diff --git a/Documentation/process/magic-number.rst b/Documentation/process/magic-number.rst
index eb2db3608a152c872f7ad951e778ee8be9958aeb..f48c6c6efaf718b1f10c278f9adf01ab0986a31f 100644
--- a/Documentation/process/magic-number.rst
+++ b/Documentation/process/magic-number.rst
@@ -69,7 +69,6 @@ Changelog::
 Magic Name            Number           Structure                File
 ===================== ================ ======================== ==========================================
 PG_MAGIC              'P'              pg_{read,write}_hdr      ``include/linux/pg.h``
-CMAGIC                0x0111           user                     ``include/linux/a.out.h``
 HDLC_MAGIC            0x239e           n_hdlc                   ``drivers/char/n_hdlc.c``
 APM_BIOS_MAGIC        0x4101           apm_user                 ``arch/x86/kernel/apm_32.c``
 FASYNC_MAGIC          0x4601           fasync_struct            ``include/linux/fs.h``
diff --git a/Documentation/translations/it_IT/process/magic-number.rst b/Documentation/translations/it_IT/process/magic-number.rst
index 86ef47906f37005ae0d3bf7d45335be83f6a34a6..27f60133fbe5ff027d37ea271a86233ef5ec8eec 100644
--- a/Documentation/translations/it_IT/process/magic-number.rst
+++ b/Documentation/translations/it_IT/process/magic-number.rst
@@ -75,7 +75,6 @@ Registro dei cambiamenti::
 Nome magico           Numero           Struttura                File
 ===================== ================ ======================== ==========================================
 PG_MAGIC              'P'              pg_{read,write}_hdr      ``include/linux/pg.h``
-CMAGIC                0x0111           user                     ``include/linux/a.out.h``
 HDLC_MAGIC            0x239e           n_hdlc                   ``drivers/char/n_hdlc.c``
 APM_BIOS_MAGIC        0x4101           apm_user                 ``arch/x86/kernel/apm_32.c``
 FASYNC_MAGIC          0x4601           fasync_struct            ``include/linux/fs.h``
diff --git a/Documentation/translations/zh_CN/process/magic-number.rst b/Documentation/translations/zh_CN/process/magic-number.rst
index cbefdcbfbf5349a5b69b3318f3f2f8783ecf30d7..520cc5cf4d63a5f5a23189fc42e8d4867ea6afb4 100644
--- a/Documentation/translations/zh_CN/process/magic-number.rst
+++ b/Documentation/translations/zh_CN/process/magic-number.rst
@@ -58,7 +58,6 @@ Linux 魔术数
 魔术数名              数字             结构                     文件
 ===================== ================ ======================== ==========================================
 PG_MAGIC              'P'              pg_{read,write}_hdr      ``include/linux/pg.h``
-CMAGIC                0x0111           user                     ``include/linux/a.out.h``
 HDLC_MAGIC            0x239e           n_hdlc                   ``drivers/char/n_hdlc.c``
 APM_BIOS_MAGIC        0x4101           apm_user                 ``arch/x86/kernel/apm_32.c``
 FASYNC_MAGIC          0x4601           fasync_struct            ``include/linux/fs.h``
diff --git a/Documentation/translations/zh_TW/process/magic-number.rst b/Documentation/translations/zh_TW/process/magic-number.rst
index 7fd6e494467b65efb141ec5cc4494944650c1d6c..7d6debd0117e4810e15a7c66bedd3f804b329732 100644
--- a/Documentation/translations/zh_TW/process/magic-number.rst
+++ b/Documentation/translations/zh_TW/process/magic-number.rst
@@ -61,7 +61,6 @@ Linux 魔術數
 魔術數名              數字             結構                     文件
 ===================== ================ ======================== ==========================================
 PG_MAGIC              'P'              pg_{read,write}_hdr      ``include/linux/pg.h``
-CMAGIC                0x0111           user                     ``include/linux/a.out.h``
 HDLC_MAGIC            0x239e           n_hdlc                   ``drivers/char/n_hdlc.c``
 APM_BIOS_MAGIC        0x4101           apm_user                 ``arch/x86/kernel/apm_32.c``
 FASYNC_MAGIC          0x4601           fasync_struct            ``include/linux/fs.h``
diff --git a/include/uapi/linux/a.out.h b/include/uapi/linux/a.out.h
index 5fafde3798e57cd6bd05b34e9831de392432ea04..bb15da96df2a10f34964e820fbaded2d2be96b25 100644
--- a/include/uapi/linux/a.out.h
+++ b/include/uapi/linux/a.out.h
@@ -70,9 +70,6 @@ enum machine_type {
    The first page is unmapped to help trap NULL pointer references */
 #define QMAGIC 0314
 
-/* Code indicating core file.  */
-#define CMAGIC 0421
-
 #if !defined (N_BADMAG)
 #define N_BADMAG(x)	  (N_MAGIC(x) != OMAGIC		\
 			&& N_MAGIC(x) != NMAGIC		\