On Thu, Apr 14, 2005 at 10:35:06AM -0700, Richard Henderson wrote: > On Thu, Apr 14, 2005 at 05:27:16PM +0200, Fran?ois-Xavier Coudert wrote: > > No, since reading GFORTRAN_FPU_* variables changes the FPU mode when the > > library is loaded, while TR 15580 commands will be ran afterwards (during > > execution). > > You'll find that globally changing the rounding mode will screw up > libm functions. Which is pretty much going to make this useless. > > Further, when folks need rounding modes other than round-to-nearest, > they tend to need to switch rounding modes during the program too. > For instance, to perform the same calculation with both round-up and > round-down to get error bounds on the calculation. > > Thus I think an environment variable to do this is doubly useless.
I agree with Richard. > > All that said, C99 has <fenv.h> to control just about anything you > could want about the fpu. > Does gcc support #pragma STDC FENV_ACCESS -- Steve
