exception handling complex elementary functions (fwd)

[Brian Gough]

Andrew Binkley writes:
 > Any pointers/suggestions about what I can do to get this included in the
 > main release would be appreciated.  Or if it looks ready, could you please
 > check it in.

Could you 

-- put the new functions in a separate file math_eh.c, so I don't need
to put them directly in the existing file -- it is easier for
maintenance that way.  Run the new file through indent to bring it
into line with the GNU coding conventions.

-- move the definitions in complex_math_eh.h into this file math_eh.c
(there is no need for a separate header file in this case).

-- It would be good practice to write these macros with arguments
rather than using the various variable names implicitly in the
definition.

-- The macros are not exported so they do not need a GSL_COMPLEX
prefix.  See the first definition in specfunc/error.h for an example
of how it is done in the special functions.

I'll deal with the configure script issues, such as testing whether
the floating-point exception handling functions are available.

Thanks,

-- 
Brian Gough