The current gcc initializer code is too permissive, AFAICS - [0][0] 1 will be rejected by gcc too, so we shouldn't consider it "broken gcc syntax". There was another bug in there - *ep = NULL; token = initializer(ep, token); if (!expr) break; add_expression(list, expr); would not catch the case when we have e.g. .foo = <bad expression> and we end up with list polluted by EXPR_IDENTIFIER with NULL ->ident_expression. Should be if (!*ep) instead. This also cleans it up by splitting the list handling case up from the loop, and making the single initializer parsing a function of its own.