Issue #10676 has been reported by Martin Drst.

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Bug #10676: segmentation fault when compiling Ruby
https://bugs.ruby-lang.org/issues/10676

* Author: Martin Drst
* Status: Open
* Priority: Normal
* Assignee: 
* Category: core
* Target version: 
* ruby -v: ruby 2.2.0dev (2014-12-29 trunk 49057) [x86_64-cygwin]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN, 2.2: UNKNOWN
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When I run
   make up
I get the following error:

Updating '.':
At revision 49064.
make[1]: Entering directory '/cygdrive/c/Data/ruby-public'
./revision.h unchanged
make[1]: Leaving directory '/cygdrive/c/Data/ruby-public'
make[1]: Entering directory '/cygdrive/c/Data/ruby-public'
config.guess already exists
config.sub already exists
Downloading bundled gem files...
/cygdrive/c/Data/ruby-public/.ext/x86_64-cygwin/enc/encdb.so: [BUG] Segmentation fault
ruby 2.3.0dev (2014-12-30 trunk 49064) [x86_64-cygwin]

-- Control frame information -----------------------------------------------
c:0002 p:-3221443896 s:0004 e:000003 TOP    [FINISH]
c:0001 p:0000 s:0002 E:000540 TOP    [FINISH]


-- Other runtime information -----------------------------------------------

* Loaded script: ./ruby

* Loaded features:

    0 enumerator.so
    1 rational.so
    2 complex.so

[NOTE]
You may have encountered a bug in the Ruby interpreter or extension libraries.
Bug reports are welcome.
For details: http://www.ruby-lang.org/bugreport.html

uncommon.mk:914: recipe for target 'update-gems' failed
make[1]: *** [update-gems] Aborted (core dumped)
make[1]: Leaving directory '/cygdrive/c/Data/ruby-public'
uncommon.mk:904: recipe for target 'up' failed
make: [up] Error 2 (ignored)





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