Issue to compile Lenstool with gcc 10
I tried to compile Lenstool yesterday with gcc 10, and I got an issue compiling bayesChires. Due to the global variables that are defined both in the Lenstool library (o_global.c) and in bayesChires.h, I obtained duplicate symbol errors. But everything worked well with gcc 9.
I found this issue from the sextractor git, which is similar: https://github.com/astromatic/sextractor/issues/12 As they explained, it is because running gcc 10 is equivalent to running the older ones with the keyword -fno-common.
Adding the -fcommon keyword to the compiler should fix the issue (https://gcc.gnu.org/onlinedocs/gcc/Code-Gen-Options.html), or we could define all the global variables in a separate .h file instead of doing that two times.