The branch master has been updated
       via  ce84456ddf4e57c18a84858755b8b90c183a270e (commit)
      from  c828cd7cd0426dde10b07e7b68f3741a5ea91fc6 (commit)


- Log -----------------------------------------------------------------
commit ce84456ddf4e57c18a84858755b8b90c183a270e
Author: Richard Levitte <[email protected]>
Date:   Sat Mar 26 00:07:50 2016 +0100

    Math::BigInt does floored divs, BN_div does truncated div, compensate
    
    According to documentation, perl's Math::BigInt does floored division,
    i.e. the bdiv function does 1 / -4 = -1.  OpenSSL's BN_div, as well as
    bc, do truncated division, i.e. 1 / -4 = 0.
    
    We need to compensate for that difference in test/recipes/bc.pl to
    make sure to verify the bntest results under its own conditions, by
    dividing the absolute values of the given numbers and fixup the
    result's negativity afterwards.
    
    Closes RT#4485
    
    Reviewed-by: Viktor Dukhovni <[email protected]>

-----------------------------------------------------------------------

Summary of changes:
 test/recipes/bc.pl | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/test/recipes/bc.pl b/test/recipes/bc.pl
index 29a4a8a..f7d4dc6 100644
--- a/test/recipes/bc.pl
+++ b/test/recipes/bc.pl
@@ -46,7 +46,16 @@ sub __multiplier {
        if ($operator eq "*") {
            $operand1->bmul($operand2);
        } elsif ($operator eq "/") {
+           # Math::BigInt->bdiv() is documented to do floored division,
+           # i.e. 1 / -4 = -1, while bc and OpenSSL BN_div do truncated
+           # division, i.e. 1 / -4 = 0.  We need to make the operation
+           # work like OpenSSL's BN_div to be able to verify.
+           my $neg = ($operand1->is_neg()
+                      ? !$operand2->is_neg() : $operand2->is_neg());
+           $operand1->babs();
+           $operand2->babs();
            $operand1->bdiv($operand2);
+           if ($neg) { $operand1->bneg(); }
        } elsif ($operator eq "%") {
            # Here's a bit of a quirk...
            # With OpenSSL's BN, as well as bc, the result of -10 % 3 is -1
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