diff --git a/source/lib/external_libraries/openmp.h b/source/lib/external_libraries/openmp.h
deleted file mode 100644
index 626bbd8d92..0000000000
--- a/source/lib/external_libraries/openmp.h
+++ /dev/null
@@ -1,63 +0,0 @@
-/* Copyright (C) 2015 Wildfire Games.
- *
- * Permission is hereby granted, free of charge, to any person obtaining
- * a copy of this software and associated documentation files (the
- * "Software"), to deal in the Software without restriction, including
- * without limitation the rights to use, copy, modify, merge, publish,
- * distribute, sublicense, and/or sell copies of the Software, and to
- * permit persons to whom the Software is furnished to do so, subject to
- * the following conditions:
- *
- * The above copyright notice and this permission notice shall be included
- * in all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
- * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
- * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
- * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
- * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
- * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
- * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
- */
-
-#ifndef INCLUDED_EXTERNAL_LIBRARIES_OPENMP
-#define INCLUDED_EXTERNAL_LIBRARIES_OPENMP
-
-// allows removing all OpenMP-related code via #define ENABLE_OPENMP 0
-// before including this header. (useful during debugging, because the
-// VC debugger isn't able to display OpenMP private variables)
-#ifdef ENABLE_OPENMP
-# if ENABLE_OPENMP && !defined(_OPENMP)
-#  error "either enable OpenMP in the compiler settings or don't set ENABLE_OPENMP to 1"
-# endif
-#else	// no user preference; default to compiler setting
-# ifdef _OPENMP
-#  define ENABLE_OPENMP 1
-# else
-#  define ENABLE_OPENMP 0
-# endif
-#endif
-
-#if ENABLE_OPENMP
-# include <omp.h>
-#else
-# define omp_get_num_threads() 1
-# define omp_get_thread_num() 0
-# define omp_in_parallel() 0
-#endif
-
-// wrapper macro that evaluates to nothing if !ENABLE_OPENMP
-// (much more convenient than individual #if ENABLE_OPENMP)
-#if ENABLE_OPENMP
-# if MSC_VERSION
-#  define OMP(args) __pragma(omp args)
-# elif GCC_VERSION
-#  define OMP _Pragma("omp " #args)
-# else
-#  error "port"
-# endif
-#else
-# define OMP(args)
-#endif
-
-#endif	// #ifndef INCLUDED_EXTERNAL_LIBRARIES_OPENMP
diff --git a/source/lib/sysdep/os_cpu.h b/source/lib/sysdep/os_cpu.h
index 071e9dbab1..a00bfbfbb2 100644
--- a/source/lib/sysdep/os_cpu.h
+++ b/source/lib/sysdep/os_cpu.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2010 Wildfire Games.
+/* Copyright (C) 2021 Wildfire Games.
  *
  * Permission is hereby granted, free of charge, to any person obtaining
  * a copy of this software and associated documentation files (the
@@ -64,12 +64,6 @@ LIB_API uintptr_t os_cpu_ProcessorMask();
  **/
 LIB_API size_t os_cpu_NumProcessors();
 
-// note: we do not provide an os_cpu_CurrentProcessor routine. that would
-// require Windows 2003 or a lot of work. worse, its results would be
-// worthless because they may change immediately afterwards. instead,
-// the recommended approach is to pin OpenMP threads (whose ID can be
-// queried) to the processor with the same number.
-
 
 //-----------------------------------------------------------------------------
 // CPU and memory characteristics