diff --git a/Include/pymacconfig.h b/Include/pymacconfig.h
index 00459a03b980be..806e41955efd7f 100644
--- a/Include/pymacconfig.h
+++ b/Include/pymacconfig.h
@@ -1,90 +1,82 @@
-#ifndef PYMACCONFIG_H
-#define PYMACCONFIG_H
-     /*
-      * This file moves some of the autoconf magic to compile-time
-      * when building on MacOSX. This is needed for building 4-way
-      * universal binaries and for 64-bit universal binaries because
-      * the values redefined below aren't configure-time constant but
-      * only compile-time constant in these scenarios.
-      */
+// This file moves some of the autoconf magic to compile-time when building on
+// macOS. This is needed for building 4-way universal binaries and for 64-bit
+// universal binaries because the values redefined below aren't configure-time
+// constant but only compile-time constant in these scenarios.
 
-#if defined(__APPLE__)
+#ifndef PY_MACCONFIG_H
+#define PY_MACCONFIG_H
+#ifdef __APPLE__
 
-# undef SIZEOF_LONG
-# undef SIZEOF_PTHREAD_T
-# undef SIZEOF_SIZE_T
-# undef SIZEOF_TIME_T
-# undef SIZEOF_VOID_P
-# undef SIZEOF__BOOL
-# undef SIZEOF_UINTPTR_T
-# undef SIZEOF_PTHREAD_T
-# undef WORDS_BIGENDIAN
-# undef DOUBLE_IS_ARM_MIXED_ENDIAN_IEEE754
-# undef DOUBLE_IS_BIG_ENDIAN_IEEE754
-# undef DOUBLE_IS_LITTLE_ENDIAN_IEEE754
-# undef HAVE_GCC_ASM_FOR_X87
+#undef SIZEOF_LONG
+#undef SIZEOF_PTHREAD_T
+#undef SIZEOF_SIZE_T
+#undef SIZEOF_TIME_T
+#undef SIZEOF_VOID_P
+#undef SIZEOF__BOOL
+#undef SIZEOF_UINTPTR_T
+#undef SIZEOF_PTHREAD_T
+#undef WORDS_BIGENDIAN
+#undef DOUBLE_IS_ARM_MIXED_ENDIAN_IEEE754
+#undef DOUBLE_IS_BIG_ENDIAN_IEEE754
+#undef DOUBLE_IS_LITTLE_ENDIAN_IEEE754
+#undef HAVE_GCC_ASM_FOR_X87
 
-#    undef VA_LIST_IS_ARRAY
-#    if defined(__LP64__) && defined(__x86_64__)
-#        define VA_LIST_IS_ARRAY 1
-#    endif
-
-#    undef HAVE_LARGEFILE_SUPPORT
-#    ifndef __LP64__
-#         define HAVE_LARGEFILE_SUPPORT 1
-#    endif
-
-#    undef SIZEOF_LONG
-#    ifdef __LP64__
-#        define SIZEOF__BOOL            1
-#        define SIZEOF__BOOL            1
-#        define SIZEOF_LONG             8
-#        define SIZEOF_PTHREAD_T        8
-#        define SIZEOF_SIZE_T           8
-#        define SIZEOF_TIME_T           8
-#        define SIZEOF_VOID_P           8
-#        define SIZEOF_UINTPTR_T        8
-#        define SIZEOF_PTHREAD_T        8
-#    else
-#        ifdef __ppc__
-#           define SIZEOF__BOOL         4
-#        else
-#           define SIZEOF__BOOL         1
-#        endif
-#        define SIZEOF_LONG             4
-#        define SIZEOF_PTHREAD_T        4
-#        define SIZEOF_SIZE_T           4
-#        define SIZEOF_TIME_T           4
-#        define SIZEOF_VOID_P           4
-#        define SIZEOF_UINTPTR_T        4
-#        define SIZEOF_PTHREAD_T        4
-#    endif
+#undef VA_LIST_IS_ARRAY
+#if defined(__LP64__) && defined(__x86_64__)
+#  define VA_LIST_IS_ARRAY 1
+#endif
 
-#    if defined(__LP64__)
-     /* MacOSX 10.4 (the first release to support 64-bit code
-      * at all) only supports 64-bit in the UNIX layer.
-      * Therefore suppress the toolbox-glue in 64-bit mode.
-      */
+#undef HAVE_LARGEFILE_SUPPORT
+#ifndef __LP64__
+#   define HAVE_LARGEFILE_SUPPORT 1
+#endif
 
-    /* In 64-bit mode setpgrp always has no arguments, in 32-bit
-     * mode that depends on the compilation environment
-     */
-#       undef SETPGRP_HAVE_ARG
+#undef SIZEOF_LONG
+#ifdef __LP64__
+#  define SIZEOF__BOOL            1
+#  define SIZEOF__BOOL            1
+#  define SIZEOF_LONG             8
+#  define SIZEOF_PTHREAD_T        8
+#  define SIZEOF_SIZE_T           8
+#  define SIZEOF_TIME_T           8
+#  define SIZEOF_VOID_P           8
+#  define SIZEOF_UINTPTR_T        8
+#  define SIZEOF_PTHREAD_T        8
+#else
+#  ifdef __ppc__
+#     define SIZEOF__BOOL         4
+#  else
+#     define SIZEOF__BOOL         1
+#  endif
+#  define SIZEOF_LONG             4
+#  define SIZEOF_PTHREAD_T        4
+#  define SIZEOF_SIZE_T           4
+#  define SIZEOF_TIME_T           4
+#  define SIZEOF_VOID_P           4
+#  define SIZEOF_UINTPTR_T        4
+#  define SIZEOF_PTHREAD_T        4
+#endif
 
-#    endif
+// macOS 10.4 (the first release to support 64-bit code
+// at all) only supports 64-bit in the UNIX layer.
+// Therefore suppress the toolbox-glue in 64-bit mode.
+//
+// In 64-bit mode setpgrp always has no arguments, in 32-bit
+// mode that depends on the compilation environment
+#if defined(__LP64__)
+#   undef SETPGRP_HAVE_ARG
+#endif
 
 #ifdef __BIG_ENDIAN__
-#define WORDS_BIGENDIAN 1
-#define DOUBLE_IS_BIG_ENDIAN_IEEE754
+#  define WORDS_BIGENDIAN 1
+#  define DOUBLE_IS_BIG_ENDIAN_IEEE754
 #else
-#define DOUBLE_IS_LITTLE_ENDIAN_IEEE754
-#endif /* __BIG_ENDIAN */
+#  define DOUBLE_IS_LITTLE_ENDIAN_IEEE754
+#endif
 
 #ifdef __i386__
-# define HAVE_GCC_ASM_FOR_X87
+#  define HAVE_GCC_ASM_FOR_X87
 #endif
 
-
-#endif /* defined(_APPLE__) */
-
-#endif /* PYMACCONFIG_H */
+#endif   // __APPLE__
+#endif   // !PY_MACCONFIG_H