harec

commit a9d3768bec7024506c16493bad34b3d2c80bcc4d
parent 633f10d43ff4bcaf6720e5905f71d1392aecb136
Author: Bor Grošelj Simić <bgs@turminal.net>
Date:   Sun,  5 Feb 2023 15:51:34 +0100

lex: error out on overflowing integer exponents

References: https://todo.sr.ht/~sircmpwn/hare/737
Signed-off-by: Bor Grošelj Simić <bgs@turminal.net>

Diffstat:
M
src/lex.c
 | 
44
+++++++++++++++++++++++++++-----------------
M
tests/00-constants.ha
 | 
8
+++++++-

2 files changed, 34 insertions(+), 18 deletions(-)
diff --git a/src/lex.c b/src/lex.c
@@ -297,6 +297,25 @@ lex_name(struct lexer *lexer, struct token *out)
 	return out->token;
 }
 
+static uintmax_t
+compute_exp(uintmax_t n, int exponent, bool _signed, struct location *loc)
+{
+	if (n == 0) {
+		return 0;
+	}
+	for (int i = 0; i < exponent; i++) {
+		uintmax_t old = n;
+		n *= 10;
+		if (n / 10 != old) {
+			error(loc, "Integer literal overflow");
+		}
+	}
+	if (_signed && n > (uintmax_t)INT64_MIN) {
+		error(loc, "Integer literal overflow");
+	}
+	return n;
+}
+
 static uint32_t
 lex_literal(struct lexer *lexer, struct token *out)
 {
@@ -488,16 +507,12 @@ finalize:
 	case STORAGE_UINT:
 	case STORAGE_U64:
 	case STORAGE_SIZE:
-		out->uval = strtoumax(lexer->buf, NULL, base);
-		for (intmax_t i = 0; i < exponent; i++) {
-			out->uval *= 10;
-		}
+		out->uval = compute_exp(strtoumax(lexer->buf, NULL, base),
+				exponent, false, &out->loc);
 		break;
 	case STORAGE_ICONST:
-		out->uval = strtoumax(lexer->buf, NULL, base);
-		for (intmax_t i = 0; i < exponent; i++) {
-			out->uval *= 10;
-		}
+		out->uval = compute_exp(strtoumax(lexer->buf, NULL, base),
+				exponent, false, &out->loc);
 		if (out->uval > (uintmax_t)INT64_MAX) {
 			out->storage = STORAGE_U64;
 			break;
@@ -508,18 +523,13 @@ finalize:
 	case STORAGE_I32:
 	case STORAGE_INT:
 	case STORAGE_I64:
-		out->uval = strtoumax(lexer->buf, NULL, base);
-		for (intmax_t i = 0; i < exponent; i++) {
-			out->uval *= 10;
-		}
+		out->uval = compute_exp(strtoumax(lexer->buf, NULL, base),
+				exponent, true, &out->loc);
 		if (out->uval == (uintmax_t)INT64_MIN) {
 			// XXX: Hack
 			out->ival = INT64_MIN;
-			break;
-		}
-		out->ival = strtoimax(lexer->buf, NULL, base);
-		for (intmax_t i = 0; i < exponent; i++) {
-			out->ival *= 10;
+		} else {
+			out->ival = (intmax_t)out->uval;
 		}
 		break;
 	case STORAGE_F32:
diff --git a/tests/00-constants.ha b/tests/00-constants.ha
@@ -137,7 +137,7 @@ fn aggregates() void = {
 	u2arr as [3]u8;
 };
 
-export fn main() void = {
+fn basics() void = {
 	let i1 = 13, i2 = 13i, i3 = 13i8, i4 = 13i16, i5 = 13i32, i6 = 13i64;
 	let u1 = 13u, u2 = 13z, u3 = 13u8, u4 = 13u16, u5 = 13u32, u6 = 13u64;
 	let n1 = -13, n2 = -13u;
@@ -149,9 +149,15 @@ export fn main() void = {
 		r15 = '\U12345678';
 	let f1 = 1.0, f2 = 1f32, f3 = 1.0e2, f4 = 1.0f64;
 	let f5 = 1.23e+45, f6 = 9.87e-65, f7 = 1e-7, f8 = 5.0e-324;
+	let ie1 = 1e5i;
+
+	assert(compile("let x: u64 = 1e100;") as exited != EXIT_SUCCESS);
+};
 
+export fn main() void = {
 	// The interaction between constants and result type reduction is tested
 	// in 30-reduction.c
+	basics();
 	assignment();
 	aggregates();
 };