Fix GCC 10 linker error

[ghost]

gcc-10 and above flipped to a default from -fcommon to -fno-common which generates a linker error. https://gcc.gnu.org/gcc-10/changes.html https://gcc.gnu.org/gcc-10/porting_to.html

[spth]

Thanks for spotting this issue and proposing a fix.

However, since each line array is used only in a single function, IMO, the cleaner solution would be to just use local arrays instead.

[spth]

I have implemented the solution using local arrays instead of renaming the global ones.