cmake unable to find libstdc++ - cmake

Question

(Using elementaryOS/Ubuntu)
I'm cross-compiling x265 and I encouraged annoying problem. For some reason cmake doesn't want to accept -static-libstdc++, because ld is apparently unable to find it. Cmake is built from Source Code, working pretty well without -static-libstdc++, if I then copy libstdc++-6.dll from mingw-w64 libs to folder with x265.exe, it works well, but I want it to build with it. mingw was built with this script and contains these libraries, but I don't know where is ld looking for them.
Here is output of cmake attempt:
-- cmake version 3.5.0-rc1
-- The C compiler identification is GNU 5.2.0
-- The CXX compiler identification is GNU 5.2.0
-- Check for working C compiler: /home/myname/mingw-w64/mingw-w64-x86_64/bin/x86_64-w64-mingw32-gcc
-- Check for working C compiler: /home/myname/mingw-w64/mingw-w64-x86_64/bin/x86_64-w64-mingw32-gcc -- works
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Detecting C compile features
-- Detecting C compile features - done
-- Check for working CXX compiler: /home/myname/mingw-w64/mingw-w64-x86_64/bin/x86_64-w64-mingw32-g++
-- Check for working CXX compiler: /home/myname/mingw-w64/mingw-w64-x86_64/bin/x86_64-w64-mingw32-g++ -- broken
CMake Error at /usr/local/share/cmake-3.5/Modules/CMakeTestCXXCompiler.cmake:54 (message):
The C++ compiler
"/home/myname/mingw-w64/mingw-w64-x86_64/bin/x86_64-w64-mingw32-g++" is not
able to compile a simple test program.
It fails with the following output:
Change Dir: /home/myname/x265/build/linux/12bit/CMakeFiles/CMakeTmp
Run Build Command:"/usr/bin/make" "cmTC_e7611/fast"
/usr/bin/make -f CMakeFiles/cmTC_e7611.dir/build.make
CMakeFiles/cmTC_e7611.dir/build
make[1]: Entering directory
`/home/myname/x265/build/linux/12bit/CMakeFiles/CMakeTmp'
Building CXX object CMakeFiles/cmTC_e7611.dir/testCXXCompiler.cxx.obj
/home/myname/mingw-w64/mingw-w64-x86_64/bin/x86_64-w64-mingw32-g++
-static-libgcc -static-libstdc++ -o
CMakeFiles/cmTC_e7611.dir/testCXXCompiler.cxx.obj -c
/home/myname/x265/build/linux/12bit/CMakeFiles/CMakeTmp/testCXXCompiler.cxx
Linking CXX executable cmTC_e7611.exe
/usr/local/bin/cmake -E cmake_link_script
CMakeFiles/cmTC_e7611.dir/link.txt --verbose=1
/usr/local/bin/cmake -E remove -f CMakeFiles/cmTC_e7611.dir/objects.a
/home/myname/mingw-w64/mingw-w64-x86_64/bin/x86_64-w64-mingw32-ar cr
CMakeFiles/cmTC_e7611.dir/objects.a #CMakeFiles/cmTC_e7611.dir/objects1.rsp
/home/myname/mingw-w64/mingw-w64-x86_64/bin/x86_64-w64-mingw32-g++
-static-libgcc -static-libstdc++ -Wl,--whole-archive
CMakeFiles/cmTC_e7611.dir/objects.a -Wl,--no-whole-archive -o
cmTC_e7611.exe -Wl,--out-implib,libcmTC_e7611.dll.a
-Wl,--major-image-version,0,--minor-image-version,0
#CMakeFiles/cmTC_e7611.dir/linklibs.rsp
/home/myname/mingw-w64/mingw-w64-x86_64/lib/gcc/x86_64-w64-mingw32/5.2.0/../../../../x86_64-w64-mingw32/bin/ld:
cannot find -lstdc++
collect2: error: ld returned 1 exit status
make[1]: *** [cmTC_e7611.exe] Error 1
make[1]: Leaving directory
`/home/myname/x265/build/linux/12bit/CMakeFiles/CMakeTmp'
make: *** [cmTC_e7611/fast] Error 2
CMake will not be able to correctly generate this project.
Call Stack (most recent call first):
CMakeLists.txt:19 (project)
-- Configuring incomplete, errors occurred!
See also "/home/myname/x265/build/linux/12bit/CMakeFiles/CMakeOutput.log".
See also "/home/myname/x265/build/linux/12bit/CMakeFiles/CMakeError.log".
make: *** No targets specified and no makefile found. Stop.
Cmake is run like code below.
cmake -DCMAKE_C_COMPILER='/home/myname/mingw-w64/mingw-w64-x86_64/bin/x86_64-w64-mingw32-gcc' -DCMAKE_CXX_COMPILER='/home/myname/mingw-w64/mingw-w64-x86_64/bin/x86_64-w64-mingw32-g++' -DCMAKE_RC_COMPILER='/home/myname/mingw-w64/mingw-w64-x86_64/bin/x86_64-w64-mingw32-windres' -DCMAKE_CXX_FLAGS="-static-libgcc -static-libstdc++" -DCMAKE_C_FLAGS="-static-libgcc -static-libstdc++" -DCMAKE_TOOLCHAIN_FILE='/home/myname/x265/build/linux/build.cmake' ../../../source -DHIGH_BIT_DEPTH=ON -DEXPORT_C_API=OFF -DENABLE_SHARED=OFF -DENABLE_CLI=OFF -DMAIN12=ON
make ${MAKEFLAGS}
build.cmake file is not much important here, but it contains:
SET(CMAKE_SYSTEM_NAME Windows)
SET(CMAKE_ASM_YASM_COMPILER yasm)
Any ideas how to make -static-libstdc++ work? I tried linking it in many folders, but I couldn't find out where is ld looking for it.

Answer 1

I managed to solve this. Source of my confusion was the fact that you can use -static-libgcc, so I thought even -static-libstdc++ should work. The problem was that there indeed were libraries, but not the .a files for libstdc++. These can be disabled using this parameter when using the script. Then both -static-lib options work well.
bash ./mingw-w64-build-3.6.7 --disable-shared