When included, ucommon/ucommon.h (via platform.h) unexpectedly defines
NDEBUG without any warning, unless DEBUG has already been defined.
That led to a lot of head-scratching, trying to figure out why assert()
was sometimes, but not always, not doing its job while working on a
project that uses uCommon in some places.
(For the record, this was encountered in version 7.0.0, but seems to
have been present forever.)
$ cat ucommon-ndebug.cpp
#ifdef NDEBUG
#warning "NDEBUG was already defined before including <ucommon/ucommon.h>"
#endif
#include <ucommon/ucommon.h>
#ifdef NDEBUG
#error "NDEBUG is defined after including <ucommon/ucommon.h>"
#endif
$ g++ -E ucommon-ndebug.cpp >/dev/null && echo OK
ucommon-ndebug.cpp:8:2: error: #error "NDEBUG is defined after including
<ucommon/ucommon.h>"
#error "NDEBUG is defined after including <ucommon/ucommon.h>"
^~~~~
$ g++ -E -DDEBUG ucommon-ndebug.cpp >/dev/null && echo OK
OK
