Index: llvm/trunk/CMakeLists.txt
===================================================================
--- llvm/trunk/CMakeLists.txt
+++ llvm/trunk/CMakeLists.txt
@@ -570,7 +570,7 @@
 endif()
 option(LLVM_LINK_LLVM_DYLIB "Link tools against the libllvm dynamic library" OFF)
 if(MSVC)
-  option(LLVM_BUILD_LLVM_C_DYLIB "Build LLVM-C.dll (Windows only)" OFF)
+  option(LLVM_BUILD_LLVM_C_DYLIB "Build LLVM-C.dll (Windows only)" ON)
 else()
   option(LLVM_BUILD_LLVM_C_DYLIB "Build libllvm-c re-export library (Darwin only)" OFF)
 endif()
Index: llvm/trunk/tools/llvm-shlib/CMakeLists.txt
===================================================================
--- llvm/trunk/tools/llvm-shlib/CMakeLists.txt
+++ llvm/trunk/tools/llvm-shlib/CMakeLists.txt
@@ -132,18 +132,40 @@
     set(GEN_UNDERSCORE "")
   endif()
 
+  # Set this name here, not used in multi conf loop,
+  # but add script will pick the right one.
+  set(LIBSFILE ${CMAKE_BINARY_DIR}/${CMAKE_CFG_INTDIR}/libllvm-c.args)
+
   # Get the full name to the libs so the python script understands them.
   foreach(lib ${LIB_NAMES})
     list(APPEND FULL_LIB_NAMES ${CMAKE_BINARY_DIR}/${CMAKE_CFG_INTDIR}/lib/${lib}.lib)
   endforeach()
 
+  # Need to seperate lib names with newlines.
+  string(REPLACE ";" "\n" FILE_CONTENT "${FULL_LIB_NAMES}")
+
+  if(NOT "${CMAKE_CFG_INTDIR}" STREQUAL ".")
+    foreach(BUILD_MODE ${CMAKE_CONFIGURATION_TYPES})
+      # Replace the special string with a per config directory.
+      string(REPLACE ${CMAKE_CFG_INTDIR} ${BUILD_MODE} PER_CONF_CONTENT "${FILE_CONTENT}")
+
+      # Write out the full lib names into file to be read by the python script.
+      # One libsfile per build, the add_custom_command should expand
+      # ${CMAKE_CFG_INTDIR} correctly and select the right one.
+      file(WRITE ${CMAKE_BINARY_DIR}/${BUILD_MODE}/libllvm-c.args "${PER_CONF_CONTENT}")
+    endforeach()
+  else()
+    # Write out the full lib names into file to be read by the python script.
+    file(WRITE ${LIBSFILE} "${FILE_CONTENT}")
+  endif()
+
   # Generate the exports file dynamically.
   set(GEN_SCRIPT ${CMAKE_CURRENT_SOURCE_DIR}/gen-msvc-exports.py)
 
   set(LLVM_EXPORTED_SYMBOL_FILE ${CMAKE_BINARY_DIR}/${CMAKE_CFG_INTDIR}/libllvm-c.exports)
 
   add_custom_command(OUTPUT ${LLVM_EXPORTED_SYMBOL_FILE}
-    COMMAND ${PYTHON_EXECUTABLE} ${GEN_SCRIPT} ${FULL_LIB_NAMES} ${GEN_UNDERSCORE} --nm ${LLVM_TOOLS_BINARY_DIR}/llvm-nm -o ${LLVM_EXPORTED_SYMBOL_FILE}
+    COMMAND ${PYTHON_EXECUTABLE} ${GEN_SCRIPT} --libsfile ${LIBSFILE} ${GEN_UNDERSCORE} --nm ${LLVM_TOOLS_BINARY_DIR}/llvm-nm -o ${LLVM_EXPORTED_SYMBOL_FILE}
     DEPENDS ${LIB_NAMES} llvm-nm
     COMMENT "Generating export list for LLVM-C"
     VERBATIM )
Index: llvm/trunk/tools/llvm-shlib/gen-msvc-exports.py
===================================================================
--- llvm/trunk/tools/llvm-shlib/gen-msvc-exports.py
+++ llvm/trunk/tools/llvm-shlib/gen-msvc-exports.py
@@ -83,6 +83,10 @@
     parser = argparse.ArgumentParser('gen-msvc-exports')
 
     parser.add_argument(
+        '-i', '--libsfile', help='file with list of libs, new line separated',
+        action='store', default=None
+    )
+    parser.add_argument(
         '-o', '--output', help='output filename', default='LLVM-C.exports'
     )
     parser.add_argument('-u', '--underscore',
@@ -93,12 +97,19 @@
         '--nm', help='path to the llvm-nm executable', default='llvm-nm'
     )
     parser.add_argument(
-        'libs', metavar='LIBS', nargs='+', help='list of libraries to generate export from'
+        'libs', metavar='LIBS', nargs='*', help='list of libraries to generate export from'
     )
 
     ns = parser.parse_args()
 
-    gen_llvm_c_export(ns.output, ns.underscore, ns.libs, ns.nm)
+    libs = ns.libs
+
+    # Add if we where given a libsfile add it to the libs.
+    if ns.libsfile:
+        with open(ns.libsfile) as f:
+            libs.extend(f.read().splitlines())
+
+    gen_llvm_c_export(ns.output, ns.underscore, libs, ns.nm)
 
 
 if __name__ == '__main__':
Index: llvm/trunk/utils/release/build_llvm_package.bat
===================================================================
--- llvm/trunk/utils/release/build_llvm_package.bat
+++ llvm/trunk/utils/release/build_llvm_package.bat
@@ -52,7 +52,17 @@
 
 
 REM Setting CMAKE_CL_SHOWINCLUDES_PREFIX to work around PR27226.
-set cmake_flags=-DCMAKE_BUILD_TYPE=Release -DLLVM_ENABLE_ASSERTIONS=ON -DLLVM_INSTALL_TOOLCHAIN_ONLY=ON -DCMAKE_INSTALL_UCRT_LIBRARIES=ON -DCLANG_FORMAT_VS_VERSION=%clang_format_vs_version% -DPACKAGE_VERSION=%package_version% -DLLDB_RELOCATABLE_PYTHON=1 -DLLDB_TEST_COMPILER=%cd%\build32_stage0\bin\clang.exe -DCMAKE_CL_SHOWINCLUDES_PREFIX="Note: including file: "
+set cmake_flags=^
+	-DCMAKE_BUILD_TYPE=Release ^
+	-DLLVM_ENABLE_ASSERTIONS=ON ^
+	-DLLVM_INSTALL_TOOLCHAIN_ONLY=ON ^
+	-DLLVM_BUILD_LLVM_C_DYLIB=ON ^
+	-DCMAKE_INSTALL_UCRT_LIBRARIES=ON ^
+	-DCLANG_FORMAT_VS_VERSION=%clang_format_vs_version% ^
+	-DPACKAGE_VERSION=%package_version% ^
+	-DLLDB_RELOCATABLE_PYTHON=1 ^
+	-DLLDB_TEST_COMPILER=%cd%\build32_stage0\bin\clang.exe ^
+	-DCMAKE_CL_SHOWINCLUDES_PREFIX="Note: including file: "
 
 REM TODO: Run the "check-all" tests.