wcc: reject final-band integer overflow; restore rewind columns

lib/ww/syntax/lex.ww

@@ -269,6 +269,9 @@ fn skipws(l: *lex) bool = {
 
 fn parseint(p: *u8, n: u64, base: i32, ok: *bool) u64 = {
 	let v: u64 = 0u64;
+	let b: u64 = base: u64;
+	let cutoff: u64 = ~0u64 / b;
+	let cutlim: u64 = ~0u64 % b;
 	let got: bool = false;
 	let i: u64 = 0u64;
 	for (i < n) {
@@ -294,8 +297,11 @@ fn parseint(p: *u8, n: u64, base: i32, ok: *bool) u64 = {
 		};
 		if (d < 0) { *ok = false; return 0u64; };
 		if (d >= base) { *ok = false; return 0u64; };
-		if (v > ~0u64 / (base: u64)) { *ok = false; return 0u64; };
-		v = v * (base: u64) + (d: u64);
+		if (v > cutoff || (v == cutoff && (d: u64) > cutlim)) {
+			*ok = false;
+			return 0u64;
+		};
+		v = v * b + (d: u64);
 		got = true;
 		i += 1u64;
 	};
@@ -551,6 +557,7 @@ fn lexnum(l: *lex, start: *pos, out: *tok) void = {
 	if (pc >= 0) {
 		if (isidstart(pc: rune)) {
 			let sb: u64 = l.lpos;
+			let sc: i32 = l.col;
 			for (true) {
 				let cc: i32 = lpeek(l, 0u64);
 				if (cc < 0) { break; };
@@ -591,6 +598,7 @@ fn lexnum(l: *lex, start: *pos, out: *tok) void = {
 				out.tsuffix = strings.dup(view);
 			} else {
 				l.lpos = sb;
+				l.col = sc;
 			};
 		};
 	};

lib/ww/syntax/tok_test.ww

@@ -309,3 +309,32 @@ fn checkfloat(src: str, want: u64) void = {
 	checkfloat("1.0e308", 0x7FE1CCF385EBC8A0u64);
 	checkfloat("2.225073858507202e-308", 0x0010000000000001u64);
 };
+
+@test fn intfinalband() void = {
+	let src: str = "18446744073709551616";
+	let l: lex;
+	lexinit(&l, "t", src.ptr, src.len: u64);
+	let t: tok;
+	lexnext(&l, &t);
+	assert(!(t.kind != tkind.TK_ERR));
+	assert(!(l.errs != 1));
+};
+
+@test fn suffixrewindcols() void = {
+	let src: str = "1foo bar";
+	let l: lex;
+	lexinit(&l, "t", src.ptr, src.len: u64);
+	let t: tok;
+	lexnext(&l, &t);
+	assert(!(t.kind != tkind.TK_INT));
+	assert(!(t.col != 1));
+	assert(!(t.uval != 1u64));
+	lexnext(&l, &t);
+	assert(!(t.kind != tkind.TK_IDENT));
+	assert(!(t.col != 2));
+	assert(!(t.text != "foo"));
+	lexnext(&l, &t);
+	assert(!(t.kind != tkind.TK_IDENT));
+	assert(!(t.col != 6));
+	assert(!(t.text != "bar"));
+};