Issue #6119 has been reported by Luis Lavena.

----------------------------------------
Bug #6119: Usage of CPPFLAGS during configure result in duplicated values for RbConfig CPPFLAGS information
https://bugs.ruby-lang.org/issues/6119

Author: Luis Lavena
Status: Open
Priority: Normal
Assignee: Nobuyoshi Nakada
Category: build
Target version: 1.9.3
ruby -v: ruby 1.9.3p163 (2012-03-06 revision 34932) [i386-mingw32]


When attempted to use FD_SETSIZE preprocesor definition under Windows to increase number of file descriptions, found that configure script replicated it.

A simple configure invoke with `sh configure --enable-shared CPPFLAGS='-DFD_SETSIZE=32767' result in the following value returned by RbConfig:

<pre>
irb(main):001:0> require "rbconfig"
=> false
irb(main):002:0> RbConfig::CONFIG["CPPFLAGS"]
=> "-DFD_SETSIZE=32767  -DFD_SETSIZE=32767"
</pre>

Above is result from Ruby 1.9.3, and for ruby-trunk:

<pre>
irb(main):001:0> require "rbconfig"
=> false
irb(main):002:0> RbConfig::CONFIG["CPPFLAGS"]
=> "-DFD_SETSIZE=32767 -D_WIN32_WINNT=0x0501 -DFD_SETSIZE=32767"
</pre>


I'm not very versed on configure.in, so can't find the culprit of this duplication, sorry about that.


-- 
http://bugs.ruby-lang.org/