types: add INT/UINT limit constants, derived from size(int) (#114)

ww's int/uint are machine words (8B on amd64, type.c:58), not the 4B
Hare gives them on amd64 (arch+x86_64.ha maps INT_MAX->I32_MAX). So the
limits can't alias a per-arch literal; they DERIVE from size(int) the
Go way (cf math.MaxInt), staying correct on any word width:

  INT_MAX:  int  = (1 << (size(int)*8 - 1)) - 1
  INT_MIN:  int  = -1 << (size(int)*8 - 1)
  UINT_MIN: uint = 0
  UINT_MAX: uint = ~(0: uint)

All four const-fold in def-init; on amd64 they evaluate to I64_MAX,
I64_MIN, 0, U64_MAX. UINT_MAX uses the all-ones complement to dodge the
1<<64 overflow. Per the user ruling (2026-05-26): derived, not literal.

Probe 959_types_intlim_run asserts each value vs both the literal and
the i64/u64 limit const, plus wrap-through-i32 arithmetic usability.
combined.ww regenerated for all 5 selfhost tools + smoke (all embed
lib/types).

Makefile

@@ -336,6 +336,7 @@ TESTS	= $(BIN)/test_smoke $(BIN)/test_lex $(BIN)/test_parse $(BIN)/test_check \
 	  $(BIN)/test_floats_run \
 	  $(BIN)/test_size_type_run \
 	  $(BIN)/test_types_sizelim_run \
+	  $(BIN)/test_types_intlim_run \
 	  $(BIN)/test_bufio_run $(BIN)/test_random_run
 
 $(BIN)/test_smoke: test/wcc/000_smoke.c $(LIB)/libwcc.a | $(BIN)
@@ -1091,6 +1092,10 @@ $(BIN)/test_types_sizelim_run: test/wcc/958_types_sizelim_run.c $(BIN)/ww \
 		$(BIN)/w6c $(BIN)/w6a $(BIN)/w6l $(LIB)/libwwrt.a | $(BIN)
 	$(CC) $(CFLAGS) -o $@ $<
 
+$(BIN)/test_types_intlim_run: test/wcc/959_types_intlim_run.c $(BIN)/ww \
+		$(BIN)/w6c $(BIN)/w6a $(BIN)/w6l $(LIB)/libwwrt.a | $(BIN)
+	$(CC) $(CFLAGS) -o $@ $<
+
 $(BIN)/test_f64crossmod_run: test/wcc/953_f64crossmod_run.c $(BIN)/ww \
 		$(BIN)/w6c $(BIN)/w6c_ww $(BIN)/w6a $(BIN)/w6l \
 		$(LIB)/libwwrt.a | $(BIN)

lib/types/types.ww

@@ -24,6 +24,14 @@ def U16_MIN: u16 = 0;
 def U32_MIN: u32 = 0;
 def U64_MIN: u64 = 0;
 
+// int/uint are machine-word (Go-style, type.c:58); limits derived from
+// size(int) per #114 + user ruling; cf Go math.MaxInt; diverges from
+// Hare's per-arch literal (arch+x86_64.ha) because ww's int is 64-bit.
+def INT_MAX:  int  = (1 << (size(int)*8 - 1)) - 1;
+def INT_MIN:  int  = -1 << (size(int)*8 - 1);
+def UINT_MIN: uint = 0;
+def UINT_MAX: uint = ~(0: uint);
+
 // size is 8B on amd64; no cast needed (size ∈ unsigned class per #113).
 def SIZE_MIN: size = U64_MIN;
 def SIZE_MAX: size = U64_MAX;

selfhost/cmd/w6a/main.combined.ww

@@ -776,6 +776,14 @@ def U16_MIN: u16 = 0;
 def U32_MIN: u32 = 0;
 def U64_MIN: u64 = 0;
 
+// int/uint are machine-word (Go-style, type.c:58); limits derived from
+// size(int) per #114 + user ruling; cf Go math.MaxInt; diverges from
+// Hare's per-arch literal (arch+x86_64.ha) because ww's int is 64-bit.
+def INT_MAX:  int  = (1 << (size(int)*8 - 1)) - 1;
+def INT_MIN:  int  = -1 << (size(int)*8 - 1);
+def UINT_MIN: uint = 0;
+def UINT_MAX: uint = ~(0: uint);
+
 // size is 8B on amd64; no cast needed (size ∈ unsigned class per #113).
 def SIZE_MIN: size = U64_MIN;
 def SIZE_MAX: size = U64_MAX;

selfhost/cmd/w6c/main.combined.ww

@@ -776,6 +776,14 @@ def U16_MIN: u16 = 0;
 def U32_MIN: u32 = 0;
 def U64_MIN: u64 = 0;
 
+// int/uint are machine-word (Go-style, type.c:58); limits derived from
+// size(int) per #114 + user ruling; cf Go math.MaxInt; diverges from
+// Hare's per-arch literal (arch+x86_64.ha) because ww's int is 64-bit.
+def INT_MAX:  int  = (1 << (size(int)*8 - 1)) - 1;
+def INT_MIN:  int  = -1 << (size(int)*8 - 1);
+def UINT_MIN: uint = 0;
+def UINT_MAX: uint = ~(0: uint);
+
 // size is 8B on amd64; no cast needed (size ∈ unsigned class per #113).
 def SIZE_MIN: size = U64_MIN;
 def SIZE_MAX: size = U64_MAX;

selfhost/cmd/w6l/main.combined.ww

@@ -885,6 +885,14 @@ def U16_MIN: u16 = 0;
 def U32_MIN: u32 = 0;
 def U64_MIN: u64 = 0;
 
+// int/uint are machine-word (Go-style, type.c:58); limits derived from
+// size(int) per #114 + user ruling; cf Go math.MaxInt; diverges from
+// Hare's per-arch literal (arch+x86_64.ha) because ww's int is 64-bit.
+def INT_MAX:  int  = (1 << (size(int)*8 - 1)) - 1;
+def INT_MIN:  int  = -1 << (size(int)*8 - 1);
+def UINT_MIN: uint = 0;
+def UINT_MAX: uint = ~(0: uint);
+
 // size is 8B on amd64; no cast needed (size ∈ unsigned class per #113).
 def SIZE_MIN: size = U64_MIN;
 def SIZE_MAX: size = U64_MAX;

selfhost/cmd/ww/main.combined.ww

@@ -776,6 +776,14 @@ def U16_MIN: u16 = 0;
 def U32_MIN: u32 = 0;
 def U64_MIN: u64 = 0;
 
+// int/uint are machine-word (Go-style, type.c:58); limits derived from
+// size(int) per #114 + user ruling; cf Go math.MaxInt; diverges from
+// Hare's per-arch literal (arch+x86_64.ha) because ww's int is 64-bit.
+def INT_MAX:  int  = (1 << (size(int)*8 - 1)) - 1;
+def INT_MIN:  int  = -1 << (size(int)*8 - 1);
+def UINT_MIN: uint = 0;
+def UINT_MAX: uint = ~(0: uint);
+
 // size is 8B on amd64; no cast needed (size ∈ unsigned class per #113).
 def SIZE_MIN: size = U64_MIN;
 def SIZE_MAX: size = U64_MAX;

selfhost/cmd/wwdump/main.combined.ww

@@ -753,6 +753,14 @@ def U16_MIN: u16 = 0;
 def U32_MIN: u32 = 0;
 def U64_MIN: u64 = 0;
 
+// int/uint are machine-word (Go-style, type.c:58); limits derived from
+// size(int) per #114 + user ruling; cf Go math.MaxInt; diverges from
+// Hare's per-arch literal (arch+x86_64.ha) because ww's int is 64-bit.
+def INT_MAX:  int  = (1 << (size(int)*8 - 1)) - 1;
+def INT_MIN:  int  = -1 << (size(int)*8 - 1);
+def UINT_MIN: uint = 0;
+def UINT_MAX: uint = ~(0: uint);
+
 // size is 8B on amd64; no cast needed (size ∈ unsigned class per #113).
 def SIZE_MIN: size = U64_MIN;
 def SIZE_MAX: size = U64_MAX;

selfhost/test/smoke.combined.ww

@@ -753,6 +753,14 @@ def U16_MIN: u16 = 0;
 def U32_MIN: u32 = 0;
 def U64_MIN: u64 = 0;
 
+// int/uint are machine-word (Go-style, type.c:58); limits derived from
+// size(int) per #114 + user ruling; cf Go math.MaxInt; diverges from
+// Hare's per-arch literal (arch+x86_64.ha) because ww's int is 64-bit.
+def INT_MAX:  int  = (1 << (size(int)*8 - 1)) - 1;
+def INT_MIN:  int  = -1 << (size(int)*8 - 1);
+def UINT_MIN: uint = 0;
+def UINT_MAX: uint = ~(0: uint);
+
 // size is 8B on amd64; no cast needed (size ∈ unsigned class per #113).
 def SIZE_MIN: size = U64_MIN;
 def SIZE_MAX: size = U64_MAX;

test/wcc/959_types_intlim_run.c

@@ -0,0 +1,145 @@
+/*
+ * 959_types_intlim_run — runtime proof of the lib/types INT_* and UINT_*
+ * limit constants. ww's int/uint are machine-word (8B on amd64, type.c:58),
+ * so the limits are DERIVED from size(int) (Go-style, cf math.MaxInt) rather
+ * than aliased to a per-arch literal the way Hare does (arch+x86_64.ha maps
+ * INT_MAX→I32_MAX). On amd64 the derived forms must therefore equal the 64-bit
+ * limits: INT_MAX==I64_MAX, INT_MIN==I64_MIN, UINT_MAX==U64_MAX, UINT_MIN==0
+ * (#114, user ruling).
+ *
+ * Each row asserts both the value (vs the literal AND vs the i64/u64 limit
+ * const) and usability — the derived def survives const-fold, carries the
+ * right machine-word width, and is usable in arithmetic that wraps through an
+ * i32 cast (INT_MAX+43 and UINT_MAX+43 each wrap to 42 in the low 32 bits).
+ *
+ * Table-driven like 958_types_sizelim_run: each row is a self-contained ww
+ * program; the cstage `ww build -I lib` compiles it, we run the binary and
+ * assert the exit code. cstage-only by design (mirrors 951/952/957/958):
+ * per-program wwstage byte-id is the 990-997 gates' job.
+ */
+#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 *src; int want_exit; };
+
+static const struct row rows[] = {
+	/* int limits: INT_MIN is I64_MIN, INT_MAX is I64_MAX — both by
+	 * direct literal compare and against the i64 limit const. */
+	{ "package main;\n"
+	  "import types;\n"
+	  "export fn main() i32 = {\n"
+	  "	let lo: int = types.INT_MIN;\n"
+	  "	if (lo != -9223372036854775808) { return 1; };\n"
+	  "	if (lo: i64 != types.I64_MIN) { return 2; };\n"
+	  "	let hi: int = types.INT_MAX;\n"
+	  "	if (hi != 9223372036854775807) { return 3; };\n"
+	  "	if (hi: i64 != types.I64_MAX) { return 4; };\n"
+	  "	return 0;\n"
+	  "};\n", 0 },
+	/* INT_MAX usable in int arithmetic, propagated through an i32 cast:
+	 * INT_MAX + 43 wraps past INT_MIN; low 32 bits are 42. */
+	{ "package main;\n"
+	  "import types;\n"
+	  "export fn main() i32 = {\n"
+	  "	let hi: int = types.INT_MAX;\n"
+	  "	let v: int = hi + 43;\n"
+	  "	return v: i32;\n"
+	  "};\n", 42 },
+	/* uint limits: UINT_MIN is zero; UINT_MAX is U64_MAX — both by
+	 * compare and by the all-ones wrap (MAX + 1 == 0 on 8B). */
+	{ "package main;\n"
+	  "import types;\n"
+	  "export fn main() i32 = {\n"
+	  "	let lo: uint = types.UINT_MIN;\n"
+	  "	if (lo != 0) { return 1; };\n"
+	  "	let hi: uint = types.UINT_MAX;\n"
+	  "	if (hi != 18446744073709551615) { return 2; };\n"
+	  "	if (hi: u64 != types.U64_MAX) { return 3; };\n"
+	  "	if (hi + 1 != 0) { return 4; };\n"
+	  "	return 0;\n"
+	  "};\n", 0 },
+	/* UINT_MAX usable in uint arithmetic, propagated through an i32
+	 * cast: (2^64-1) + 43 wraps to 42. */
+	{ "package main;\n"
+	  "import types;\n"
+	  "export fn main() i32 = {\n"
+	  "	let hi: uint = types.UINT_MAX;\n"
+	  "	let v: uint = hi + 43;\n"
+	  "	return v: i32;\n"
+	  "};\n", 42 },
+	{ NULL, 0 }
+};
+
+int
+main(void)
+{
+	const char *bin = getenv("BIN");
+	if (!bin) bin = "out/bin";
+	char cwd[1024];
+	if (getcwd(cwd, sizeof cwd) == NULL) return 1;
+	char absbin[1024];
+	if (bin[0] != '/') {
+		snprintf(absbin, sizeof absbin, "%s/%s", cwd, bin);
+		bin = absbin;
+	}
+
+	int n = 0, fail = 0;
+	for (int i = 0; rows[i].src; i++, n++) {
+		char src[64];
+		snprintf(src, sizeof src, "/tmp/wwilim_%d_%d.ww", getpid(), i);
+
+		FILE *f = fopen(src, "wb");
+		if (f == NULL) { fail++; continue; }
+		fputs(rows[i].src, f);
+		fclose(f);
+
+		char tmpdir[64];
+		snprintf(tmpdir, sizeof tmpdir, "/tmp/wwilim_%d_d_%d", getpid(), i);
+		mkdir(tmpdir, 0755);
+
+		char cmd[2048];
+		snprintf(cmd, sizeof cmd, "cd %s && %s/ww build -I %s/lib %s",
+		    tmpdir, bin, cwd, src);
+		if (runwait(cmd) != 0) {
+			fprintf(stderr, "row %d: build failed\n  src: %s\n",
+			    i, rows[i].src);
+			fail++;
+			unlink(src); rmdir(tmpdir);
+			continue;
+		}
+
+		char outbin[128];
+		const char *base = strrchr(src, '/');
+		base = base ? base + 1 : src;
+		snprintf(outbin, sizeof outbin, "%s/%s", tmpdir, base);
+		char *dot = strrchr(outbin, '.');
+		if (dot && strcmp(dot, ".ww") == 0) *dot = '\0';
+
+		int got = runwait(outbin);
+		if (got != rows[i].want_exit) {
+			fprintf(stderr, "row %d: exit %d, want %d\n  src: %s\n",
+			    i, got, rows[i].want_exit, rows[i].src);
+			fail++;
+		}
+		unlink(src); unlink(outbin); rmdir(tmpdir);
+	}
+	if (fail) {
+		fprintf(stderr, "%d/%d types_intlim tests failed\n", fail, n);
+		return 1;
+	}
+	printf("types_intlim: %d/%d ok\n", n, n);
+	return 0;
+}