Forum: Ruby-core [ruby-trunk - Bug #7352][Assigned] Array#bsearch test failure on Range (32bits MinGW)

Issue #7352 has been reported by luislavena (Luis Lavena).

----------------------------------------
Bug #7352: Array#bsearch test failure on Range (32bits MinGW)
https://bugs.ruby-lang.org/issues/7352

Author: luislavena (Luis Lavena)
Status: Assigned
Priority: Normal
Assignee: mame (Yusuke Endoh)
Category: test
Target version: 2.0.0
ruby -v: ruby 2.0.0dev (2012-11-15 trunk 37656) [i386-mingw32]


=begin
Hello,

After r37655, I noticed a failing test on RubyInstaller CI for x86:

 test_bsearch_for_float(TestRange) 
[C:/Users/Luis/Code/ruby/ruby/test/ruby/test_range.rb:392]:
 Expected -1.7976931348623157e+308 to be >= NaN.

This do not fail on x64, both running with GCC 4.7.2

I don't have Linux test results to compare at this time, but wanted to 
raise awareness of this issue.

Thank you
=end

Issue #7352 has been updated by mame (Yusuke Endoh).


Thank you Luis, I'll try it on windows.

--
Yusuke Endoh <mame@tsg.ne.jp>
----------------------------------------
Bug #7352: Array#bsearch test failure on Range (32bits MinGW)
https://bugs.ruby-lang.org/issues/7352#change-32911

Author: luislavena (Luis Lavena)
Status: Assigned
Priority: Normal
Assignee: mame (Yusuke Endoh)
Category: test
Target version: 2.0.0
ruby -v: ruby 2.0.0dev (2012-11-15 trunk 37656) [i386-mingw32]


=begin
Hello,

After r37655, I noticed a failing test on RubyInstaller CI for x86:

 test_bsearch_for_float(TestRange) 
[C:/Users/Luis/Code/ruby/ruby/test/ruby/test_range.rb:392]:
 Expected -1.7976931348623157e+308 to be >= NaN.

This do not fail on x64, both running with GCC 4.7.2

I don't have Linux test results to compare at this time, but wanted to 
raise awareness of this issue.

Thank you
=end

Issue #7352 has been updated by phasis68 (Heesob Park).


I guess this bug is related with the optimization of GCC 4.7.2.
The version built with VC 2010 or GCC 4.5.2 works fine.
The workaround is adding a volatile qualifier.

Additionally, I found some problems in Range#bsearch method.

1. The following example in documentation is wrong.
      (0..4).bsearch {|i| 100 - i } #=> 1, 2 or 3
      (0..4).bsearch {|i| 300 - i } #=> nil
      (0..4).bsearch {|i|  50 - i } #=> nil

2. (0.0...Float::INFINITY).bsearch {|x| Math.log(x) >= 0 } returns nil 
instead of 1.0 on Windows.

3. (0.0..10).bsearch {|x| 7.0-x} returns nil instead of 7.0

Here is a patch for all above problems:

diff --git a/range.c b/range.c.new
index 7d30383..0e0fd14 100644
--- a/range.c
+++ b/range.c.new
@@ -513,9 +513,9 @@ range_step(int argc, VALUE *argv, VALUE range)
  *  satisfies the condition, it returns nil.
  *
  *     ary = [0, 100, 100, 100, 200]
- *     (0..4).bsearch {|i| 100 - i } #=> 1, 2 or 3
- *     (0..4).bsearch {|i| 300 - i } #=> nil
- *     (0..4).bsearch {|i|  50 - i } #=> nil
+ *     (0..4).bsearch {|i| 100 - ary[i] } #=> 1, 2 or 3
+ *     (0..4).bsearch {|i| 300 - ary[i] } #=> nil
+ *     (0..4).bsearch {|i|  50 - ary[i] } #=> nil
  *
  *  You must not mix the two modes at a time; the block must always
  *  return either true/false, or always return a number.  It is
@@ -543,10 +543,10 @@ range_bsearch(VALUE range)
       smaller = 0; \
   } \
   else if (rb_obj_is_kind_of(v, rb_cNumeric)) { \
-      switch (rb_cmpint(rb_funcall(v, id_cmp, 1, INT2FIX(0)), v, 
INT2FIX(0)) < 0) { \
+      switch (rb_cmpint(rb_funcall(v, id_cmp, 1, INT2FIX(0)), v, 
INT2FIX(0))) { \
     case 0: return val; \
-    case 1: smaller = 1; \
-    case -1: smaller = 0; \
+    case -1: smaller = 1; break; \
+    case 1: smaller = 0; \
       } \
   } \
   else { \
@@ -586,6 +586,7 @@ range_bsearch(VALUE range)
   double high = RFLOAT_VALUE(rb_Float(end));
   double mid, org_high;
   int count;
+  org_high = high;
 #ifdef FLT_RADIX
 #ifdef DBL_MANT_DIG
 #define BSEARCH_MAXCOUNT (((FLT_RADIX) - 1) * (DBL_MANT_DIG + 
DBL_MAX_EXP) + 100)
@@ -646,7 +647,7 @@ range_bsearch(VALUE range)
   }
   if (isinf(low) && low < 0) {
       /* the range is (-INFINITY..high) */
-      double nlow = -1.0, dec;
+      volatile double nlow = -1.0, dec;
       if (nlow > high) nlow = high;
       count = BSEARCH_MAXCOUNT;
       /* find lower bound by checking low, low*2, low*4, ... */
@@ -697,7 +698,6 @@ range_bsearch(VALUE range)
     binsearch:
   /* find the desired value within low..high */
   /* where low is not -INFINITY and high is not INFINITY */
-  org_high = high;
   count = BSEARCH_MAXCOUNT;
   while (low < high && count >= 0) {
       mid = low + ((high - low) / 2);
----------------------------------------
Bug #7352: Array#bsearch test failure on Range (32bits MinGW)
https://bugs.ruby-lang.org/issues/7352#change-32921

Author: luislavena (Luis Lavena)
Status: Assigned
Priority: Normal
Assignee: mame (Yusuke Endoh)
Category: test
Target version: 2.0.0
ruby -v: ruby 2.0.0dev (2012-11-15 trunk 37656) [i386-mingw32]


=begin
Hello,

After r37655, I noticed a failing test on RubyInstaller CI for x86:

 test_bsearch_for_float(TestRange) 
[C:/Users/Luis/Code/ruby/ruby/test/ruby/test_range.rb:392]:
 Expected -1.7976931348623157e+308 to be >= NaN.

This do not fail on x64, both running with GCC 4.7.2

I don't have Linux test results to compare at this time, but wanted to 
raise awareness of this issue.

Thank you
=end

Issue #7352 has been updated by mame (Yusuke Endoh).


phasis68 (Heesob Park) wrote:
> I guess this bug is related with the optimization of GCC 4.7.2.
> The version built with VC 2010 or GCC 4.5.2 works fine.
> The workaround is adding a volatile qualifier.
>
> Additionally, I found some problems in Range#bsearch method.

I've committed your patch, my MEGA thanks!

I would really like you to have a commit bit.  Are you willing?

Matz, what do you thing?  He is a great all-round player; his
contribution to Ruby includes deadlock issues (his patches was
applied by kosaki), windows issues (accepted by usa and naruse),
algorithmic issue (accepted by mrkn and me), documentation
issues (by nobu), etc.

  $ grep -i heesob ChangeLog doc/ChangeLog-* | wc -l
  18

--
Yusuke Endoh <mame@tsg.ne.jp>
----------------------------------------
Bug #7352: Array#bsearch test failure on Range (32bits MinGW)
https://bugs.ruby-lang.org/issues/7352#change-32931

Author: luislavena (Luis Lavena)
Status: Closed
Priority: Normal
Assignee: mame (Yusuke Endoh)
Category: test
Target version: 2.0.0
ruby -v: ruby 2.0.0dev (2012-11-15 trunk 37656) [i386-mingw32]


=begin
Hello,

After r37655, I noticed a failing test on RubyInstaller CI for x86:

 test_bsearch_for_float(TestRange) 
[C:/Users/Luis/Code/ruby/ruby/test/ruby/test_range.rb:392]:
 Expected -1.7976931348623157e+308 to be >= NaN.

This do not fail on x64, both running with GCC 4.7.2

I don't have Linux test results to compare at this time, but wanted to 
raise awareness of this issue.

Thank you
=end

Issue #7352 has been updated by phasis68 (Heesob Park).


Thanks, but I don't want to have a commit bit.

I am content with a tester and debugger.
----------------------------------------
Bug #7352: Array#bsearch test failure on Range (32bits MinGW)
https://bugs.ruby-lang.org/issues/7352#change-32932

Author: luislavena (Luis Lavena)
Status: Closed
Priority: Normal
Assignee: mame (Yusuke Endoh)
Category: test
Target version: 2.0.0
ruby -v: ruby 2.0.0dev (2012-11-15 trunk 37656) [i386-mingw32]


=begin
Hello,

After r37655, I noticed a failing test on RubyInstaller CI for x86:

 test_bsearch_for_float(TestRange) 
[C:/Users/Luis/Code/ruby/ruby/test/ruby/test_range.rb:392]:
 Expected -1.7976931348623157e+308 to be >= NaN.

This do not fail on x64, both running with GCC 4.7.2

I don't have Linux test results to compare at this time, but wanted to 
raise awareness of this issue.

Thank you
=end

Issue #7352 has been updated by mame (Yusuke Endoh).


Okay.  Tell me if you change your mind!

--
Yusuke Endoh <mame@tsg.ne.jp>
----------------------------------------
Bug #7352: Array#bsearch test failure on Range (32bits MinGW)
https://bugs.ruby-lang.org/issues/7352#change-32943

Author: luislavena (Luis Lavena)
Status: Closed
Priority: Normal
Assignee: mame (Yusuke Endoh)
Category: test
Target version: 2.0.0
ruby -v: ruby 2.0.0dev (2012-11-15 trunk 37656) [i386-mingw32]


=begin
Hello,

After r37655, I noticed a failing test on RubyInstaller CI for x86:

 test_bsearch_for_float(TestRange) 
[C:/Users/Luis/Code/ruby/ruby/test/ruby/test_range.rb:392]:
 Expected -1.7976931348623157e+308 to be >= NaN.

This do not fail on x64, both running with GCC 4.7.2

I don't have Linux test results to compare at this time, but wanted to 
raise awareness of this issue.

Thank you
=end