Turns out that even modern Debian aarch64 glibc libc_nonshared.a has
references to _init, meaning that the previous commit caused a
regression when trying to build any -lc executable on that target.
This commit backs out the changes to LibCInstallation.
There is still a fork in the road coming up when the self-hosted ELF
linker becomes load bearing on that target.
crti.o/crtn.o is a legacy strategy for calling constructor functions
upon object loading that has been superseded by the
init_array/fini_array mechanism.
Zig code depends on neither, since the language intentionally has no way
to initialize data at runtime, but alas the Zig linker still must
support this feature since popular languages depend on it.
Anyway, the way it works is that crti.o has the machine code prelude of
two functions called _init and _fini, each in their own section with the
respective name. crtn.o has the machine code instructions comprising the
exitlude for each function. In between, objects use the .init and .fini
link section to populate the function body.
This function is then expected to be called upon object initialization
and deinitialization.
This mechanism is depended on by libc, for example musl and glibc, but
only for older ISAs. By the time the libcs gained support for newer
ISAs, they had moved on to the init_array/fini_array mechanism instead.
For the Zig linker, we are trying to move the linker towards
order-independent objects which is incompatible with the legacy
crti/crtn mechanism.
Therefore, this commit drops support entirely for crti/crtn mechanism,
which is necessary since the other commits in this branch make it
nondeterministic in which order the libc objects and the other link
inputs are sent to the linker.
The linker is still expected to produce a deterministic output, however,
by ignoring object input order for the purposes of symbol resolution.
The original motivation here was to fix regressions caused by #22414.
However, while working on this, I ended up discussing a language
simplification with Andrew, which changes things a little from how they
worked before #22414.
The main user-facing change here is that any reference to a prior
function parameter, even if potentially comptime-known at the usage
site or even not analyzed, now makes a function generic. This applies
even if the parameter being referenced is not a `comptime` parameter,
since it could still be populated when performing an inline call. This
is a breaking language change.
The detection of this is done in AstGen; when evaluating a parameter
type or return type, we track whether it referenced any prior parameter,
and if so, we mark this type as being "generic" in ZIR. This will cause
Sema to not evaluate it until the time of instantiation or inline call.
A lovely consequence of this from an implementation perspective is that
it eliminates the need for most of the "generic poison" system. In
particular, `error.GenericPoison` is now completely unnecessary, because
we identify generic expressions earlier in the pipeline; this simplifies
the compiler and avoids redundant work. This also entirely eliminates
the concept of the "generic poison value". The only remnant of this
system is the "generic poison type" (`Type.generic_poison` and
`InternPool.Index.generic_poison_type`). This type is used in two
places:
* During semantic analysis, to represent an unknown result type.
* When storing generic function types, to represent a generic parameter/return type.
It's possible that these use cases should instead use `.none`, but I
leave that investigation to a future adventurer.
One last thing. Prior to #22414, inline calls were a little inefficient,
because they re-evaluated even non-generic parameter types whenever they
were called. Changing this behavior is what ultimately led to #22538.
Well, because the new logic will mark a type expression as generic if
there is any change its resolved type could differ in an inline call,
this redundant work is unnecessary! So, this is another way in which the
new design reduces redundant work and complexity.
Resolves: #22494Resolves: #22532Resolves: #22538
`std.Build.Step.Run` makes the very reasonable assumption that
`error.InvalidExe` will be reported on `spawn` if it will happen.
However, this property does not currently hold on POSIX targets. This
is, through a slightly convoluted series of events, partially
responsible for the sporadic `BrokenPipe` errors we've been seeing more
and more in CI runs.
Making `spawn` wait for the child to exec in the POSIX path introduces
a block of up to 400us. So, instead of doing that, we add a new API for
this particular case: `waitForSpawn`. This function is a nop on Windows,
but on POSIX it blocks until the child successfully (or otherwise) calls
`execvpe`, and reports the error if necessary. `std.Build.Step.Run`
calls this function, so that it can get `error.InvalidExe` when it wants
it.
I'm not convinced that this API is optimal. However, I think this entire
API needs to be either heavily refactored or straight-up redesigned
(related: #22504), so I'm not too worried about hitting the perfect API:
I'd rather just fix this bug for now, and figure out the long-term goal
a bit later.
The previous logic here was trying to assume that custom test runners
never used `std.zig.Server` to communicate with the build runner;
however, it was flawed, because modifying the `test_runner` field on
`Step.Compile` would not update this flag. That might have been
intentional (allowing a way for the user to specify a custom test runner
which *does* use the compiler server protocol), but if so, it was a
flawed API, since it was too easy to update one field without updating
the other.
Instead, bundle these two pieces of state into a new type
`std.Build.Step.Compile.TestRunner`. When passing a custom test runner,
you are now *provided* to specify whether it is a "simple" runner, or
whether it uses the compiler server protocol.
This is a breaking change, but is unlikely to affect many people, since
custom test runners are seldom used in the wild.
Note: This mostly matches resinator v0.1.0 rather than the latest master version, since the latest master version focuses on adding support for .res -> .obj conversion which is not necessary for the future planned relationship of zig and resinator (resinator will likely be moved out of the compiler and into the build system, a la translate-c).
So, ultimately the changes here consist mostly of bug fixes for obscure edge cases.
This PR adds support for handling ZIP64 format in local file headers,
when a zip file contains entries where the compressed or uncompressed
size fields are set to 0xFFFFFFFF, and the extra field contains ZIP64
extended information tag (0x0001)
The code now:
Reads the actual sizes from the ZIP64 extra field data
Validates these sizes against the entry's compressed and uncompressed sizes
Zip file format spec.: https://pkware.cachefly.net/webdocs/casestudies/APPNOTE.TXT
This change allows proper extraction of ZIP files that use ZIP64 format in their
local file headers.
Fixes: #22329
For representing struct field default values and array/pointer type
sentinel values, we use `*const anyopaque`, since there is no way for
`std.builtin.Type.StructField` etc to refer back to its `type` field.
However, when introspecting a type, this is quite awkward due to the
pointer casts necessary.
As such, this commit renames the `sentinel` fields to `sentinel_ptr`,
and the `default_value` field to `default_value_ptr`, and introduces
helper methods `sentinel()` and `defaultValue()` to load the values.
These methods are marked as `inline` because their return value, which
is always comptime-known, is very often required at comptime by use
sites, so this avoids having to annotate such calls with `comptime`.
This is a breaking change, although note that 0.14.0 is already a
breaking release for all users of `std.builtin.Type` due to the union
fields being renamed.
This was done by regex substitution with `sed`. I then manually went
over the entire diff and fixed any incorrect changes.
This diff also changes a lot of `callconv(.C)` to `callconv(.c)`, since
my regex happened to also trigger here. I opted to leave these changes
in, since they *are* a correct migration, even if they're not the one I
was trying to do!
This matches established naming conventions. Now is an opportune time to
make this change, since we're already performing breaking changes to
`std.builtin.Type`.
