MAX_SIG_SIZE limitation

[Henriojord]

If you set the MAX_SIG_SIZE value upper than 1015, the program crashes with a segmentation fault.

[andreasjansson]

@Henriojord Huh, nice find! I'll have a look if I see something obvious, or at least put a warning in the code.

[Henriojord]

I'm not sure, but the bug seems to come from the variable "Delta", in "russel" function.

[tnaumann]

This appears to be a limitation of emd.c. Several arrays are created of length MAX_SIG_SIZE1 which are managed by the stack and consequently large values of MAX_SIG_SIZE can cause a seg fault.

You may be able to get around this by changing the default stack size allocation (e.g. via /etc/security/limits.conf) before compiling, but a better solution probably involves rewriting the file in order to allocate space via malloc. NB: Some things (e.g. MATLAB's mex) may not respect this value anyway.

@Henriojord I suspect that if things failed in russel it was because either D[MAX_SIG_SIZE1] and S[MAX_SIG_SIZE1] created in init were not able to be properly passed (causing a seg fault on the opening brace) or there wasn't enough space for one of the variable initializations in russel (e.g. causing a seg fault on Delta[MAX_SIG_SIZE1][MAX_SIG_SIZE1]).