I was looking at a bug on ksh93 that is "core dumps doing glob pattern on long string" and it happen that bash suffer the same.
$ [[ $(printf '%0100000d' 0) == +(0) ]] I see 3 way of fixing this 1) [[ string == pattern ]] is for glob pattern, so string should be limited to PATH_MAX, so an upfront string length on string could prevent to call the glob pattern recursive functions, and then avoid the core dump. 2) Since some may have abused the glob pattern with long string bigger then PATH_MAX but smaller than core dump, imposing a PATH_MAX limit may break some wrong scripts, so instead we could have a fix recursion deep level, as we do have for shell functions calling, this hopefully should allow wrong doing script with abused string length to continue to run, yet avoiding core dump when reaching the limit, i.e break the call path. 3) Implement a stack deep check in the recursion, when getting close to the end of stack break the function trail (like function too deep for recursive functions). A last possibility is 'do nothing', since most of the people/scripts that works, don't care. Yet, the core dump limit is not the same on between bash and ksh93 then making porting hazardous. If the bash team plan to fix it, I'd like to know which way, so we could make ksh93 behave the same, for 1) and 2) it would be the exact same limit, for 3) it would be depending on stack usage, would not be the same exact string length that would break, but it would breaks instead of core dumping. Cheers,
