diff options
author | naruse <naruse@b2dd03c8-39d4-4d8f-98ff-823fe69b080e> | 2010-11-09 01:57:49 +0000 |
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committer | naruse <naruse@b2dd03c8-39d4-4d8f-98ff-823fe69b080e> | 2010-11-09 01:57:49 +0000 |
commit | c383fbf93f691f443eb16761351a6943bc29d3f9 (patch) | |
tree | 538fe8e31a85eb85a67ea1d1127dee2b9dc74fba | |
parent | b3c7867df7cd186e73021f0ed9d17680999f190f (diff) |
* util.c (ruby_strtod): this code uses FPU's rounding system.
But x86's FPU calculates double precision floating-point
numbers in 80bit precision, so it fails to round the value.
So ensure the value is assigned a variable. [ruby-dev:42551]
see also [ruby-math:00802]
http://www.shudo.net/java-grandprix99/strictfp/
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@29729 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
-rw-r--r-- | ChangeLog | 9 | ||||
-rw-r--r-- | test/ruby/test_sprintf.rb | 2 | ||||
-rw-r--r-- | util.c | 7 |
3 files changed, 16 insertions, 2 deletions
@@ -1,3 +1,12 @@ +Tue Nov 9 10:44:19 2010 NARUSE, Yui <naruse@ruby-lang.org> + + * util.c (ruby_strtod): this code uses FPU's rounding system. + But x86's FPU calculates double precision floating-point + numbers in 80bit precision, so it fails to round the value. + So ensure the value is assigned a variable. [ruby-dev:42551] + see also [ruby-math:00802] + http://www.shudo.net/java-grandprix99/strictfp/ + Tue Nov 9 07:30:15 2010 Nobuyoshi Nakada <nobu@ruby-lang.org> * error.c (rb_syserr_new): new function to make SystemCallError diff --git a/test/ruby/test_sprintf.rb b/test/ruby/test_sprintf.rb index b82cbc4b90..b918ceba72 100644 --- a/test/ruby/test_sprintf.rb +++ b/test/ruby/test_sprintf.rb @@ -190,6 +190,8 @@ class TestSprintf < Test::Unit::TestCase sprintf("%20.0f", 36893488147419107329.0)) assert_equal(" Inf", sprintf("% 0e", 1.0/0.0), "moved from btest/knownbug") assert_equal(" -0.", sprintf("%#10.0f", -0.5), "[ruby-dev:42552]") + assert_equal("0x1.p+2", sprintf('%.0a', Float('0x1.fp+1')), "[ruby-dev:42551]") + assert_equal("-0x1.0p+2", sprintf('%.0a', Float('-0x1.ffp+1')), "[ruby-dev:42551]") end def test_float_hex @@ -4014,10 +4014,13 @@ ruby_hdtoa(double d, const char *xdigs, int ndigits, int *decpt, int *sign, /* Round to the desired number of digits. */ if (SIGFIGS > ndigits && ndigits > 0) { float redux = 1.0f; + volatile double d; int offset = 4 * ndigits + DBL_MAX_EXP - 4 - DBL_MANT_DIG; dexp_set(u, offset); - u.d += redux; - u.d -= redux; + d = u.d; + d += redux; + d -= redux; + u.d = d; *decpt += dexp_get(u) - offset; } |