The isnan() macro defined in include/mps/types.h breaks the build on FreeBSD 14

[yurivict]

libtool: compile:  cc -DHAVE_CONFIG_H -I. -I../.. -I../../include -I../../include -D_REENTRANT -Wall -DMPS_USE_BUILTIN_COMPLEX -DNICE_DEBUG -fno-math-errno -fomit-frame-pointer -D_MPS_PRIVATE -D_THREAD_SAFE -pthread -isystem /usr/local/include -O2 -pipe -fstack-protector-strong -isystem /usr/local/include -fno-strict-aliasing -MT common/parser.lo -MD -MP -MF common/.deps/parser.Tpo -c common/parser.c  -fPIC -DPIC -o common/.libs/parser.o
In file included from common/nroots-polynomial.cpp:11:
In file included from ../../include/mps/mps.h:99:
In file included from ../../include/mps/private/system/memory-file-stream.h:50:
In file included from /usr/include/c++/v1/iostream:43:
In file included from /usr/include/c++/v1/ios:221:
In file included from /usr/include/c++/v1/__locale:18:
In file included from /usr/include/c++/v1/mutex:191:
In file included from /usr/include/c++/v1/__memory/shared_ptr.h:42:
In file included from /usr/include/c++/v1/atomic:2669:
/usr/include/c++/v1/cmath:587:17: error: expected unqualified-id
    return std::isnan(__lcpp_x);
                ^
../../include/mps/types.h:27:3: note: expanded from macro 'isnan'
  (sizeof(x) == sizeof(long double) ? isnan_ld (x) \
  ^

You assume that isnan() has to be a macro or otherwise isnan() isn't defined. But isnan() can be a function too.

Please consider using std::isnan instead.