox317 for pointing this out.
* TSAN support: resolve all the undefined symbols. We are still seeing
a dependency on __gcc_personality_v0 but will resolve this one in a
follow-up commit.
* static libs do not try to build libc++ or libc++abi.
