bootstrap/7143: real.c: In function `make_nan': `TFbignan' undeclared

[Neil Booth]

I've got a clue.  You mentioned you were compiling with -pedantic.

Is DEC a built-in?  If so, -pedantic won't define it because it's in
the user's namespace.  If DEC is defined in a file, then it doesn't
matter of course.

We didn't used to get this stuff right, but if your target has been
converted to the new CPP builtins recently then we've suddenly
started getting it right and it's prevented your bootstrap.

Maybe real.c should not be -pedantic, or should check for __DEC__
too (assuming that's defined).

Neil.