Does C support G_ and H_ floating point arithmetic?

[Tho Tran]

Is is true that the C compiler on the VAX does not support all floating
point data types provided by the VAX macro assembler?  

If you look at what is available on the VAX macro assembler, there are four 
groups of floating point instructions, one for each floating point data 
type: F_floating, D_floating, G_floating, and H_floating.  F_floating
is of float and D_floating of double.

For instance, when you have a program as listed below, variables a and b 
are treated as D_float; which is clearly shown if you compile with the -S
option that generates assembler code.

      main () {

         double a, b;
            
         a=1;
         b=1;
         
         a = a +b;
      
      } 

Can anyone tell me how to force the C compiler to use the G_float or H_float?
Please respond by E-mail to:
    tho%swevax.uconn.csnet at csnet-relay

thanks
-tho