Compiler doesn't warn about pinter referencing array past it's lifetime

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1

I’m a bit confused about this scenario: Shouldn’t the compiler or even the LSP warn about a line like const fields = fields_array[0..index]; since the lifetime of fields_array ends with the function, as shown below?

I don’t have experience with manual memory management, so trying to stay alert.

const HttpMessage = struct {
    start_line: [] const u8,
    fields: [][] const u8,
    message: ?[] const u8,

    pub fn init(buf: []const u8) HttpMessage {

            var tokenizer = std.mem.tokenizeSequence(u8, buf,"\r\n");
            const start_line = tokenizer.next().?;
            var fields_array: [30][]const u8 = undefined;
            var index: u32 = 0;
            while(tokenizer.next()) |header|: (index += 1) {
                if (header.len == 0) {
                    break;
                }
                fields_array[index] = header[0..];
            }
            const fields = fields_array[0..index];
            var message: ?[] const u8 = undefined;
            if (tokenizer.next()) |text| {
                message = text;
            } else {
                message = null;
            }
            return HttpMessage{
                .start_line = start_line,
                .fields = fields[0..],
                .message = message,
            };
    }
};
2

There’s been some discussion on this recently here.

I haven’t read through that in a while, but I do believe the core team has some plan to address cases where possible.

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