This commit changes how `std.io.poll` is implemented on Windows. The new
implementation unfortunately incurs a little extra system call overhead,
but fixes several bugs in the old implementation:
* The `lpNumberOfBytesRead` parameter of `ReadFile` was used with
overlapped I/O. This is explicitly disallowed by the documentation, as
the value written to this pointer is "potentially erroneous"; instead,
`GetOverlappedResult` must always be used, even if the operation
immediately returns. Documentation states that `lpNumberOfBytesRead`
cannot be passed as null on Windows 7, so for compatibility, the
parameter is passed as a pointer to a dummy global.
* If the initial `ReadFile` returned data, and the next read returned
`BROKEN_PIPE`, the received data was silently ignored in the sense
that `pollWindows` did not `return`, instead waiting for data to come
in on another file (or for all files to close).
* The asynchronous `ReadFile` calls which were left pending between
calls to `pollWindows` pointed to a potentially unstable buffer, since
the user of `poll` may use part of the `LinearFifo` API which rotate
its ring buffer. This race condition was causing CI failures in some
uses of the compiler server protocol.
These issues are all resolved. Now, `pollWindows` will queue an initial
read to a small (128-byte) stable buffer per file. When this read is
completed, reads directly into the FIFO's writable slice are performed
until one is left pending, at which point that read is cancelled (with a
check to see if it was completed between the `ReadFile` and `CancelIo`
calls) and the next read into the small stable buffer is queued. These
small buffer reads are the ones left pending between `pollWindows`
calls, avoiding the race condition described above.
Related: #21565
Throw another target in there just to spice things up a little!
Running the incremental cases with the C backend is pretty slow due to
the need to recompile the whole output from scratch on every update; for
this reason, we probably don't want to keep many of these targeting CBE
long-term. However, for now, while we have relatively few tests and
things are still changing quite a lot, it's better to have this little
bit of extra test coverage.
If no external executor is available for a successful binary, its
execution is silently skipped. This allows the CI to test, to the
fullest extent possible, incremental cross-compilation to targets whose
binaries can't be executed on the host.
This is contained in the `test` step, so is tested by CI.
This commit also includes some enhancements to the `incr-check` tool to
make this work correctly.
* Adds new cpu architectures propeller1 and propeller2.
These cpu architectures allow targeting the Parallax Propeller 1 and Propeller 2, which are both very special microcontrollers with 512 registers and 8 cpu cores.
Resolves#21559
* Adds std.elf.EM.PROPELLER and std.elf.EM.PROPELLER2
* Fixes missing switch prongs in src/codegen/llvm.zig
* Fixes order in std.Target.Arch
---------
Co-authored-by: Felix "xq" Queißner <git@random-projects.net>
On s390x-linux, fstat() does not have nanosecond precision, but fstatat() does.
As a result, comparing Stat structs returned from these syscalls is doomed to
fail.
Until we actually figure out a version range for this, we shouldn't classify
this as using semver. Doing so results in a panic when trying to access the
version range since it's not in fact a semver value.
Only targets for which we don't source CPU models/features from LLVM should use
the fallback prong in this switch. Also make it exhaustive to catch similar
mistakes in the future.
At bare minimum, the compiler expects std.Target.<arch>.cpu.generic to work for
any given architecture when generating the builtin module. So rather than try to
hack that into working when the affected modules are omitted, just actually keep
them.
This affected lanai and xcore.
* Added error message 'ProcessNotFound' for reading and writing in a Linux
process.
This error occurs if the process to be read from or written to no longer exists.
Fixes#19875
* Added error message "ProcessNotFound" for error forwarding.
* Add error messgae for forwarding.
* Added message for forwarding.
* Error set completed.
* Fixed format error.
* Changed comments to doc comments.
