What problems may occur if the restriction(i.e. l_alloc should not fail when shrinking the block) is broken?

[孙世龙 sunshilong <sunshilong369@...>]

Hi, list

As per the documentation(i.e.
https://www.lua.org/manual/5.3/manual.html#lua_Alloc),
which says [emphasise mine]:
This code assumes that realloc does not fail when shrinking a block.
(Although Standard C does not ensure this behavior, it seems to be a
safe assumption.)

Then a question arises:
What problems may occur if the restriction(i.e. l_alloc should not
fail when shrinking the block) is broken?

Thank you for your attention to this matter.
Best regards