Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
To use Boost instead of the standard library, we must use the cmake option -D BOOST=ON Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
This commit allows us to build Lean without the pthread dependency. It is also useful if we want to implement multi-threading on top of Boost. Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>