[Bug other/66394] New: ICE in -flto -fmerge-all-constants -fno-use-linker-plugin targetting i686-w64-mingw32

[sthalik at misaki dot pl]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66394

            Bug ID: 66394
           Summary: ICE in -flto -fmerge-all-constants
                    -fno-use-linker-plugin targetting i686-w64-mingw32
           Product: gcc
           Version: 5.1.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: other
          Assignee: unassigned at gcc dot gnu.org
          Reporter: sthalik at misaki dot pl
  Target Milestone: ---

Compiling as follows:

[ 76%] Building CXX object
modules/imgproc/CMakeFiles/opencv_imgproc.dir/src/color.cpp.obj
cd /d C:\Users\Administrator\dev\opentrack-win32\opencv\build2\modules\imgproc
&& C:\mingw-w64\i686-5.1.0-posix-dwarf-rt
_v4-rev0\mingw32\bin\i686-w64-mingw32-g++.exe    -fmerge-all-constants
--save-temps -fPIC   -fsigned-char -mstackrealign
 -W -Wall -Werror=return-type -Werror=address -Werror=sequence-point -Wformat
-Werror=format-security -Wmissing-declarat
ions -Wundef -Winit-self -Wpointer-arith -Wshadow -Wsign-promo -Wno-narrowing
-Wno-delete-non-virtual-dtor -fdiagnostics
-show-option -fomit-frame-pointer -ffast-math -msse -msse2 -mfpmath=sse
-ffunction-sections -O2 -ffast-math -flto -fno-u
se-linker-plugin -march=i686 -mtune=corei7-avx -mfpmath=both -msse -msse2
-mno-sse3 -mno-avx -frename-registers  -DNDEBU
G @CMakeFiles/opencv_imgproc.dir/includes_CXX.rsp    -Winvalid-pch -o
CMakeFiles\opencv_imgproc.dir\src\color.cpp.obj -c

C:\Users\Administrator\dev\opentrack-win32\opencv\modules\imgproc\src\color.cpp

C:\Users\Administrator\dev\opentrack-win32\opencv\modules\imgproc\src\color.cpp:4425:1:
internal compiler error: Segmentation fault

Not all flags are needed, enough to trigger is -O3 -flto -fno-use-linker-plugin
-fmerge-all-constants