Bug 150917

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Description of problem:
Converting a double (or a float) to unsigned long long appears to truncate the result to 32 bits (which is certainly unexpected for double since the mantissa can have more than 32 significant bits). The unexpected results are most obvious when the double or float value is negative (certainly a strange thing to convert to unsigned :-). I'd expect to see the same 64 bits in the result when I convert to unsigned long long as when I convert to long long, but the unsigned form is truncated. I'll see if I can attach the conv.c program that demos this.

Version-Release number of selected component (if applicable):
gcc version 3.4.2 20041017 (Red Hat 3.4.2-6.fc3)

How reproducible:
Always

Steps to Reproduce:
1. Compile the conv.c program with gcc -o conv -g conv.c
2. run the ./conv executable
3. see the different results for long long and unsigned long long
  

Actual Results:  llt[0] = 0xffffffffffffffd1 ullt[0] = 0x00000000ffffffd1
llt[1] = 0x0000000000000016 ullt[1] = 0x0000000000000016
llt[2] = 0xffffffffffffffd1 ullt[2] = 0x00000000ffffffd1
llt[3] = 0x0000000000000016 ullt[3] = 0x0000000000000016


Expected Results:  llt[0] = 0xffffffffffffffd1 ullt[0] = 0xffffffffffffffd1
llt[1] = 0x0000000000000016 ullt[1] = 0x0000000000000016
llt[2] = 0xffffffffffffffd1 ullt[2] = 0xffffffffffffffd1
llt[3] = 0x0000000000000016 ullt[3] = 0x0000000000000016


Additional info:

I admit this could be considered an undefined operation so any results would be valid, but getting different bits merely because I said unsigned seems awful strange (actually getting zero as a result for negative values would make more sense than what I'm seeing :-).