CGAL users discussion list

["Laurent Rineau (GeometryFactory)" <>]

Le Thursday 28 May 2009 12:17:37, Ben Supnik a écrit :
> when I had rounding math off (the default on OS X)

By default, the compiler optimizer assumes that the code it is compiling does 
not bother about the norm IEEE754. With most pieces of code, that is true. 
For 
the few pieces of code that need a precise conformance to IEEE754, -frounding-
math must be used.

Since g++-4.4, CGAL could probably use:
  #pragma optimize "-frounding-math"
in its code, or use the C99 FENV_ACCESS:
  #pragma STDC FENV_ACCESS ON
instead of using that command line option. That way, users would not have 
problem if they forgot that option.

-- 
Laurent Rineau, PhD
Engineer at GeometryFactory
http://www.geometryfactory.com/