It seems that due to recent changes in glibc, defining
_POSIX_ in a C source file that includes math.h will cause
parsing of math.h to fail. A minimal example:
printf("y = %g\n", sin(1.5));
If I compile this via
cc -Wall -lm foo.c -o foo
I get the error message
In file included from foo.c:4:
/usr/include/math.h:241: parse error before `,'
But if I delete the line #define _POSIX_, this code compiles
At a glance, I suspect that _ISOC_ on line 242 of
/usr/include/math.h is not always defined.
I'm running RH 6.0 on a Pentium with a kernel built from the
2.2.11-1 sources. glibc and glibc-devel are version 2.1.2-4
_POSIX_ is a reserved identifier by the ISO C 98