Re: Hexadecimal representation of a negative number

[Brian Mokrzycki]

Well I figured this out that it was likely caused by compiling guile with llvm-gcc (which is depreciated).  Please see more details on this issue in the CGEN mailing list.

Old Nabble - Sourceware - cgen list - 64-bit instruction mask emitting as signed hex value

On Oct 4, 2011, at 9:48 PM, Brian Mokrzycki wrote:

Hi all,

I'm running into a problem between Guile 1.6.4 and Guile 1.8.7.  Basically I'm manipulating bit masks in Guile and need to generate a hexadecimal string representation of an integer.  Unfortutely this worked just fine in Guile 1.6.4 but not so well in Guile 1.8.7.

The offending statement:

guile> (number->string #xFFFFFFFFFFFFFFFF 16)

Resolves to

"-1" in Guile 1.8.7
"ffffffffffffffff" in Guile 1.6.4

It appears that Guile is treating the number as a signed value in 1.8 and an unsigned value in 1.6.  I'm really looking for the 1.6 interpretation. Is this a bug?  If not, how to get this to come out as an unsigned value?

-Brian