fix: fix off-by-one for leading zeroes

Author: wooster0

src/translate_c.zig

@@ -5647,7 +5647,7 @@ fn parseCNumLit(c: *Context, m: *MacroCtx) ParseError!Node {
     switch (m.list[m.i].id) {
         .IntegerLiteral => |suffix| {
             var radix: []const u8 = "decimal";
-            if (lit_bytes.len > 2 and lit_bytes[0] == '0') {
+            if (lit_bytes.len >= 2 and lit_bytes[0] == '0') {
                 switch (lit_bytes[1]) {
                     '0'...'7' => {
                         // Octal

test/translate_c.zig

@@ -3842,4 +3842,16 @@ pub fn addCases(cases: *tests.TranslateCContext) void {
     , &[_][]const u8{
         \\pub const FOO = "";
     });
+
+    cases.add("leading zeroes",
+        \\#define O_RDONLY  00
+        \\#define HELLO 000
+        \\#define ZERO 0
+        \\#define WORLD 00000123
+    , &[_][]const u8{
+        \\pub const O_RDONLY = @as(c_int, 0o0);
+        \\pub const HELLO = @as(c_int, 0o00);
+        \\pub const ZERO = @as(c_int, 0);
+        \\pub const WORLD = @as(c_int, 0o0000123);
+    });
 }