CommonULong64 OverflowException

I've been working on this as well and have been having the same issues as you have. Any time a conversion from your -176378626 to a unsigned integer is causing an overflow. -176378626 should equate to 4118588670 as a unsigned 32 bit value but it seems however I try, I can't get VB to do that conversion. C handle it fine with it's dynamic casting, but for some reason VB keeps overflowing.

I'll keep pounding, but for the life of me I can't get VB do do the conversion. For reference, This is what should be the true values

high = 4, low = -176378626 (4118588670)

val = (high << 32) | low

high << 32 -> 0x0000000400000000

low -> 0x00000000F57CACFE

value64 -> 0x00000004F57CACFE

value64 -> 18446744073533172990

Just as an aside, you cannot convert -1 into a unsigned number it seems:

Dim ui64 As UInt32 = Convert.ToUInt32(-1)

The value should be 4294967295 but it results in an overflow exception.

If anyone out there understands the insides of VB's type system enough to make sense out of this, if you would please chime in, we'd really appreciate it.

Any chance on writing the method that does the conversion in C?

-Joe