wcc/cgen: #146 wwstage str ==/!= via rt_streq, not ptr-only CMPQ (the #154 ww-twin)

wwstage compiled str ==/!= as a single CMPQ on the eager-eval'd ptr word (len ignored), so two distinct-pointer equal-content strings compared unequal. cstage was already correct (CALLs rt_streq, the #154 cbinop fix). The wwstage cgbin had no str-awareness -- every comparison fell to the generic CMPQ tail; the #154 fix was never mirrored. wwstage-only: a cgstreqpush helper + a str ==/!= branch at the top of cgbin (before the generic eval collapses the header), byte-matching cstage cbinop:4564-4623 -- push rhs/lhs (len,ptr), POPQ DI/SI/DX/CX, CALL rt_streq, XORQ $1 for !=. Gated on typeisstr (= cstage node_isstr, which also catches module-global str idents). cstage cgen unchanged (w6c md5 unchanged). The str== .s is byte-identical cs==ww for local, global, aliased, chained, and condition operands. Graduates 3 lib byte-id pins (test/wcc/989_lib_byteid #59.1 asciitest, #59.11 toktest, #59.12 asttest) M_DIVERGE->M_ID -- they used == on str and were pinned divergent because of this bug; now byte-identical. byte-id 990-997 8/8. test/wcc/827 table-driven.
2026-06-08 23:49:16 +09:00
parent 83025b03a6
commit 5dd239d01e
6 changed files with 496 additions and 3 deletions
--- a/7
+++ b/7
@@ -255,6 +255,7 @@ TESTS	= $(BIN)/test_smoke $(BIN)/test_lex $(BIN)/test_parse $(BIN)/test_check \
 	  $(BIN)/test_inferred_float_global \
 	  $(BIN)/test_errfirst_union_try \
 	  $(BIN)/test_alias_tuple_coerce \
+	  $(BIN)/test_str_eq \
 	  $(BIN)/test_slice_str_global_zero \
 	  $(BIN)/test_slice_literal_global \
 	  $(BIN)/test_global_arr_elem_field \
@@ -693,6 +694,12 @@ $(BIN)/test_alias_tuple_coerce: test/wcc/826_alias_tuple_coerce.c $(BIN)/ww \
 		$(LIB)/libwwrt.a | $(BIN)
 	$(CC) $(CFLAGS) -o $@ $<

+$(BIN)/test_str_eq: test/wcc/827_str_eq.c $(BIN)/ww \
+		$(BIN)/w6c $(BIN)/w6a $(BIN)/w6l \
+		$(BIN)/ww_ww $(BIN)/w6c_ww $(BIN)/w6a_ww $(BIN)/w6l_ww \
+		$(LIB)/libwwrt.a | $(BIN)
+	$(CC) $(CFLAGS) -o $@ $<
+
 $(BIN)/test_def_arr_infer_len: test/wcc/814_def_arr_infer_len.c $(BIN)/ww \
 		$(BIN)/w6c $(BIN)/w6a $(BIN)/w6l \
 		$(BIN)/ww_ww $(BIN)/w6c_ww $(BIN)/w6a_ww $(BIN)/w6l_ww \
--- a/selfhost/cmd/w6c/main.combined.ww
+++ b/selfhost/cmd/w6c/main.combined.ww
@@ -26856,6 +26856,43 @@ fn cgun(c: *cgen, n: *node) void = {
 	return;
 };

+// cgstreqpush — push one str operand's (len, then ptr) header words for
+// the rt_streq content-compare in cgbin. Mirrors cstage cgen.c:4568-4615:
+// an ident loads its 2-word header (ptr+len, NOT cap) from name(SB) for a
+// module-global str (#154 let_islet branch) or BP+off for a local; a
+// non-ident evals via cgexpr (AX=ptr, BX=len) and pushes BX then AX. Push
+// order is len then ptr so the matching POPQ pops ptr first.
+fn cgstreqpush(c: *cgen, op: *node) void = {
+	if (op.kind == nkind.N_IDENT) {
+		let nm: str = op.str;
+		let lc: *local = localfindnode(c, nm);
+		if (lc == nil && isletvar(c, nm)) {
+			emitline("\tLEAQ\t");
+			emitsymnamehint(c, nm, c.curmod);
+			emitline("(SB), BX\n");
+			emitline("\tMOVQ\t8(BX), AX\n");
+			emitline("\tPUSHQ\tAX\n");
+			emitline("\tMOVQ\t(BX), AX\n");
+			emitline("\tPUSHQ\tAX\n");
+			return;
+		};
+		let off: i32 = 0;
+		if (lc != nil) { off = lc.off; };
+		emitline("\tMOVQ\t");
+		emitoff((off + 8): i64);
+		emitline("(BP), AX\n");
+		emitline("\tPUSHQ\tAX\n");
+		emitline("\tMOVQ\t");
+		emitoff(off: i64);
+		emitline("(BP), AX\n");
+		emitline("\tPUSHQ\tAX\n");
+		return;
+	};
+	cgexpr(c, op);
+	emitline("\tPUSHQ\tBX\n");
+	emitline("\tPUSHQ\tAX\n");
+};
+
 fn cgbin(c: *cgen, n: *node) void = {
 	// Short-circuit `&&` / `||`. Operands are bool (0/1); the type
 	// checker enforces it. Eval LHS into AX, branch over RHS on the
@@ -26877,6 +26914,26 @@ fn cgbin(c: *cgen, n: *node) void = {
 		return;
 	};

+	// #146 (#154 ww-twin): str ==/!= is a CONTENT compare via rt_streq,
+	// not a ptr compare. Must run before the generic eager-eval tail
+	// below collapses each str header to its ptr word (AX). Push rhs
+	// then lhs (len, ptr each); POPQ DI/SI/DX/CX lands a.ptr,a.len,
+	// b.ptr,b.len per rt/streq.s; CALL rt_streq -> AX in {0,1}; XOR 1
+	// for !=. The gate reads the checker stamp (typeisstr) exactly like
+	// cstage node_isstr. Byte-identical to cstage cbinop (cmd/w6c/
+	// cgen.c:4564-4623). cstage was fixed by #154; this is its mirror.
+	if ((n.op == tkind.TK_EQ || n.op == tkind.TK_NEQ)
+	    && n.lhs != nil && n.rhs != nil
+	    && typeisstr(n.lhs.type_: *tinfo)
+	    && typeisstr(n.rhs.type_: *tinfo)) {
+		cgstreqpush(c, n.rhs);
+		cgstreqpush(c, n.lhs);
+		emitline("\tPOPQ\tDI\n\tPOPQ\tSI\n\tPOPQ\tDX\n\tPOPQ\tCX\n");
+		emitline("\tCALL\trt_streq(SB)\n");
+		if (n.op == tkind.TK_NEQ) { emitline("\tXORQ\t$1, AX\n"); };
+		return;
+	};
+
 	let unsignd: bool = nodeisunsigned(c, n.lhs);
 	if (!unsignd) { unsignd = nodeisunsigned(c, n.rhs); };

--- a/selfhost/cmd/wcc/cgenexpr.ww
+++ b/selfhost/cmd/wcc/cgenexpr.ww
@@ -5273,6 +5273,43 @@ fn cgun(c: *cgen, n: *node) void = {
 	return;
 };

+// cgstreqpush — push one str operand's (len, then ptr) header words for
+// the rt_streq content-compare in cgbin. Mirrors cstage cgen.c:4568-4615:
+// an ident loads its 2-word header (ptr+len, NOT cap) from name(SB) for a
+// module-global str (#154 let_islet branch) or BP+off for a local; a
+// non-ident evals via cgexpr (AX=ptr, BX=len) and pushes BX then AX. Push
+// order is len then ptr so the matching POPQ pops ptr first.
+fn cgstreqpush(c: *cgen, op: *node) void = {
+	if (op.kind == nkind.N_IDENT) {
+		let nm: str = op.str;
+		let lc: *local = localfindnode(c, nm);
+		if (lc == nil && isletvar(c, nm)) {
+			emitline("\tLEAQ\t");
+			emitsymnamehint(c, nm, c.curmod);
+			emitline("(SB), BX\n");
+			emitline("\tMOVQ\t8(BX), AX\n");
+			emitline("\tPUSHQ\tAX\n");
+			emitline("\tMOVQ\t(BX), AX\n");
+			emitline("\tPUSHQ\tAX\n");
+			return;
+		};
+		let off: i32 = 0;
+		if (lc != nil) { off = lc.off; };
+		emitline("\tMOVQ\t");
+		emitoff((off + 8): i64);
+		emitline("(BP), AX\n");
+		emitline("\tPUSHQ\tAX\n");
+		emitline("\tMOVQ\t");
+		emitoff(off: i64);
+		emitline("(BP), AX\n");
+		emitline("\tPUSHQ\tAX\n");
+		return;
+	};
+	cgexpr(c, op);
+	emitline("\tPUSHQ\tBX\n");
+	emitline("\tPUSHQ\tAX\n");
+};
+
 fn cgbin(c: *cgen, n: *node) void = {
 	// Short-circuit `&&` / `||`. Operands are bool (0/1); the type
 	// checker enforces it. Eval LHS into AX, branch over RHS on the
@@ -5294,6 +5331,26 @@ fn cgbin(c: *cgen, n: *node) void = {
 		return;
 	};

+	// #146 (#154 ww-twin): str ==/!= is a CONTENT compare via rt_streq,
+	// not a ptr compare. Must run before the generic eager-eval tail
+	// below collapses each str header to its ptr word (AX). Push rhs
+	// then lhs (len, ptr each); POPQ DI/SI/DX/CX lands a.ptr,a.len,
+	// b.ptr,b.len per rt/streq.s; CALL rt_streq -> AX in {0,1}; XOR 1
+	// for !=. The gate reads the checker stamp (typeisstr) exactly like
+	// cstage node_isstr. Byte-identical to cstage cbinop (cmd/w6c/
+	// cgen.c:4564-4623). cstage was fixed by #154; this is its mirror.
+	if ((n.op == tkind.TK_EQ || n.op == tkind.TK_NEQ)
+	    && n.lhs != nil && n.rhs != nil
+	    && typeisstr(n.lhs.type_: *tinfo)
+	    && typeisstr(n.rhs.type_: *tinfo)) {
+		cgstreqpush(c, n.rhs);
+		cgstreqpush(c, n.lhs);
+		emitline("\tPOPQ\tDI\n\tPOPQ\tSI\n\tPOPQ\tDX\n\tPOPQ\tCX\n");
+		emitline("\tCALL\trt_streq(SB)\n");
+		if (n.op == tkind.TK_NEQ) { emitline("\tXORQ\t$1, AX\n"); };
+		return;
+	};
+
 	let unsignd: bool = nodeisunsigned(c, n.lhs);
 	if (!unsignd) { unsignd = nodeisunsigned(c, n.rhs); };

--- a/selfhost/cmd/wwdump/main.combined.ww
+++ b/selfhost/cmd/wwdump/main.combined.ww
@@ -26856,6 +26856,43 @@ fn cgun(c: *cgen, n: *node) void = {
 	return;
 };

+// cgstreqpush — push one str operand's (len, then ptr) header words for
+// the rt_streq content-compare in cgbin. Mirrors cstage cgen.c:4568-4615:
+// an ident loads its 2-word header (ptr+len, NOT cap) from name(SB) for a
+// module-global str (#154 let_islet branch) or BP+off for a local; a
+// non-ident evals via cgexpr (AX=ptr, BX=len) and pushes BX then AX. Push
+// order is len then ptr so the matching POPQ pops ptr first.
+fn cgstreqpush(c: *cgen, op: *node) void = {
+	if (op.kind == nkind.N_IDENT) {
+		let nm: str = op.str;
+		let lc: *local = localfindnode(c, nm);
+		if (lc == nil && isletvar(c, nm)) {
+			emitline("\tLEAQ\t");
+			emitsymnamehint(c, nm, c.curmod);
+			emitline("(SB), BX\n");
+			emitline("\tMOVQ\t8(BX), AX\n");
+			emitline("\tPUSHQ\tAX\n");
+			emitline("\tMOVQ\t(BX), AX\n");
+			emitline("\tPUSHQ\tAX\n");
+			return;
+		};
+		let off: i32 = 0;
+		if (lc != nil) { off = lc.off; };
+		emitline("\tMOVQ\t");
+		emitoff((off + 8): i64);
+		emitline("(BP), AX\n");
+		emitline("\tPUSHQ\tAX\n");
+		emitline("\tMOVQ\t");
+		emitoff(off: i64);
+		emitline("(BP), AX\n");
+		emitline("\tPUSHQ\tAX\n");
+		return;
+	};
+	cgexpr(c, op);
+	emitline("\tPUSHQ\tBX\n");
+	emitline("\tPUSHQ\tAX\n");
+};
+
 fn cgbin(c: *cgen, n: *node) void = {
 	// Short-circuit `&&` / `||`. Operands are bool (0/1); the type
 	// checker enforces it. Eval LHS into AX, branch over RHS on the
@@ -26877,6 +26914,26 @@ fn cgbin(c: *cgen, n: *node) void = {
 		return;
 	};

+	// #146 (#154 ww-twin): str ==/!= is a CONTENT compare via rt_streq,
+	// not a ptr compare. Must run before the generic eager-eval tail
+	// below collapses each str header to its ptr word (AX). Push rhs
+	// then lhs (len, ptr each); POPQ DI/SI/DX/CX lands a.ptr,a.len,
+	// b.ptr,b.len per rt/streq.s; CALL rt_streq -> AX in {0,1}; XOR 1
+	// for !=. The gate reads the checker stamp (typeisstr) exactly like
+	// cstage node_isstr. Byte-identical to cstage cbinop (cmd/w6c/
+	// cgen.c:4564-4623). cstage was fixed by #154; this is its mirror.
+	if ((n.op == tkind.TK_EQ || n.op == tkind.TK_NEQ)
+	    && n.lhs != nil && n.rhs != nil
+	    && typeisstr(n.lhs.type_: *tinfo)
+	    && typeisstr(n.rhs.type_: *tinfo)) {
+		cgstreqpush(c, n.rhs);
+		cgstreqpush(c, n.lhs);
+		emitline("\tPOPQ\tDI\n\tPOPQ\tSI\n\tPOPQ\tDX\n\tPOPQ\tCX\n");
+		emitline("\tCALL\trt_streq(SB)\n");
+		if (n.op == tkind.TK_NEQ) { emitline("\tXORQ\t$1, AX\n"); };
+		return;
+	};
+
 	let unsignd: bool = nodeisunsigned(c, n.lhs);
 	if (!unsignd) { unsignd = nodeisunsigned(c, n.rhs); };

--- a/test/wcc/827_str_eq.c
+++ b/test/wcc/827_str_eq.c
@@ -0,0 +1,315 @@
+/*
+ * 827_str_eq — str `==` / `!=` is a CONTENT compare (rt_streq), not a
+ * pointer compare. #146 (the ww-twin of the #154 cstage fix).
+ *
+ * THE BUG (wwstage-only; cstage was already correct via #154): wwstage
+ * cgbin (selfhost/cmd/wcc/cgenexpr.ww) had NO str-awareness, so every
+ * `==`/`!=` fell to the generic comparison tail — a single `CMPQ BX, AX`
+ * on the eager-eval'd registers. For a str, eager-eval collapses the
+ * 3-word header to its ptr word, so the compare became ptr-vs-ptr: two
+ * DISTINCT-pointer equal-content strings answered FALSE on wwstage while
+ * cstage (which CALLs rt_streq) answered TRUE. THE divergence row is
+ * eq_dup_true: `let a="abc"; let b=strings.dup("abc"); a==b`.
+ *
+ * THE FIX: cgbin now has a str ==/!= branch at the top (before the
+ * generic eval), mirroring cstage cgen.c cbinop:4564-4623 — push rhs
+ * then lhs (len, ptr each), POPQ DI/SI/DX/CX = a.ptr,a.len,b.ptr,b.len
+ * (rt/streq.s ABI), CALL rt_streq -> AX in {0,1}, XORQ $1 for !=.
+ *
+ * Two row sets:
+ *   runrows  — built+RUN on BOTH drivers (need strings.dup for a
+ *              distinct-pointer copy, so they `import strings` and build
+ *              via `ww` which links the lib). These pin RUNTIME
+ *              correctness; eq_dup_true/ne_dup_false are mutation-sane
+ *              (pre-fix wwstage gave the wrong ptr-compare answer).
+ *   asmrows  — import-free single files run straight through w6c /
+ *              w6c_ww for the BYTE-ID headline (w6c compiles one file and
+ *              can't resolve strings.dup, so the import rows can't be
+ *              byte-id'd directly; these import-free str==/!= sources
+ *              exercise the identical cgbin branch and pin cs==ww `.s`).
+ *
+ *   runrows                                          | want
+ *   -------------------------------------------------+------
+ *   eq_dup_true   a=="abc", b=dup("abc"); a==b       | 1   (THE bug)
+ *   ne_dup_false  a=="abc", b=dup("abc"); a!=b       | 0   (!= twin)
+ *   diff_content  "abc"=="abd"                        | 0   (control)
+ *   eq_self       a="x"; a==a                         | 1   (same ptr)
+ *   empty         a="", b=dup(""); a==b               | 1   (len-0 edge)
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.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;
+}
+
+struct row { const char *label; const char *src; int want; };
+
+static const struct row runrows[] = {
+	/* eq_dup_true — THE regression pin: distinct pointer, equal
+	 * content. Pre-fix wwstage ptr-compared -> 0 (WRONG); cstage
+	 * CALLs rt_streq -> 1. */
+	{ "eq_dup_true",
+	  "package main;\n"
+	  "import strings;\n"
+	  "export fn main() i32 = {\n"
+	  "\tlet a: str = \"abc\";\n"
+	  "\tlet b: str = strings.dup(\"abc\");\n"
+	  "\tif (a == b) { return 1; };\n"
+	  "\treturn 0;\n"
+	  "};\n",
+	  1 },
+
+	/* ne_dup_false — the != twin: distinct pointer, equal content, so
+	 * `!=` is FALSE. Pre-fix wwstage ptr-compared -> != true (WRONG). */
+	{ "ne_dup_false",
+	  "package main;\n"
+	  "import strings;\n"
+	  "export fn main() i32 = {\n"
+	  "\tlet a: str = \"abc\";\n"
+	  "\tlet b: str = strings.dup(\"abc\");\n"
+	  "\tif (a != b) { return 1; };\n"
+	  "\treturn 0;\n"
+	  "};\n",
+	  0 },
+
+	/* diff_content — distinct content; both stages agree (control). */
+	{ "diff_content",
+	  "package main;\n"
+	  "export fn main() i32 = {\n"
+	  "\tif (\"abc\" == \"abd\") { return 1; };\n"
+	  "\treturn 0;\n"
+	  "};\n",
+	  0 },
+
+	/* eq_self — same pointer, equal content; both stages agree. */
+	{ "eq_self",
+	  "package main;\n"
+	  "export fn main() i32 = {\n"
+	  "\tlet a: str = \"x\";\n"
+	  "\tif (a == a) { return 1; };\n"
+	  "\treturn 0;\n"
+	  "};\n",
+	  1 },
+
+	/* empty — len-0 edge: rt_streq must match two empty strings. */
+	{ "empty",
+	  "package main;\n"
+	  "import strings;\n"
+	  "export fn main() i32 = {\n"
+	  "\tlet a: str = \"\";\n"
+	  "\tlet b: str = strings.dup(\"\");\n"
+	  "\tif (a == b) { return 1; };\n"
+	  "\treturn 0;\n"
+	  "};\n",
+	  1 },
+};
+
+/* Import-free sources for the byte-id pass (w6c compiles a single file
+ * and can't resolve cross-module strings.dup). Each exercises the cgbin
+ * str ==/!= branch; the `.s` must be identical cstage vs wwstage. */
+static const struct row asmrows[] = {
+	/* be_eq_local — local str == local str (ident operand load). */
+	{ "be_eq_local",
+	  "package main;\n"
+	  "export fn main() i32 = {\n"
+	  "\tlet a: str = \"abc\";\n"
+	  "\tlet b: str = \"abd\";\n"
+	  "\tif (a == b) { return 1; };\n"
+	  "\treturn 0;\n"
+	  "};\n",
+	  0 },
+
+	/* be_ne_local — the != twin (pins the XORQ $1, AX). */
+	{ "be_ne_local",
+	  "package main;\n"
+	  "export fn main() i32 = {\n"
+	  "\tlet a: str = \"abc\";\n"
+	  "\tlet b: str = \"abd\";\n"
+	  "\tif (a != b) { return 1; };\n"
+	  "\treturn 0;\n"
+	  "};\n",
+	  1 },
+
+	/* be_eq_strlit — strlit == strlit (non-ident cgexpr operand). */
+	{ "be_eq_strlit",
+	  "package main;\n"
+	  "export fn main() i32 = {\n"
+	  "\tif (\"abc\" == \"abc\") { return 1; };\n"
+	  "\treturn 0;\n"
+	  "};\n",
+	  1 },
+
+	/* be_eq_global — module-GLOBAL str == global str. This is the
+	 * raison d'etre of the typeisstr gate (vs the spec's nodeisstr,
+	 * whose N_IDENT arm keys on localfindnode and returns false for a
+	 * global, leaving a latent cs!=ww hole). The cgstreqpush global arm
+	 * (LEAQ name(SB)) must byte-match cstage's #154 let_islet branch. */
+	{ "be_eq_global",
+	  "package main;\n"
+	  "let g: str = \"abc\";\n"
+	  "let h: str = \"abd\";\n"
+	  "export fn main() i32 = {\n"
+	  "\tif (g == h) { return 1; };\n"
+	  "\treturn 0;\n"
+	  "};\n",
+	  0 },
+};
+
+static int
+run_driver(const char *driver, const struct row *r, int i)
+{
+	char src[64], tmpdir[64], cmd[1024];
+	snprintf(src, sizeof src, "/tmp/seq_%d_%d.ww", getpid(), i);
+	snprintf(tmpdir, sizeof tmpdir, "/tmp/seq_%d_d_%d", getpid(), i);
+
+	FILE *f = fopen(src, "wb");
+	if (!f) return -1;
+	fputs(r->src, f);
+	fclose(f);
+
+	mkdir(tmpdir, 0755);
+	snprintf(cmd, sizeof cmd, "cd %s && %s build %s 2>/dev/null",
+	    tmpdir, driver, src);
+	if (runwait(cmd) != 0) {
+		fprintf(stderr, "row[%s]: build via %s failed\n",
+		    r->label, driver);
+		unlink(src); rmdir(tmpdir);
+		return -1;
+	}
+
+	const char *base = strrchr(src, '/');
+	base = base ? base + 1 : src;
+	char outbin[128];
+	snprintf(outbin, sizeof outbin, "%s/%s", tmpdir, base);
+	char *dot = strrchr(outbin, '.');
+	if (dot && strcmp(dot, ".ww") == 0) *dot = '\0';
+	int got = runwait(outbin);
+
+	unlink(src); unlink(outbin); rmdir(tmpdir);
+	return got;
+}
+
+/* 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/seq_asm_%d_%d.ww", getpid(), i);
+	snprintf(cs,  sizeof cs,  "/tmp/seq_asm_%d_%d_c.s", getpid(), i);
+	snprintf(ws,  sizeof ws,  "/tmp/seq_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 nrun = (int)(sizeof runrows / sizeof runrows[0]);
+	int nasm = (int)(sizeof asmrows / sizeof asmrows[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, "str_eq: skip %s (no %s)\n",
+			    drivers[d].name, drivers[d].path);
+			continue;
+		}
+		for (int i = 0; i < nrun; i++) {
+			int got = run_driver(drivers[d].path, &runrows[i], i);
+			total++;
+			if (got != runrows[i].want) {
+				fprintf(stderr,
+				    "str_eq[%s][%s]: exit=%d want=%d\n",
+				    drivers[d].name, runrows[i].label,
+				    got, runrows[i].want);
+				fail++;
+			}
+		}
+	}
+
+	if (access(wdrv, X_OK) == 0) {
+		for (int i = 0; i < nasm; i++) {
+			total++;
+			if (asm_byte_identical(bin, &asmrows[i], i) != 0)
+				fail++;
+		}
+	}
+
+	if (fail) {
+		fprintf(stderr, "str_eq: %d/%d fixtures failed\n", fail, total);
+		return 1;
+	}
+	printf("str_eq: %d/%d ok\n", total, total);
+	return 0;
+}
--- a/test/wcc/989_lib_byteid.c
+++ b/test/wcc/989_lib_byteid.c
@@ -133,7 +133,7 @@ static const struct ent ents[] = {
 	  .mode = M_ID, .sentinel = "package libc;", .moddir = "lib/c/libc" },
 	/* -------- documented-allowed cs≠ww (task #59) ------------ */
 	{ .fixture = "lib/ascii/asciitest.ww",
-	  .mode = M_DIVERGE, .cite = "#59.1" },
+	  .mode = M_ID, .cite = "#59.1 graduated by #146 str==" },
 	/* #59.2 bufio graduated to M_ID above (#129 fix) */
 	{ .fixture = "lib/encoding/base64/base64_test.ww",
 	  .mode = M_DIVERGE, .cite = "#59.3" },
@@ -148,10 +148,10 @@ static const struct ent ents[] = {
 	  .mode = M_DIVERGE, .cite = "#59.9" },
 	/* #59.10 stoftest graduated to M_ID above (#62 fix) */
 	{ .fixture = "lib/ww/lex/toktest.ww",
-	  .mode = M_DIVERGE, .cite = "#59.11" },
+	  .mode = M_ID, .cite = "#59.11 graduated by #146 str==" },
 	/* asttest resolves `import tok` via -I lib/ww/lex, cf 905 */
 	{ .fixture = "lib/ww/asttest.ww", .inc = "lib/ww/lex",
-	  .mode = M_DIVERGE, .cite = "#59.12" },
+	  .mode = M_ID, .cite = "#59.12 graduated by #146 str==" },
 	/* -------- wwstage front-end gaps (task #59) -------------- */
 	{ .fixture = "lib/crypto/sha256/sha256_test.ww",
 	  .mode = M_WWREJECT, .cite = "#59.13" },