From fe8ecb298f35fad43fc323af89f1232a1aee4c87 Mon Sep 17 00:00:00 2001
From: 1820893135-pixel <1820893135@qq.com>
Date: Wed, 23 Sep 2026 17:45:14 +0800
Subject: [PATCH] Report an error instead of asserting when the token stream
 ends early (closes #386)

next() advanced the token pointer and, on reaching the end of the token
stream, hit assert(0) before the switch that handles exactly that case:

    if (P->token == P->te) {
        --P->token;
        assert(0);
        switch (P->token->id) {
        case LEX_TOK_EOS: case LEX_TOK_EOB: case LEX_TOK_EOF:
            P->token->id = LEX_TOK_EOF;
            return P->token;
        }
        error_tok(P, P->token, "unexpected end of input");
    }

The switch below the assert already produces a context-specific syntax
error for an exhausted token stream, so the assert only turned those cases
into an abort.  It looks like a stray debug assert left in during
development.  A schema with an embedded NUL reaches this branch:

    schema.fbs: root_type\0DoubleVec;
    $ flatcc_d schema.fbs
    flatcc_d: parser.c:357: next: Assertion `0' failed.
    Aborted (core dumped)

Removing it lets the existing handling run, and the same schema now fails
with a normal error and exit status 255:

    schema.fbs:5:10: error: '': missing ';' expected by root_type
---
 src/compiler/parser.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/src/compiler/parser.c b/src/compiler/parser.c
index b179be567..45b5c9da2 100644
--- a/src/compiler/parser.c
+++ b/src/compiler/parser.c
@@ -354,7 +354,6 @@ static fb_token_t *next(fb_parser_t *P)
     if (P->token == P->te) {
         /* We keep returning end of token to help binary operators etc., if any. */
         --P->token;
-        assert(0);
         switch (P->token->id) {
         case LEX_TOK_EOS: case LEX_TOK_EOB: case LEX_TOK_EOF:
             P->token->id = LEX_TOK_EOF;