testing that pp-numbers are parsed correctly

#define e	E
#define f	F
#define foo	FOO

123.4e+foo
123.4f+foo
12\
3.4\
e\
+\
foo
123??/
.4??/
e??/
+??/
foo
foo.123.foo.456+foo+789.foo

#if 0xfaff
0xfaff
#endif

#if 0xfe00
0xfe00
#endif

#if 0xfeff
0xfeff
#endif

.