[Bug target/56279] Unwanted directory is added to include search path when building for MingGW with --native-system-header-dir

["karlson2k at gmail dot com" <gcc-bugzilla@gcc.gnu.org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56279

Evgeny Grin <karlson2k at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Target|i686-w64-mingw32,           |i686-pc-mingw32,
                   |x86_64-w64-mingw32          |i686-w64-mingw32,
                   |                            |x86_64-w64-mingw32

--- Comment #2 from Evgeny Grin <karlson2k at gmail dot com> 2013-02-10 23:47:59 UTC ---
Result on MinGW32 compiler (tried from mingw site or compiled from sources -
results are the same):

$ echo int main(){return 1;} | gcc.exe -v -E -x c -
Using built-in specs.                                                          
                                                                               
                               COLLECT_GCC=gcc.exe
Target: mingw32
Configured with: ../gcc-4.7.2/configure
--enable-languages=c,c++,ada,fortran,objc,obj-c++ --disable-sjlj-exceptions
--with-dwarf2 --enable-shared --enable-libgomp --disable-win32-registry
--enable-libstdcxx-debug --disable-build-poststage1-with-cxx
--enable-version-specific-runtime-libs --build=mingw32 --prefix=/mingw
Thread model: win32
gcc version 4.7.2 (GCC)
COLLECT_GCC_OPTIONS='-v' '-E' '-mtune=i386' '-march=i386'
 t:/mingw32/bin/../libexec/gcc/mingw32/4.7.2/cc1.exe -E -quiet -v -iprefix
t:\mingw32\bin\../lib/gcc/mingw32/4.7.2/ - -mtune=i386 -march=i386
ignoring nonexistent directory
"t:\mingw32\bin\../lib/gcc/mingw32/4.7.2/../../../../mingw32/include"
ignoring duplicate directory
"t:/mingw32/lib/gcc/../../lib/gcc/mingw32/4.7.2/include"
ignoring nonexistent directory "/mingw/include"
ignoring duplicate directory "t:/mingw32/lib/gcc/../../include"
ignoring duplicate directory
"t:/mingw32/lib/gcc/../../lib/gcc/mingw32/4.7.2/include-fixed"
ignoring nonexistent directory
"t:/mingw32/lib/gcc/../../lib/gcc/mingw32/4.7.2/../../../../mingw32/include"
ignoring nonexistent directory "/mingw/include"
#include "..." search starts here:
#include <...> search starts here:
 t:\mingw32\bin\../lib/gcc/mingw32/4.7.2/include
 t:\mingw32\bin\../lib/gcc/mingw32/4.7.2/../../../../include
 t:\mingw32\bin\../lib/gcc/mingw32/4.7.2/include-fixed
End of search list.
# 1 "<stdin>"
# 1 "<command-line>"
# 1 "<stdin>"
int main(){return 1;}
COMPILER_PATH=t:/mingw32/bin/../libexec/gcc/mingw32/4.7.2/;t:/mingw32/bin/../libexec/gcc/;t:/mingw32/bin/../lib/gcc/mingw32/4.7.2/../../../../mingw32/bin/
LIBRARY_PATH=t:/mingw32/bin/../lib/gcc/mingw32/4.7.2/;t:/mingw32/bin/../lib/gcc/;t:/mingw32/bin/../lib/gcc/mingw32/4.7.2/../../../../mingw32/lib/;t:/mingw32/bin/../lib/gcc/mingw32/4.7.2/../../../
COLLECT_GCC_OPTIONS='-v' '-E' '-mtune=i386' '-march=i386'

Two "/mingw/include" in Posix format in GCC! In practice GCC try to use
/mingw/include directory on current drive (in my case on drive T: ), but I may
have a different MinGW version installed there.