ww/test/wcc/953_arrlit_slice_run.c

/*
 * 953_arrlit_slice_run -- SLIMMED to the one irreducible asymmetric row.
 *
 * The #25/#31 array-literal-slice corpus migrated to fold-2 homes (#5-C6): the
 * value rows -> test/lang/arrlit_slice_test.ww (@test + T2 byte-id); the
 * reject_oob / reject_call / reject_ret rows -> test/wcc/data/arrlit_slice_*
 * runww //ww:error carriers (strong shared substrings, both stages).
 *
 * reject_assign CANNOT move to a runww //ww:error carrier: both stages REJECT an
 * array-LITERAL assigned to a slice, but at DIFFERENT diagnostic LAYERS -- cstage
 * at assignability ("cannot assign [3]int to []i32") and wwstage at the borrow
 * gate ("array literal cannot borrow as a slice here; bind it to a `let` first").
 * BOTH reject CORRECTLY (the borrow is supported only at a `let` init, #31/#33) --
 * this is a benign diag-LAYER divergence, NOT a miscompile, so NO bug ticket. No
 * honest shared substring exists for a #20-non-vacuity carrier, and a build-reject
 * emits no .s (no byte-id surface). It stays a slim C pin asserting rc!=0 BOTH
 * stages -- the position the stages diverge, most worth pinning.
 *
 * Non-vacuity self-check (the pin CAN go RED): `valid_src` assigns a NAMED array
 * (an addressable backing), which the #258 borrow ACCEPTS on both stages (rc==0);
 * it proves the pin discriminates the array-LITERAL reject from a legitimate
 * array-to-slice assign, not "all builds error". Mutation-checked: binding the
 * literal to a `let` first (`let t=[1,2,3]; s=t;`) flips both stages to accept ->
 * the reject leg goes RED (verified).
 */
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/stat.h>
#include <sys/wait.h>

static int
runwait(const char *cmd)
{
	int rc = system(cmd);
	if (rc == -1) return -1;
	if (WIFEXITED(rc)) return WEXITSTATUS(rc);
	return -1;
}

/* reject_assign: an array LITERAL in assign position has no addressable backing
 * -- both stages reject (cstage assignability, wwstage borrow gate). */
static const char *reject_src =
    "package main;\n"
    "export fn main() i32 = {\n"
    "	let s: []i32 = [0, 0];\n"
    "	s = [1, 2, 3];\n"
    "	return s[0];\n"
    "};\n";

/* Vacuity control: a NAMED array assigned as a slice borrow (#258) -- both
 * stages accept. Proves the pin distinguishes accept from reject. */
static const char *valid_src =
    "package main;\n"
    "export fn main() i32 = {\n"
    "	let a: [3]i32 = [1, 2, 3];\n"
    "	let s: []i32 = a[0:1];\n"
    "	s = a;\n"
    "	return s[0];\n"
    "};\n";

/* build_only -- write `src`, build via `driver` (no run). Returns the build
 * exit code (0 = accepted, nonzero = rejected). */
static int
build_only(const char *driver, const char *src, int seq)
{
	char tmpdir[96], srcp[128], outbin[128], rmcmd[160], cmd[1024];
	snprintf(tmpdir, sizeof tmpdir, "/tmp/as_%d_%d", getpid(), seq);
	mkdir(tmpdir, 0755);
	snprintf(srcp, sizeof srcp, "%s/c.ww", tmpdir);
	snprintf(outbin, sizeof outbin, "%s/c", tmpdir);
	snprintf(rmcmd, sizeof rmcmd, "rm -rf %s", tmpdir);

	FILE *f = fopen(srcp, "wb");
	if (!f) { runwait(rmcmd); return -1; }
	fputs(src, f);
	fclose(f);

	snprintf(cmd, sizeof cmd, "timeout 20 %s build -o %s %s >/dev/null 2>&1",
	    driver, outbin, srcp);
	int brc = runwait(cmd);
	runwait(rmcmd);
	return brc;
}

int
main(void)
{
	const char *bin = getenv("BIN");
	if (!bin) bin = "out/bin";
	char absbin[2080];
	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[2120], wdrv[2120];
	snprintf(cdrv, sizeof cdrv, "%s/ww",    bin);
	snprintf(wdrv, sizeof wdrv, "%s/ww_ww", bin);

	int wwpresent = (access(wdrv, X_OK) == 0);
	int fail = 0, seq = 0;

	/* reject leg: both stages must REJECT (rc!=0). */
	if (build_only(cdrv, reject_src, seq++) == 0) {
		fprintf(stderr, "arrlit_slice[cs]: reject_assign ACCEPTED (want reject)\n");
		fail++;
	}
	if (wwpresent && build_only(wdrv, reject_src, seq++) == 0) {
		fprintf(stderr, "arrlit_slice[ww]: reject_assign ACCEPTED (want reject)\n");
		fail++;
	}

	/* vacuity control: both stages must ACCEPT (rc==0). */
	if (build_only(cdrv, valid_src, seq++) != 0) {
		fprintf(stderr, "arrlit_slice[cs]: vacuity control REJECTED (pin may be vacuous)\n");
		fail++;
	}
	if (wwpresent && build_only(wdrv, valid_src, seq++) != 0) {
		fprintf(stderr, "arrlit_slice[ww]: vacuity control REJECTED (pin may be vacuous)\n");
		fail++;
	}

	if (fail) {
		fprintf(stderr, "arrlit_slice: %d checks failed\n", fail);
		return 1;
	}
	printf("arrlit_slice: reject_assign pin ok\n");
	return 0;
}