Re: More test results...

[Benjamin Kosnik <bkoz at redhat dot com>]

> No, but the patch under discussion changes several static data members to
> be inherited, so the mangled name is different.  If the default is wrong
> for a type, it must be overridden in the (derived) specialization, so the
> mangled name depends on whether or not the default is correct.

Hmm. Well, numeric_limits only has meaning as a specialization. For the
required specializations, no derivation is required. It stands to reason
that non-required, user-defined specializations would also not be
derivations. So, I'm not quite sure what you are getting at with this
particular argument. 

The idea that now __numeric_limits_base* is in the exported symbols list 
is the bit that personally makes me nervous. I thought this was the part 
that you were nervous about.

Here, try this:

#include <limits>

class B { };

namespace std
{
  template<>
    struct numeric_limits<B>
    {
    public:
      static const bool is_specialized = false;
      static B min() throw();
      static B max() throw();
      
      static const int  digits = 0;
      static const int  digits10 = 0;
      static const bool is_signed = false;
      static const bool is_integer = false;
      static const bool is_exact = false;
      static const int  radix = 0;
      static B epsilon() throw();
      static B round_error() throw();
  
      static const int  min_exponent = 0;
      static const int  min_exponent10 = 0;
      static const int  max_exponent = 0;
      static const int  max_exponent10 = 0;
  
      static const bool has_infinity = false;
      static const bool has_quiet_NaN = false;
      static const bool has_signaling_NaN = false;
      static const float_denorm_style has_denorm = denorm_absent;
      static const bool has_denorm_loss = false;
      static B infinity() throw();
      static B quiet_NaN() throw();
      static B signaling_NaN() throw();
      static B denorm_min() throw();
  
      static const bool is_iec559 = false;
      static const bool is_bounded = false;
      static const bool is_modulo = false;
  
      static const bool traps = false;
      static const bool tinyness_before = false;
      static const float_round_style round_style = round_toward_zero;
    };

  const bool numeric_limits<B>::is_specialized;
  const int  numeric_limits<B>::digits;
  const int  numeric_limits<B>::digits10;
  const bool numeric_limits<B>::is_signed;
  const bool numeric_limits<B>::is_integer;
  const bool numeric_limits<B>::is_exact;
  const int  numeric_limits<B>::radix;
  const int  numeric_limits<B>::min_exponent;
  const int  numeric_limits<B>::min_exponent10;
  const int  numeric_limits<B>::max_exponent;
  const int  numeric_limits<B>::max_exponent10;
  const bool numeric_limits<B>::has_infinity;
  const bool numeric_limits<B>::has_quiet_NaN;
  const bool numeric_limits<B>::has_signaling_NaN;
  const float_denorm_style numeric_limits<B>::has_denorm;
  const bool numeric_limits<B>::has_denorm_loss;
  const bool numeric_limits<B>::is_iec559;
  const bool numeric_limits<B>::is_bounded;
  const bool numeric_limits<B>::is_modulo;
  const bool numeric_limits<B>::traps;
  const bool numeric_limits<B>::tinyness_before;
  const float_round_style numeric_limits<B>::round_style;
}

int main()
{ 
  bool b = std::numeric_limits<B>::has_denorm_loss;
  
  return 0;
}

%nm a.out | grep numeric_limits
080a3084 B _ZNSt14numeric_limitsI1BE10has_denormE
080a308a B _ZNSt14numeric_limitsI1BE10is_boundedE
080a3069 B _ZNSt14numeric_limitsI1BE10is_integerE
080a3090 B _ZNSt14numeric_limitsI1BE11round_styleE
080a3080 B _ZNSt14numeric_limitsI1BE12has_infinityE
080a3078 B _ZNSt14numeric_limitsI1BE12max_exponentE
080a3070 B _ZNSt14numeric_limitsI1BE12min_exponentE
080a3081 B _ZNSt14numeric_limitsI1BE13has_quiet_NaNE
080a305c B _ZNSt14numeric_limitsI1BE14is_specializedE
080a307c B _ZNSt14numeric_limitsI1BE14max_exponent10E
080a3074 B _ZNSt14numeric_limitsI1BE14min_exponent10E
080a3088 B _ZNSt14numeric_limitsI1BE15has_denorm_lossE
080a308d B _ZNSt14numeric_limitsI1BE15tinyness_beforeE
080a3082 B _ZNSt14numeric_limitsI1BE17has_signaling_NaNE
080a306c B _ZNSt14numeric_limitsI1BE5radixE
080a308c B _ZNSt14numeric_limitsI1BE5trapsE
080a3060 B _ZNSt14numeric_limitsI1BE6digitsE
080a3064 B _ZNSt14numeric_limitsI1BE8digits10E
080a306a B _ZNSt14numeric_limitsI1BE8is_exactE
080a3089 B _ZNSt14numeric_limitsI1BE9is_iec559E
080a308b B _ZNSt14numeric_limitsI1BE9is_moduloE
080a3068 B _ZNSt14numeric_limitsI1BE9is_signedE

-benjamin