g++ bug with double function result in <= expression?

[Jonathan Knispel]

  This looks a bit like a compiler bug to me, but I may be missing something
obvious.  :-)

  The code's below.  "a" and "b" are a pair of structs with identical
values, but "a.toReal() <= b.toReal()" returns true if toReal() is defined
with a float return value (expected) and false if defined with a double
return value (huh?).  If I assign the results of the calls to a pair of
appropriately typed variables and test the variables with <=, the problem
goes away (workaround).

  Here's the sample output from a couple of runs:

Using double
a < b false
a <= b false
ad < bd false
ad <= bd true

Using float
a < b false
a <= b true
ad < bd false
ad <= bd true

  I've tried with g++ 3.2.2 (i386-redhat-linux), 3.3.3 (i586-suse-linux) and
3.4.2 (i686-pc-linux-gnu).  Stepping through in gdb, the values all look
fine, but the <= test for the function calls fails.  Any ideas?

Thanks in advance,
                                                           Jonathan

#include <sys/time.h>
#include <iostream>

using std::cout;

#if 1

typedef double RealType;
const char* realTypeName = "double";

#else

typedef float RealType;
const char* realTypeName = "float";

#endif

struct TimeVal : public timeval
{
    TimeVal(RealType t) {
        tv_sec = static_cast<unsigned int>(t);
        tv_usec = static_cast<unsigned int>(t - (t - tv_sec));
    }

    RealType toReal() { return tv_sec + 0.0000001 * tv_usec; }
};

int
main(int argc,
     char** argv)
{
    cout << "Using " << realTypeName << '\n';

    TimeVal a(2.1);
    TimeVal b(2.1);

    if (a.toReal() < b.toReal())
        cout << "a < b true\n";
    else
        cout << "a < b false\n";

    if (a.toReal() <= b.toReal())
        cout << "a <= b true\n";
    else
        cout << "a <= b false\n";

    RealType ad = a.toReal();
    RealType bd = b.toReal();

    if (ad < bd)
        cout << "ad < bd true\n";
    else
        cout << "ad < bd false\n";

    if (ad <= bd)
        cout << "ad <= bd true\n";
    else
        cout << "ad <= bd false\n";
}