test: verify linker ASSERT catches missing export_startup#944
Closed
test: verify linker ASSERT catches missing export_startup#944
Conversation
The firmware executable's root module is now the user's application
source, not microzig's start.zig shim. This aligns microzig with the
standard Zig build idiom: `@import("root")` from any module resolves to
user code, `pub const panic` / `pub const std_options` live where Zig
expects to find them, and tooling that assumes root-is-the-app now
works naturally.
Core changes:
- microzig.zig reads `microzig_options` via `@import("root")` instead of
the injected `app` module, and drops the `pub const app` alias.
- utilities.install_startup / core/src/start.zig are replaced by a
single user-facing primitive, `microzig.export_startup()`, which the
application opts into from a comptime block. It emits the CPU
startup symbols and the `microzig_main` wrapper that the CPU `_start`
calls once `.data`/`.bss` are initialized.
- Startup logic (HAL init / root init / error-returning main / panic
wrapping) moves out of start.zig into microzig_main, with identical
semantics.
- A new `microzig.std_options()` helper returns a `std.Options` with
microzig's freestanding-safe defaults (the critical one being a no-op
`logFn` that replaces stdlib's stderr-writing default, which fails to
link on freestanding). The accompanying `StdOptions` struct documents
which std.Options fields are exposed and which are intentionally
excluded as hosted-only.
- The log-related fields (`log_level`, `log_scope_levels`, `logFn`) are
removed from `microzig.Options`; they now live exclusively in
`std.Options` via the helper.
Build system:
- `add_firmware` sets `exe.root_module = app_mod` directly. The
separate start.zig root module and the "app"-import plumbing on
`core_mod` / `cpu_mod` / `chip_mod` / `hal_mod` / `board_mod` are
all gone.
Example boilerplate (now two re-exports and one comptime line):
pub const panic = microzig.panic;
pub const std_options = microzig.std_options(.{});
comptime {
_ = microzig.export_startup();
}
All 131 example main.zig files have been migrated. Examples that
previously declared `pub const microzig_options` with log-related
fields have had those fields moved into `microzig.std_options(...)`,
with any remaining microzig-specific fields (interrupts, hal, cpu,
etc.) kept in a trimmed `pub const microzig_options`.
The website getting-started snippet is updated to match.
This commit only performs the structural move. It is NOT expected to
build against 0.15.x or current 0.16.x compilers as-is; the separate
0.16 migration work comes next.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Contributor
Author
|
Test complete. The linker script ASSERT successfully catches missing export_startup() with a clear error message. |
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Temporary PR to verify that the linker script
ASSERT(DEFINED(microzig_main), ...)produces a clear linker error when a user forgets to callmicrozig.export_startup(). Will be closed immediately after verification.