Bug#777473: A good lead and a workaround

[Julien Puydt]

Hi,

it is now upstream's bug:
https://sourceforge.net/p/ecls/bug/305

after some discussion on the sage-devel mailing-list, it was found that 
the problem is related to gmp 5.1.3 vs gmp 6.0.0.

I also notice that if I force ECL_OPT_SET_GMP_MEMORY_FUNCTIONS to 0 in 
src/c/main.d, then the crash disappears : it's a workaround.

Snark on #debian-science