Use Boost filesystem instead of std::fs with clang 10
This is a workaround for the fact that the clang10 build of the LCG stack was using gcc 9.2 libstdc++
, which results in a link error for debug builds when using libstdc++fs
.
See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91067 and LBCORE-1923.
/cc @chasse
Edited by Marco Clemencic