[Bug preprocessor/56686] gcc cannot find include header file

["lostdj at gmail dot com" <gcc-bugzilla@gcc.gnu.org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56686

--- Comment #7 from lostdj at gmail dot com 2013-04-25 14:09:41 UTC ---
Created attachment 29939
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=29939
testcase

It's funny that I just wanted to report almost identical issue. Can't believe
no one had encountered this before.

MinGW, GCC 4.7.0.
Attached test case is a bit different from author's original, yet similar:
"inc1.h: No such file or directory"
If you change one include path in makefile from -I./ to -I., everything
compiles without errors.

>From gcc -v with -I./:
#include "..." search starts here:
#include <...> search starts here:
 ./inc
 d:\bin\mingw\bin\../lib/gcc/mingw32/4.7.0/include
 d:\bin\mingw\bin\../lib/gcc/mingw32/4.7.0/../../../../include
 d:\bin\mingw\bin\../lib/gcc/mingw32/4.7.0/include-fixed

And -I.:
#include "..." search starts here:
#include <...> search starts here:
 ./inc
 .
 d:\bin\mingw\bin\../lib/gcc/mingw32/4.7.0/include
 d:\bin\mingw\bin\../lib/gcc/mingw32/4.7.0/../../../../include
 d:\bin\mingw\bin\../lib/gcc/mingw32/4.7.0/include-fixed

***

Aaand on Linux with GCC 4.4.6 everything is fine. No errors. 
-v -I./:
#include "..." search starts here:
#include <...> search starts here:
 ./inc/
 ./
 /usr/local/include
 /usr/lib/gcc/i686-redhat-linux/4.4.6/include
 /usr/include

-v -I.:
#include "..." search starts here:
#include <...> search starts here:
 ./inc/
 .
 /usr/local/include
 /usr/lib/gcc/i686-redhat-linux/4.4.6/include
 /usr/include

***

So whom is to blame: GCC or MinGW?