A breaking change was introduced in boost 1.56 : the implicit conversion to bool was removed. Instead, an explicit operator bool was provided. The getters were also changed, so we cannot use them and retain compatibility with older boost versions.
By putting the would-be boolean expression in a conditional, we now invoke the explicit operator bool (also known as contextual conversion to bool) for boost >= 1.56 and the implicit conversion to bool for < 1.56.
4a9aa74 Savannah #43198. Work around boost 1.56+ incompatibility.
libcore/DragState.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)