| author |  Matthew Lugg <mlugg@mlugg.co.uk> 2025-11-15 09:45:22+00:00 |
| committer | Matthew Lugg <mlugg@mlugg.co.uk> 2025-11-15 09:49:02+00:00 |
| log | cd8fdd252d9ffd5bfb772cef49e4c79041872d38 |
| tree | 35e9647d4129edf2d4e5caf0b8233727d58765ab |
| parent | bc78d8efdb90c77670c30474071942f093a2427f |
| signature |  Commit is signed but in an unrecognized format. |
build.zig: use `Step.UpdateSourceFiles` for `zig1.wasm`
We were already using this for `stage1/zig.h`, but `stage1/zig1.wasm`
was being modified directly by the `wasm-opt` command. That's a bad idea
because it forces the build system to assume that `wasm-opt` has side
effects, so it is re-run every time you run `zig build update-zig1`,
i.e. it does not interact with the cache system correctly. It is much
better to create non-side-effecting `Run` steps (using `addOutput*Arg`)
where possible so that the build system has a more correct understanding
of the step graph.1 files changed, 5 insertions(+), 5 deletions(-)
build.zig+5-5
| ... | ... | @@ -678,14 +678,14 @@ fn addWasiUpdateStep(b: *std.Build, version: [:0]const u8) !void { |
| 678 | 678 | }); |
| 679 | 679 | run_opt.addArtifactArg(exe); |
| 680 | 680 | run_opt.addArg("-o"); |
| 681 | run_opt.addFileArg(b.path("stage1/zig1.wasm")); | |
| 681 | const optimized_wasm = run_opt.addOutputFileArg("zig1.wasm"); | |
| 682 | 682 | |
| 683 | const copy_zig_h = b.addUpdateSourceFiles(); | |
| 684 | copy_zig_h.addCopyFileToSource(b.path("lib/zig.h"), "stage1/zig.h"); | |
| 683 | const update_zig1 = b.addUpdateSourceFiles(); | |
| 684 | update_zig1.addCopyFileToSource(optimized_wasm, "stage1/zig1.wasm"); | |
| 685 | update_zig1.addCopyFileToSource(b.path("lib/zig.h"), "stage1/zig.h"); | |
| 685 | 686 | |
| 686 | 687 | const update_zig1_step = b.step("update-zig1", "Update stage1/zig1.wasm"); |
| 687 | update_zig1_step.dependOn(&run_opt.step); | |
| 688 | update_zig1_step.dependOn(©_zig_h.step); | |
| 688 | update_zig1_step.dependOn(&update_zig1.step); | |
| 689 | 689 | } |
| 690 | 690 | |
| 691 | 691 | const AddCompilerModOptions = struct { |