diff options
| author | Kenta Murata <mrkn@mrkn.jp> | 2021-01-22 12:03:37 +0900 |
|---|---|---|
| committer | Kenta Murata <mrkn@mrkn.jp> | 2021-12-24 02:28:55 +0900 |
| commit | e1265c819870c6a4d6763529e9fbd2d70c722fe0 (patch) | |
| tree | f98fb219b04b9a1879032787be059aeaf8b469ab /ext | |
| parent | 8ee8ac64239626a9adea4e02ba3f0c4be4895e36 (diff) | |
[ruby/bigdecimal] Use larger precision in divide for irrational or recurring results
Just in case for irrational or recurring results, the precision of the
quotient is set to at least more than 2*Float::DIG plus alpha.
[Bug #13754] [Fix GH-94]
https://github.com/ruby/bigdecimal/commit/99442c75d3
Diffstat (limited to 'ext')
| -rw-r--r-- | ext/bigdecimal/bigdecimal.c | 13 |
1 files changed, 6 insertions, 7 deletions
diff --git a/ext/bigdecimal/bigdecimal.c b/ext/bigdecimal/bigdecimal.c index 7cec33b7c9..71499a7a19 100644 --- a/ext/bigdecimal/bigdecimal.c +++ b/ext/bigdecimal/bigdecimal.c @@ -1508,13 +1508,12 @@ BigDecimal_divide(VALUE self, VALUE r, Real **c, Real **res, Real **div) SAVE(b); *div = b; - mx = a->Prec + vabs(a->exponent); - if (mx < b->Prec + vabs(b->exponent)) mx = b->Prec + vabs(b->exponent); - mx++; /* NOTE: An additional digit is needed for the compatibility to - the version 1.2.1 and the former. */ - mx = (mx + 1) * VpBaseFig(); - GUARD_OBJ((*c), VpCreateRbObject(mx, "#0", true)); - GUARD_OBJ((*res), VpCreateRbObject((mx+1) * 2 +(VpBaseFig() + 1), "#0", true)); + mx = (a->Prec > b->Prec) ? a->Prec : b->Prec; + mx *= BASE_FIG; + if (2*BIGDECIMAL_DOUBLE_FIGURES > mx) + mx = 2*BIGDECIMAL_DOUBLE_FIGURES; + GUARD_OBJ((*c), VpCreateRbObject(mx + 2*BASE_FIG, "#0", true)); + GUARD_OBJ((*res), VpCreateRbObject(mx*2 + 2*BASE_FIG, "#0", true)); VpDivd(*c, *res, a, b); return Qnil; } |