SG-0

dsl/gunbc/compiler.dag

@@ -245,42 +245,35 @@ data test_package: NonEmptyStr = "v2-compiler-tests"
 // shrinks one lane at a time. The SG program (SG-0..SG-7) sequences
 // that dissolution. Each lane's PR ports a group of .rs files to
 // .dag authority AND removes those .rs files as authority in the
-// same PR — deleted, generated, or reduced to a narrow host shim
-// that carries a generated header. No dual-authority period.
+// same PR — deleted, generated, or reduced to a narrow host shim.
 //
-// This section is the STRUCTURAL authority for the census: the
-// directories that count against the inventory, and the marker that
-// separates generated files from hand-authored ones. The ENFORCED
-// authority — the concrete list of hand-authored .rs paths that
-// must only shrink over time — lives with the ratchet test at
-// src/v3/compiler/tests/integration/sg0_census_test.rs. The two
-// agree today by discipline; when the v3 pipeline is self-hosting
-// enough, the test's constant can be derived from this file.
-
-// Directories the census walks for .rs files. The walk is recursive
-// within each root; nested build artifacts (target/) are skipped by
-// the walker. One root today (`src/v3/compiler`) is enough to reach
-// every v3-compiler .rs file on disk — the crate sources, bin
-// targets, the emit subtree, the integration test tree, and the
-// crate's `build.rs`. Additional census roots land here if v3
-// ever grows Rust sources outside this crate.
-type V3CensusRoot {
-  path: FilePath
-}
-
-data v3_census_roots: List<V3CensusRoot> = [
-  { path: "src/v3/compiler" }
-]
-
-// First non-blank line prefix on every generated .rs file. Every
-// regen driver (src/v3/compiler/src/bin/regen_*.rs and the crate's
-// build.rs) prepends a header beginning with this string; the
-// census classifies any file whose first non-blank line begins with
-// it as generated-by-construction and drops it from the hand-
-// authored count. Hand-editing a generated file is still forbidden
-// by feedback_no_generated_code_on_disk — this marker is the
-// discrimination protocol, not a permission.
-data v3_generated_marker_prefix: NonEmptyStr = "// AUTO-GENERATED"
+// **What "narrow host shim" means.** A retired-to-shim .rs file's
+// ONLY hand-authored content is (a) `use` imports, (b) a `#[path]`
+// or `include!` directive pulling in generated code, or (c) `pub
+// use` re-exports that surface generated symbols under the original
+// module path. Any function body, match arm, or control-flow
+// statement keeps the file counted as hand-authored. The shim rule
+// is structural — a lens will eventually check it — but today it
+// is enforced by review.
+//
+// **No dual-authority in merged/main.** By the time an SG PR lands,
+// the old .rs is gone as authority. In-PR intermediate commits may
+// temporarily hold both old and new authorities while parity is
+// being established; the rule bites at merge time, not at every
+// commit.
+//
+// **Where the authority lives today.** SG-0 is a Rust-side ratchet:
+// `src/v3/compiler/build.rs` declares the producer-owned manifest
+// `REGEN_OUTPUTS` (the set of .rs files every codegen authority is
+// allowed to write under src/v3/compiler); `src/v3/compiler/tests/
+// integration/sg0_census_test.rs` reads that manifest to partition
+// generated vs hand-authored, and ratchets the hand-authored set
+// down. No structural data lives in this file yet — declaring the
+// census roots or generated marker here would be parallel-
+// representation debt (`feedback_parallel_representation_debt`)
+// because the test would not consume it. When v3 self-hosts enough
+// to compile this file (SG-6 cutover), the manifest migrates here
+// as first-class `.dag` data and `build.rs` is retired as authority.
 
 // ── Command derivation ──────────────────────────────────────────────
 // Every builder takes a resolved cargo/grep/diff/cp/rm path instead of

src/v3/compiler/build.rs

@@ -178,4 +178,47 @@ fn main() {
     let compiler_out = out_dir.join("v3_compiler_files.rs");
     fs::write(&compiler_out, compiler_generated)
         .unwrap_or_else(|e| panic!("failed to write {}: {}", compiler_out.display(), e));
+
+    // SG-0 producer-owned generated manifest. The census at
+    // `tests/integration/sg0_census_test.rs` reads this list as the
+    // sole authority for "which .rs files under src/v3/compiler are
+    // generated." Every codegen driver (the `regen_*` binaries plus
+    // the ignored `emit_lens_provenance_snapshot` test) imports the
+    // same manifest and asserts its output path is in it before
+    // writing — so a typo in a regen output path fails loud rather
+    // than silently writing to an uncounted path.
+    //
+    // The manifest lives only in OUT_DIR — it is ephemeral,
+    // reconstructed every build from this list. A hand-edited
+    // manifest file is clobbered on the next `cargo build`; the
+    // spoof surface collapses to this `REGEN_OUTPUTS` literal,
+    // reviewed alongside any real producer change.
+    //
+    // Paths are workspace-relative and sorted for determinism. They
+    // match exactly what the regen drivers write to disk as
+    // committed Rust.
+    const REGEN_OUTPUTS: &[&str] = &[
+        "src/v3/compiler/src/infer_helpers_generated.rs",
+        "src/v3/compiler/src/lens_cost_generated.rs",
+        "src/v3/compiler/src/lens_cost_symbolic_generated.rs",
+        "src/v3/compiler/src/lens_provenance_generated.rs",
+        "src/v3/compiler/src/lens_structural_resolution_generated.rs",
+        "src/v3/compiler/src/lens_unused_parameters_generated.rs",
+    ];
+    let mut manifest = String::from(
+        "// AUTO-GENERATED by build.rs. Do not edit.\n\
+         //\n\
+         // Paths (workspace-relative) of every .rs file under\n\
+         // src/v3/compiler that is produced by a codegen authority\n\
+         // (regen_* binaries today; build.rs-driven include_str!\n\
+         // projections if that surface ever grows into src/).\n\
+         pub static GENERATED_FILES: &[&str] = &[\n",
+    );
+    for path in REGEN_OUTPUTS {
+        manifest.push_str(&format!("    \"{path}\",\n"));
+    }
+    manifest.push_str("];\n");
+    let manifest_out = out_dir.join("v3_generated_files.rs");
+    fs::write(&manifest_out, manifest)
+        .unwrap_or_else(|e| panic!("failed to write {}: {}", manifest_out.display(), e));
 }

src/v3/compiler/src/bin/regen_infer_helpers.rs

@@ -42,6 +42,12 @@ fn main() {
     assert!(output.status.success(), "rustfmt failed");
     let formatted = String::from_utf8(output.stdout).expect("utf8");
 
+    const OUT_REL: &str = "src/v3/compiler/src/infer_helpers_generated.rs";
+    assert!(
+        v3_compiler::generated_files::GENERATED_FILES.contains(&OUT_REL),
+        "SG-0 producer manifest mismatch: `{OUT_REL}` is not in GENERATED_FILES — \
+         add it to REGEN_OUTPUTS in src/v3/compiler/build.rs."
+    );
     let out_path = PathBuf::from(env!("CARGO_MANIFEST_DIR"))
         .join("src")
         .join("infer_helpers_generated.rs");

src/v3/compiler/src/bin/regen_lens_cost.rs

@@ -36,6 +36,12 @@ fn main() {
     assert!(output.status.success(), "rustfmt failed");
     let formatted = String::from_utf8(output.stdout).expect("utf8");
 
+    const OUT_REL: &str = "src/v3/compiler/src/lens_cost_generated.rs";
+    assert!(
+        v3_compiler::generated_files::GENERATED_FILES.contains(&OUT_REL),
+        "SG-0 producer manifest mismatch: `{OUT_REL}` is not in GENERATED_FILES — \
+         add it to REGEN_OUTPUTS in src/v3/compiler/build.rs."
+    );
     let out_path = PathBuf::from(env!("CARGO_MANIFEST_DIR"))
         .join("src")
         .join("lens_cost_generated.rs");

src/v3/compiler/src/bin/regen_lens_cost_symbolic.rs

@@ -42,6 +42,12 @@ fn main() {
     assert!(output.status.success(), "rustfmt failed");
     let formatted = String::from_utf8(output.stdout).expect("utf8");
 
+    const OUT_REL: &str = "src/v3/compiler/src/lens_cost_symbolic_generated.rs";
+    assert!(
+        v3_compiler::generated_files::GENERATED_FILES.contains(&OUT_REL),
+        "SG-0 producer manifest mismatch: `{OUT_REL}` is not in GENERATED_FILES — \
+         add it to REGEN_OUTPUTS in src/v3/compiler/build.rs."
+    );
     let out_path = PathBuf::from(env!("CARGO_MANIFEST_DIR"))
         .join("src")
         .join("lens_cost_symbolic_generated.rs");

src/v3/compiler/src/bin/regen_lens_structural_resolution.rs

@@ -36,6 +36,12 @@ fn main() {
     assert!(output.status.success(), "rustfmt failed");
     let formatted = String::from_utf8(output.stdout).expect("utf8");
 
+    const OUT_REL: &str = "src/v3/compiler/src/lens_structural_resolution_generated.rs";
+    assert!(
+        v3_compiler::generated_files::GENERATED_FILES.contains(&OUT_REL),
+        "SG-0 producer manifest mismatch: `{OUT_REL}` is not in GENERATED_FILES — \
+         add it to REGEN_OUTPUTS in src/v3/compiler/build.rs."
+    );
     let out_path = PathBuf::from(env!("CARGO_MANIFEST_DIR"))
         .join("src")
         .join("lens_structural_resolution_generated.rs");

src/v3/compiler/src/bin/regen_lens_unused_parameters.rs

@@ -36,6 +36,12 @@ fn main() {
     assert!(output.status.success(), "rustfmt failed");
     let formatted = String::from_utf8(output.stdout).expect("utf8");
 
+    const OUT_REL: &str = "src/v3/compiler/src/lens_unused_parameters_generated.rs";
+    assert!(
+        v3_compiler::generated_files::GENERATED_FILES.contains(&OUT_REL),
+        "SG-0 producer manifest mismatch: `{OUT_REL}` is not in GENERATED_FILES — \
+         add it to REGEN_OUTPUTS in src/v3/compiler/build.rs."
+    );
     let out_path = PathBuf::from(env!("CARGO_MANIFEST_DIR"))
         .join("src")
         .join("lens_unused_parameters_generated.rs");

src/v3/compiler/src/lib.rs

@@ -17,6 +17,20 @@
 
 pub mod dag;
 pub mod diagnostics;
+
+/// SG-0 producer-owned generated-file manifest.
+///
+/// `GENERATED_FILES` is the workspace-relative path list of every
+/// `.rs` file under `src/v3/compiler` that is produced by a codegen
+/// authority. The list is emitted by `build.rs` at build time; the
+/// literal is reviewed there. Two consumers today: the `regen_*`
+/// binaries (they assert their output path is in the list before
+/// writing) and the SG-0 census test (it uses the list as the sole
+/// generated/hand-authored partition — no content-marker scanning).
+pub mod generated_files {
+    include!(concat!(env!("OUT_DIR"), "/v3_generated_files.rs"));
+}
+
 pub mod emit;
 pub mod emit_go;
 pub mod emit_python;

src/v3/compiler/tests/integration/m2_lens_provenance_migration_test.rs

@@ -183,6 +183,12 @@ fn render_handwritten_oracle(program_source: &str, file_name: &str) -> String {
 #[test]
 #[ignore]
 fn emit_lens_provenance_snapshot() {
+    const OUT_REL: &str = "src/v3/compiler/src/lens_provenance_generated.rs";
+    assert!(
+        v3_compiler::generated_files::GENERATED_FILES.contains(&OUT_REL),
+        "SG-0 producer manifest mismatch: `{OUT_REL}` is not in GENERATED_FILES — \
+         add it to REGEN_OUTPUTS in src/v3/compiler/build.rs."
+    );
     let fresh = emit_lens_module();
     let out_path = PathBuf::from(env!("CARGO_MANIFEST_DIR"))
         .join("src")