Previously, the `test-stack-traces` step was essentially just testing
error traces, and even there we didn't have much coverage. This commit
solves that by splitting the "stack trace" tests into two separate
harnesses: the "stack trace" tests are for actual stack traces (i.e.
involving stack unwinding), while the "error trace" tests are
specifically for error return traces.
The "stack trace" tests will test different configurations of:
* `-lc`
* `-fPIE`
* `-fomit-frame-pointer`
* `-fllvm`
* unwind tables (currently disabled)
* strip debug info (currently disabled)
The main goal there is to test *stack unwinding* under different
conditions. Meanwhile, the "error trace" tests will test different
configurations of `-O` and `-fllvm`; the main goal here, aside from
checking that error traces themselves do not miscompile, is to check
whether debug info is still working even in optimized builds. Of course,
aggressive optimizations *can* thwart debug info no matter what, so as
before, there is a way to disable cases for specific targets / optimize
modes.
The program which converts stack traces into a more validatable format
by removing things like addresses (previously `check-stack-trace.zig`,
now `convert-stack-trace.zig`) has been rewritten and simplified. Also,
thanks to various fixes in this branch, several workarounds have become
unnecessary: for instance, we don't need to ignore the function name
printed in stack traces in release modes, because `std.debug.Dwarf` now
uses the correct DIE for inlined functions!
Neither `test-stack-traces` nor `test-error-traces` does general foreign
architecture testing, because it seems that (at least for now) external
executors often aren't particularly good at handling stack tracing
correctly (looking at you, Wine). Generally, they just test the native
target (this matches the old behavior of `test-stack-traces`). However,
there is one exception: when on an x86_64 or aarch64 host, we will also
test the 32-bit version (x86 or arm) if the OS supports it, because such
executables can be trivially tested without an external executor.
Oh, also, I wrote a bunch of stack trace tests. Previously there was,
erm, *one* test in `test-stack-traces` which wasn't for error traces.
Now there are a good few!
Because -fno-llvm is now the default on x86_64-linux, this target was
exactly equivalent to one specified earlier in the matrix. This was
probably just missed when doing the work to enable the self-hosted
backend by default for x86_64.
If the compiler happens to pick `ret = r0`, then this will assemble to
`ag r0, 0` which is obviously not what we want. Using `a` instead of `r` will
ensure that we get an appropriate address register, i.e. `r1` through `r15`.
Re-enable pie_linux for s390x-linux which was disabled in
ed7ff0b693037078f451a7c6c1124611060f4892.
Disabled due to no active maintainer (feel free to fix the failures and
then re-enable at any time). The failures occur due to backend
miscompilation of different AIR from the frontend.
Disabled due to no active maintainer (feel free to fix the failures and
then re-enable at any time). The failures occur due to changing AIR from
the frontend, and backend being incomplete.
C translation is in the process of switching to be aro-based
(see #24497)
That codebase will need to gain some kind of helper for translating C
code that uses runtime vector indexing.
This clarifies that it is legal to return an invalid pointer from a
function, provided that such pointer is not dereferenced.
This matches current status quo of the language. Any change to this
should be a proposal that argues for different semantics.
It is also legal in C to return a pointer to a local. The C backend
lowers such thing directly, so the corresponding warning in C must be
disabled (`-Wno-return-stack-address`).
Adds `addFileContentArg` and `addPrefixedFileContentArg` to pass the content
of a file with a lazy path as an argument to a `std.Build.Step.Run`.
This enables replicating shell `$()` / cmake `execute_process` with `OUTPUT_VARIABLE`
as an input to another `execute_process` in conjuction with `captureStdOut`/`captureStdErr`.
To also be able to replicate `$()` automatically trimming trailing newlines and cmake
`OUTPUT_STRIP_TRAILING_WHITESPACE`, this patch adds an `options` arg to those functions
which allows specifying the desired handling of surrounding whitespace.
The `options` arg also allows to specify a custom `basename` for the output. e.g.
to add a file extension (concrete use case: Zig `@import()` requires files to have a
`.zig`/`.zon` extension to recognize them as valid source files).
The data structure was originally added in
41e1cd185b82a518c58c92544c45f0348c03ef74 and then removed in
50a336fff899ebd8a687c453ec6beb18a5a9baf9, but brought back in
711bf55eaa643c3d05640bebbf3e4315477b8ed8 for Decl in the compiler
frontend, and then the last reference to it was eliminated in
548a087fafeda5b07d2237d5137906b8d07da699 which removed Decl in favor of
Nav and Cau.
