On 2019-09-11 7:21 a.m., Sergei Golovan wrote:
> May be. As a quick fix I can suggest a separate check for the stack
> direction in erl_bif_re.c, here's a patch.
>
> --- a/erts/emulator/beam/erl_bif_re.c
> +++ b/erts/emulator/beam/erl_bif_re.c
> @@ -90,6 +90,15 @@
> return erts_check_above_limit(&c, limit - ERTS_PCRE_STACK_MARGIN);
> }
>
> +__attribute__((noinline)) static int stack_grows_downwards(char *prev_c)
> +{
> + char c;
> + if (&c < prev_c)
> + return 1;
> + else
> + return 0;
> +}
> +
> void erts_init_bif_re(void)
> {
> char c;
> @@ -97,7 +106,7 @@
> erts_pcre_free = &erts_erts_pcre_free;
> erts_pcre_stack_malloc = &erts_erts_pcre_stack_malloc;
> erts_pcre_stack_free = &erts_erts_pcre_stack_free;
> - if ((char *) erts_ptr_id(&c) > ERTS_STACK_LIMIT)
> + if (stack_grows_downwards(&c))
> erts_pcre_stack_guard = stack_guard_downwards;
> else
> erts_pcre_stack_guard = stack_guard_upwards;
Yes. Will try tonight. Have to run.
>
> I don't think it can be accepted upstream as a permanent fix though. I
> think it'd
> be better to fix the stack limit initialization somehow.
erts_init_bif_re needs to be called after stack limit is set in thr_wrapper.
Thanks,
Dave
--
John David Anglin dave.ang...@bell.net
