On current master:
 0  CXX      support/libbitcoin_util_a-lockedpool.o
 1support/lockedpool.cpp: In member function ‘void Arena::free(void*)’:
 2support/lockedpool.cpp:99:20: error: ‘runtime_error’ is not a member of ‘std’
 3   99 |         throw std::runtime_error("Arena: invalid or double free");
 4      |                    ^~~~~~~~~~~~~
 5support/lockedpool.cpp:22:1: note: ‘std::runtime_error’ is defined in header ‘<stdexcept>’; did you forget to ‘#include <stdexcept>’?
 6   21 | #include <algorithm>
 7  +++ |+#include <stdexcept>
 8   22 | #ifdef ARENA_DEBUG
 9support/lockedpool.cpp: In member function ‘void LockedPool::free(void*)’:
10support/lockedpool.cpp:320:16: error: ‘runtime_error’ is not a member of ‘std’
11  320 |     throw std::runtime_error("LockedPool: invalid address not pointing to any arena");
12      |                ^~~~~~~~~~~~~
13support/lockedpool.cpp:320:16: note: ‘std::runtime_error’ is defined in header ‘<stdexcept>’; did you forget to ‘#include <stdexcept>’?