diff --git a/internal/bits.h b/internal/bits.h
index 698ab3e2194..64e6ac6896b 100644
--- a/internal/bits.h
+++ b/internal/bits.h
@@ -28,7 +28,7 @@
 #include "ruby/internal/config.h"
 #include <limits.h>             /* for CHAR_BITS */
 #include <stdint.h>             /* for uintptr_t */
-#include "internal/compilers.h" /* for MSC_VERSION_SINCE */
+#include "internal/compilers.h" /* for __has_builtin */
 
 #ifdef _MSC_VER
 # include <stdlib.h>            /* for _byteswap_uint64 */
diff --git a/internal/compilers.h b/internal/compilers.h
index a19cade7051..c99b9afbfe7 100644
--- a/internal/compilers.h
+++ b/internal/compilers.h
@@ -18,9 +18,6 @@
 #include "ruby/internal/has/warning.h"
 #include "ruby/backward/2/gcc_version_since.h"
 
-#define MSC_VERSION_SINCE(_)   RBIMPL_COMPILER_SINCE(MSVC, (_) / 100, (_) % 100, 0)
-#define MSC_VERSION_BEFORE(_)  RBIMPL_COMPILER_BEFORE(MSVC, (_) / 100, (_) % 100, 0)
-
 #ifndef __has_attribute
 # define __has_attribute(...) RBIMPL_HAS_ATTRIBUTE(__VA_ARGS__)
 #endif
diff --git a/parser_bits.h b/parser_bits.h
index f894dde33e5..058f0beadad 100644
--- a/parser_bits.h
+++ b/parser_bits.h
@@ -28,7 +28,7 @@
 #include "ruby/internal/config.h"
 #include <limits.h>             /* for CHAR_BITS */
 #include <stdint.h>             /* for uintptr_t */
-#include "internal/compilers.h" /* for MSC_VERSION_SINCE */
+#include "internal/compilers.h" /* for __has_builtin */
 
 #ifdef _MSC_VER
 # include <stdlib.h>            /* for _byteswap_uint64 */