Build error when trying to compiler LDC for MinGW

cmake -G Ninja -DLLVM_ROOT_DIR="D:\ldc_env\llvm\bin" -DLIBCONFIG_INCLUDE_DIR="D:\ldc_env\libconfig-1.4.9\lib" -DLIBCONFIG_LIBRARY="D:\ldc_env\libconfig-1.4.9\lib\libconfig++.dll.a" -DCMAKE_BUILD_TYPE=Release ..
-- The C compiler identification is GNU 5.1.0
-- The CXX compiler identification is GNU 5.1.0
-- Check for working C compiler using: Ninja
-- Check for working C compiler using: Ninja -- 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 using: Ninja
-- Check for working CXX compiler using: Ninja -- works
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- Found LLVM: D:/ldc_env/llvm/bin (found suitable version "3.7.0svn", minimum required is "3.1")
-- Found LibConfig: D:/ldc_env/libconfig-1.4.9/lib
-- LDC version identifier: c1872c
-- Check if the system is big endian
-- Searching 16 bit integer
-- Looking for sys/types.h
-- Looking for sys/types.h - found
-- Looking for stdint.h
-- Looking for stdint.h - found
-- Looking for stddef.h
-- Looking for stddef.h - found
-- Check size of unsigned short
-- Check size of unsigned short - done
-- Using unsigned short
-- Check if the system is big endian - little endian
-- Using path for Intrinsics.td: D:/ldc_env/llvm/bin/include
-- Looking for _SC_ARG_MAX
-- Looking for _SC_ARG_MAX - not found
-- Check size of void*
-- Check size of void* - done
-- Configuring done
-- Generating done
CMake Warning (dev):
  Policy CMP0058 is not set: Ninja requires custom command byproducts to be
  explicit.  Run "cmake --help-policy CMP0058" for policy details.  Use the
  cmake_policy command to set the policy and suppress this warning.

  This project specifies custom command DEPENDS on files in the build tree
  that are not specified as the OUTPUT or BYPRODUCTS of any
  add_custom_command or add_custom_target:

   bin/ldc2.conf

  For compatibility with versions of CMake that did not have the BYPRODUCTS
  option, CMake is generating phony rules for such files to convince 'ninja'
  to build.

  Project authors should add the missing BYPRODUCTS or OUTPUT options to the
  custom commands that produce these files.
This warning is for project developers.  Use -Wno-dev to suppress it.

-- Build files have been written to: D:/ldc_env/ldc/build
ninja -j 8
ninja: error: 'D:/ldc_env/libconfig-1.4.9/lib/libconfig++.dll.a', needed by 'bin/ldc2.exe', missing and no known rule to make it