/* * 684_arr_infer_len — cstage and wwstage agree, byte-for-byte and at * runtime, that a `[_]T = [...]` array infers its length from the * initialiser's element count (task #7, a canonical Hare form). * * The bug: `[_]T` silently miscompiled to a zero-length array. The * parser already left the array type's length child nil as the infer * sentinel (distinct from an explicit `[N]`), but neither checker * stamped the real count — so `len(x)` / `x.len` returned 0 with no * diagnostic (rule-7 silent miscompile). Module-level was worse on * wwstage: `x.len` on ANY global array (even explicit `[N]`) fell to * the SB fallback and mis-emitted `MOVQ len(SB), AX` (linker: * undefined reference to len). * * The fix (BOTH stages, converged byte-identical): * - checker (cmd/wcc/check.c clet + module-level N_LET; * selfhost/cmd/wcc/check.ww inferarraylen): count the array-literal * elements and stamp the length onto the array TYPE. cgen already * keys stride/length/data off the stamped length, so it "just * works" (rob's #7 ruling). A `[_]T` with no array-literal init * can't infer → LOUD error, never a silent zero-length array. * - cgen (selfhost/cmd/wcc/cgenexpr.ww cgdot): a top-level `[N]T` * global's `.len` / `.ptr` pseudo-fields, the wwstage arm that was * missing (cstage cgen.c:8011 already handled it). * * Coverage: `[_]int` / `[_]str` / `[_]u8`, both local and module-level, * `len` read-back and element read-back, dual-stage runtime + asm * byte-id. Mutation-sanity: the old collapse-to-0 fails every `*_len` * row (len would be 0, not the count). Plus three negative rows where * `[_]T` can't infer (no init / non-array init) — both stages must * FAIL the build. * * row | shape | want * ----------------+--------------------------------------+------ * local_int_len | local [_]int=[10,20,30,40], x.len | 4 * local_int_elem | local, x[2] | 30 * mod_int_len | global [_]int=[..], x.len | 4 * mod_int_elem | global, x[2] | 30 * local_str_len | local [_]str=["a","b","c"], x.len | 3 * local_str_elem | local [_]str=["ab","cde"], x[0].len | 2 * mod_str_len | global [_]str=["a","b","c"], x.len | 3 * local_u8_len | local [_]u8=[1..5], x.len | 5 * local_u8_elem | local, x[4] | 5 * local_one_len | local [_]int=[7], x.len (1-elem edge)| 1 * mod_one_len | global [_]int=[7], x.len | 1 * mod_one_elem | global, x[0] | 7 */ #include #include #include #include #include static int runwait(const char *cmd) { int rc = system(cmd); if (rc == -1) return -1; if (WIFEXITED(rc)) return WEXITSTATUS(rc); return -1; } struct row { const char *label; const char *src; int want; }; static const struct row rows[] = { { "local_int_len", "package main;\n" "export fn main() i32 = {\n" "\tlet x: [_]int = [10, 20, 30, 40];\n" "\treturn x.len: i32;\n" "};\n", 4 }, { "local_int_elem", "package main;\n" "export fn main() i32 = {\n" "\tlet x: [_]int = [10, 20, 30, 40];\n" "\treturn x[2]: i32;\n" "};\n", 30 }, { "mod_int_len", "package main;\n" "let x: [_]int = [10, 20, 30, 40];\n" "export fn main() i32 = {\n" "\treturn x.len: i32;\n" "};\n", 4 }, { "mod_int_elem", "package main;\n" "let x: [_]int = [10, 20, 30, 40];\n" "export fn main() i32 = {\n" "\treturn x[2]: i32;\n" "};\n", 30 }, { "local_str_len", "package main;\n" "export fn main() i32 = {\n" "\tlet x: [_]str = [\"a\", \"b\", \"c\"];\n" "\treturn x.len: i32;\n" "};\n", 3 }, { "local_str_elem", "package main;\n" "export fn main() i32 = {\n" "\tlet x: [_]str = [\"ab\", \"cde\"];\n" "\treturn x[0].len: i32;\n" "};\n", 2 }, { "mod_str_len", "package main;\n" "let x: [_]str = [\"a\", \"b\", \"c\"];\n" "export fn main() i32 = {\n" "\treturn x.len: i32;\n" "};\n", 3 }, { "local_u8_len", "package main;\n" "export fn main() i32 = {\n" "\tlet x: [_]u8 = [1u8, 2u8, 3u8, 4u8, 5u8];\n" "\treturn x.len: i32;\n" "};\n", 5 }, { "local_u8_elem", "package main;\n" "export fn main() i32 = {\n" "\tlet x: [_]u8 = [1u8, 2u8, 3u8, 4u8, 5u8];\n" "\treturn x[4]: i32;\n" "};\n", 5 }, /* 1-element edge — the minimal non-empty count; under the old * collapse-to-0 bug `.len` reads 0, not 1, so this row also fails * the mutation. */ { "local_one_len", "package main;\n" "export fn main() i32 = {\n" "\tlet x: [_]int = [7];\n" "\treturn x.len: i32;\n" "};\n", 1 }, { "mod_one_len", "package main;\n" "let x: [_]int = [7];\n" "export fn main() i32 = {\n" "\treturn x.len: i32;\n" "};\n", 1 }, { "mod_one_elem", "package main;\n" "let x: [_]int = [7];\n" "export fn main() i32 = {\n" "\treturn x[0]: i32;\n" "};\n", 7 }, }; /* `[_]T` that can't infer its length — both stages must FAIL the build * (loud diagnostic, not a silent zero-length array). */ static const char *neg[] = { /* no init, local */ "package main;\n" "export fn main() i32 = {\n" "\tlet x: [_]str;\n" "\treturn 0;\n" "};\n", /* no init, module-level */ "package main;\n" "let x: [_]int;\n" "export fn main() i32 = { return 0; };\n", /* non-array initialiser */ "package main;\n" "export fn main() i32 = {\n" "\tlet x: [_]int = 5;\n" "\treturn 0;\n" "};\n", }; static int run_driver(const char *driver, const struct row *r, int i) { char tmpdir[64], src[128], outbin[128], rmcmd[160], cmd[1024]; snprintf(tmpdir, sizeof tmpdir, "/tmp/ail_%d_d_%d", getpid(), i); mkdir(tmpdir, 0755); snprintf(src, sizeof src, "%s/ail_%d_%d.ww", tmpdir, getpid(), i); snprintf(outbin, sizeof outbin, "%s/ail_%d_%d", tmpdir, getpid(), i); snprintf(rmcmd, sizeof rmcmd, "rm -rf %s", tmpdir); FILE *f = fopen(src, "wb"); if (!f) { runwait(rmcmd); return -1; } fputs(r->src, f); fclose(f); snprintf(cmd, sizeof cmd, "%s build -o %s %s 2>/dev/null", driver, outbin, src); if (runwait(cmd) != 0) { fprintf(stderr, "row[%s]: build via %s failed\n", r->label, driver); runwait(rmcmd); return -1; } int got = runwait(outbin); runwait(rmcmd); return got; } /* build_should_fail — a `[_]T` that can't infer must error on `driver`; * returns 0 when the build correctly FAILS, non-zero when it wrongly * succeeded. */ static int build_should_fail(const char *driver, const char *src, int i) { char tmpdir[64], s[128], outbin[128], rmcmd[160], cmd[1024]; snprintf(tmpdir, sizeof tmpdir, "/tmp/ailn_%d_d_%d", getpid(), i); mkdir(tmpdir, 0755); snprintf(s, sizeof s, "%s/ailn_%d_%d.ww", tmpdir, getpid(), i); snprintf(outbin, sizeof outbin, "%s/ailn_%d_%d", tmpdir, getpid(), i); snprintf(rmcmd, sizeof rmcmd, "rm -rf %s", tmpdir); FILE *f = fopen(s, "wb"); if (!f) { runwait(rmcmd); return -1; } fputs(src, f); fclose(f); snprintf(cmd, sizeof cmd, "%s build -o %s %s 2>/dev/null", driver, outbin, s); int rc = runwait(cmd); runwait(rmcmd); return rc == 0 ? -1 : 0; /* build must NOT succeed */ } /* asm_byte_identical — w6c vs w6c_ww .s for the same source must match. */ static int asm_byte_identical(const char *bin, const struct row *r, int i) { char src[64], cs[64], ws[64], cmd[1024]; snprintf(src, sizeof src, "/tmp/ail_asm_%d_%d.ww", getpid(), i); snprintf(cs, sizeof cs, "/tmp/ail_asm_%d_%d_c.s", getpid(), i); snprintf(ws, sizeof ws, "/tmp/ail_asm_%d_%d_w.s", getpid(), i); FILE *f = fopen(src, "wb"); if (!f) return -1; fputs(r->src, f); fclose(f); snprintf(cmd, sizeof cmd, "%s/w6c -o %s %s 2>/dev/null", bin, cs, src); if (runwait(cmd) != 0) { fprintf(stderr, "row[%s]: w6c errored\n", r->label); unlink(src); return -1; } snprintf(cmd, sizeof cmd, "%s/w6c_ww -o %s %s 2>/dev/null", bin, ws, src); if (runwait(cmd) != 0) { fprintf(stderr, "row[%s]: w6c_ww errored\n", r->label); unlink(src); unlink(cs); return -1; } FILE *fc = fopen(cs, "rb"); FILE *fw = fopen(ws, "rb"); int rc = 0; if (!fc || !fw) { rc = -1; } else { for (;;) { int a = fgetc(fc); int b = fgetc(fw); if (a != b) { rc = -1; break; } if (a == EOF) break; } } if (fc) fclose(fc); if (fw) fclose(fw); if (rc != 0) fprintf(stderr, "row[%s]: cstage vs wwstage asm differs\n", r->label); unlink(src); unlink(cs); unlink(ws); return rc; } int main(void) { const char *bin = getenv("BIN"); if (!bin) bin = "out/bin"; char absbin[1024]; if (bin[0] != '/') { char cwd[1024]; if (getcwd(cwd, sizeof cwd) == NULL) return 1; snprintf(absbin, sizeof absbin, "%s/%s", cwd, bin); bin = absbin; } char cdrv[1024]; snprintf(cdrv, sizeof cdrv, "%s/ww", bin); char wdrv[1024]; snprintf(wdrv, sizeof wdrv, "%s/ww_ww", bin); struct { const char *name; const char *path; int gated_on_existence; } drivers[] = { { "cstage", cdrv, 0 }, { "wwstage", wdrv, 1 }, { NULL, NULL, 0 }, }; int n = (int)(sizeof rows / sizeof rows[0]); int nn = (int)(sizeof neg / sizeof neg[0]); int total = 0, fail = 0; for (int d = 0; drivers[d].name; d++) { if (drivers[d].gated_on_existence && access(drivers[d].path, X_OK) != 0) { fprintf(stderr, "arr_infer_len: skip %s (no %s)\n", drivers[d].name, drivers[d].path); continue; } for (int i = 0; i < n; i++) { int got = run_driver(drivers[d].path, &rows[i], i); total++; if (got != rows[i].want) { fprintf(stderr, "arr_infer_len[%s][%s]: exit=%d want=%d\n", drivers[d].name, rows[i].label, got, rows[i].want); fail++; } } for (int i = 0; i < nn; i++) { total++; if (build_should_fail(drivers[d].path, neg[i], 100 + i) != 0) { fprintf(stderr, "arr_infer_len[%s][neg%d]: built ok, " "expected a loud error\n", drivers[d].name, i); fail++; } } } if (access(wdrv, X_OK) == 0) { for (int i = 0; i < n; i++) { total++; if (asm_byte_identical(bin, &rows[i], i) != 0) fail++; } } if (fail) { fprintf(stderr, "arr_infer_len: %d/%d fixtures failed\n", fail, total); return 1; } printf("arr_infer_len: %d/%d ok\n", total, total); return 0; }