diff --git a/common.mk b/common.mk
index 7ff4c563e998077f8f90351026411f4044b9a941..bf65ac0ed440888bb6dede0b8972de3c4958b0d1 100644
--- a/common.mk
+++ b/common.mk
@@ -1079,6 +1079,7 @@ help: PHONY
 	"  https://bugs.ruby-lang.org/projects/ruby/wiki/DeveloperHowto" \
 	$(MESSAGE_END)
 
+# AUTOGENERATED DEPENDENCIES START
 addr2line.$(OBJEXT): {$(VPATH)}addr2line.h
 array.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 array.$(OBJEXT): {$(VPATH)}defines.h
@@ -2090,3 +2091,4 @@ vm_trace.$(OBJEXT): {$(VPATH)}thread_native.h
 vm_trace.$(OBJEXT): {$(VPATH)}vm_core.h
 vm_trace.$(OBJEXT): {$(VPATH)}vm_debug.h
 vm_trace.$(OBJEXT): {$(VPATH)}vm_opts.h
+# AUTOGENERATED DEPENDENCIES END
diff --git a/enc/depend b/enc/depend
index 902441a972fa8780b0e1a8528cbcff3201637fd5..8a577f633077bab8bbffb3c6db2396d0802ee231 100644
--- a/enc/depend
+++ b/enc/depend
@@ -156,6 +156,7 @@ clean-srcs:
 
 <%# vim: set ft=eruby noexpandtab ts=8 sw=2 : -%>
 
+# AUTOGENERATED DEPENDENCIES START
 enc/euc_jp.$(OBJEXT): enc/jis/props.kwd
 enc/shift_jis.$(OBJEXT): enc/jis/props.kwd
 enc/windows_31j.$(OBJEXT): enc/jis/props.kwd
@@ -489,3 +490,4 @@ enc/trans/utf_16_32.$(OBJEXT): missing.h
 enc/trans/utf_16_32.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 enc/trans/utf_16_32.$(OBJEXT): st.h
 enc/trans/utf_16_32.$(OBJEXT): subst.h
+# AUTOGENERATED DEPENDENCIES END
diff --git a/ext/-test-/bignum/depend b/ext/-test-/bignum/depend
index 72d6e2d8840deaedaa604afc11ad573c863cf97d..8f1660cbe3805d0046c59e122edd879f98a838a5 100644
--- a/ext/-test-/bignum/depend
+++ b/ext/-test-/bignum/depend
@@ -4,6 +4,7 @@ intpack.o: intpack.c
 mul.o: mul.c
 str2big.o: str2big.c
 
+# AUTOGENERATED DEPENDENCIES START
 bigzero.o: $(top_srcdir)/internal.h
 big2str.o: $(top_srcdir)/internal.h
 big2str.o: $(arch_hdrdir)/ruby/config.h
@@ -66,3 +67,4 @@ str2big.o: $(hdrdir)/ruby/missing.h
 str2big.o: $(hdrdir)/ruby/ruby.h
 str2big.o: $(hdrdir)/ruby/st.h
 str2big.o: $(hdrdir)/ruby/subst.h
+# AUTOGENERATED DEPENDENCIES END
diff --git a/ext/-test-/debug/depend b/ext/-test-/debug/depend
index e1955562f00c14c1c92c1f98af3e213deb64af97..fdbfff8c423ec4810c018c66e68a92a6b8b27ace 100644
--- a/ext/-test-/debug/depend
+++ b/ext/-test-/debug/depend
@@ -1,3 +1,4 @@
+# AUTOGENERATED DEPENDENCIES START
 init.o: $(arch_hdrdir)/ruby/config.h
 init.o: $(top_srcdir)/include/ruby.h
 init.o: $(hdrdir)/ruby/defines.h
@@ -22,3 +23,4 @@ profile_frames.o: $(hdrdir)/ruby/missing.h
 profile_frames.o: $(hdrdir)/ruby/ruby.h
 profile_frames.o: $(hdrdir)/ruby/st.h
 profile_frames.o: $(hdrdir)/ruby/subst.h
+# AUTOGENERATED DEPENDENCIES END
diff --git a/ext/-test-/exception/depend b/ext/-test-/exception/depend
index 49139f7a77e697d5f983bdda89419a899022de30..c1140d5709361ba0f68ec8b5d0283e6e89fb5985 100644
--- a/ext/-test-/exception/depend
+++ b/ext/-test-/exception/depend
@@ -1,3 +1,4 @@
+# AUTOGENERATED DEPENDENCIES START
 dataerror.o: $(arch_hdrdir)/ruby/config.h
 dataerror.o: $(hdrdir)/ruby/defines.h
 dataerror.o: $(hdrdir)/ruby/intern.h
@@ -31,3 +32,4 @@ init.o: $(hdrdir)/ruby/missing.h
 init.o: $(hdrdir)/ruby/ruby.h
 init.o: $(hdrdir)/ruby/st.h
 init.o: $(hdrdir)/ruby/subst.h
+# AUTOGENERATED DEPENDENCIES END
diff --git a/ext/-test-/file/depend b/ext/-test-/file/depend
index 7ed9f38c4e724bbfa8dd19fcf86d13d9721e2376..90ca40c101ed0b23c17f7c516e74d8f6c1250f07 100644
--- a/ext/-test-/file/depend
+++ b/ext/-test-/file/depend
@@ -1,3 +1,4 @@
+# AUTOGENERATED DEPENDENCIES START
 fs.o: $(arch_hdrdir)/ruby/config.h
 fs.o: $(hdrdir)/ruby/defines.h
 fs.o: $(hdrdir)/ruby/encoding.h
@@ -26,3 +27,4 @@ stat.o: $(hdrdir)/ruby/oniguruma.h
 stat.o: $(hdrdir)/ruby/ruby.h
 stat.o: $(hdrdir)/ruby/st.h
 stat.o: $(hdrdir)/ruby/subst.h
+# AUTOGENERATED DEPENDENCIES END
diff --git a/ext/-test-/string/depend b/ext/-test-/string/depend
index 9dab96d633da4fb77b0f960e7a3531be22ba109c..8a1c2c3764d64b457e015949d2dc4631e926ce11 100644
--- a/ext/-test-/string/depend
+++ b/ext/-test-/string/depend
@@ -1,3 +1,4 @@
+# AUTOGENERATED DEPENDENCIES START
 coderange.o: $(arch_hdrdir)/ruby/config.h
 coderange.o: $(hdrdir)/ruby/defines.h
 coderange.o: $(hdrdir)/ruby/encoding.h
@@ -88,3 +89,4 @@ set_len.o: $(hdrdir)/ruby/missing.h
 set_len.o: $(hdrdir)/ruby/ruby.h
 set_len.o: $(hdrdir)/ruby/st.h
 set_len.o: $(hdrdir)/ruby/subst.h
+# AUTOGENERATED DEPENDENCIES END
diff --git a/ext/-test-/tracepoint/depend b/ext/-test-/tracepoint/depend
index cfb08685bd721e6ba01a6e40e3f93730a8e33d00..4d4203e14514fcaf741a1a3da4e8284e83a03175 100644
--- a/ext/-test-/tracepoint/depend
+++ b/ext/-test-/tracepoint/depend
@@ -1,3 +1,4 @@
+# AUTOGENERATED DEPENDENCIES START
 gc_hook.o: $(arch_hdrdir)/ruby/config.h
 gc_hook.o: $(hdrdir)/ruby/debug.h
 gc_hook.o: $(hdrdir)/ruby/defines.h
@@ -14,3 +15,4 @@ tracepoint.o: $(hdrdir)/ruby/missing.h
 tracepoint.o: $(hdrdir)/ruby/ruby.h
 tracepoint.o: $(hdrdir)/ruby/st.h
 tracepoint.o: $(hdrdir)/ruby/subst.h
+# AUTOGENERATED DEPENDENCIES END
diff --git a/ext/-test-/wait_for_single_fd/depend b/ext/-test-/wait_for_single_fd/depend
index 58047c7edeaca2d23545f37d409623fb3789894a..2d2afb199c31100703558e7c1dbecb2d3774cbbc 100644
--- a/ext/-test-/wait_for_single_fd/depend
+++ b/ext/-test-/wait_for_single_fd/depend
@@ -1,3 +1,4 @@
+# AUTOGENERATED DEPENDENCIES START
 wait_for_single_fd.o: $(arch_hdrdir)/ruby/config.h
 wait_for_single_fd.o: $(hdrdir)/ruby/defines.h
 wait_for_single_fd.o: $(hdrdir)/ruby/encoding.h
@@ -8,3 +9,4 @@ wait_for_single_fd.o: $(hdrdir)/ruby/oniguruma.h
 wait_for_single_fd.o: $(hdrdir)/ruby/ruby.h
 wait_for_single_fd.o: $(hdrdir)/ruby/st.h
 wait_for_single_fd.o: $(hdrdir)/ruby/subst.h
+# AUTOGENERATED DEPENDENCIES END
diff --git a/ext/bigdecimal/depend b/ext/bigdecimal/depend
index 3450250d8acbf9dd1f5dbdfa74f58c04ec55f12e..329bb90cc89d6ab8ab6310532eba633820c7ed9d 100644
--- a/ext/bigdecimal/depend
+++ b/ext/bigdecimal/depend
@@ -1,3 +1,4 @@
+# AUTOGENERATED DEPENDENCIES START
 bigdecimal.o: $(arch_hdrdir)/ruby/config.h
 bigdecimal.o: bigdecimal.h
 bigdecimal.o: $(hdrdir)/ruby/defines.h
@@ -7,3 +8,4 @@ bigdecimal.o: $(hdrdir)/ruby/ruby.h
 bigdecimal.o: $(hdrdir)/ruby/st.h
 bigdecimal.o: $(hdrdir)/ruby/subst.h
 bigdecimal.o: $(hdrdir)/ruby/util.h
+# AUTOGENERATED DEPENDENCIES END
diff --git a/ext/coverage/depend b/ext/coverage/depend
index 6f253d96b46c2a3475a2f77311f0e620cf7e3a6f..50c355c05d7578baa544aad6c01f22e65f5edf7a 100644
--- a/ext/coverage/depend
+++ b/ext/coverage/depend
@@ -9,7 +9,10 @@ $(OBJS): $(HDRS) $(ruby_headers) \
   $(top_srcdir)/thread_pthread.h \
   $(top_srcdir)/internal.h \
   $(top_srcdir)/include/ruby/thread_native.h
+
+# AUTOGENERATED DEPENDENCIES START
 coverage.o: $(top_srcdir)/ccan/check_type/check_type.h
 coverage.o: $(top_srcdir)/ccan/container_of/container_of.h
 coverage.o: $(top_srcdir)/ccan/list/list.h
 coverage.o: $(top_srcdir)/ccan/str/str.h
+# AUTOGENERATED DEPENDENCIES END
diff --git a/ext/date/depend b/ext/date/depend
index 2c9006e50fb7fd2247c030b57999ab327cef9401..a4c9d7b202c994b61720f5fca0e6fdac31f5edef 100644
--- a/ext/date/depend
+++ b/ext/date/depend
@@ -1,3 +1,4 @@
+# AUTOGENERATED DEPENDENCIES START
 date_core.o: $(arch_hdrdir)/ruby/config.h
 date_core.o: date_tmx.h
 date_core.o: $(top_srcdir)/include/ruby.h
@@ -41,3 +42,4 @@ date_strptime.o: $(hdrdir)/ruby/regex.h
 date_strptime.o: $(hdrdir)/ruby/ruby.h
 date_strptime.o: $(hdrdir)/ruby/st.h
 date_strptime.o: $(hdrdir)/ruby/subst.h
+# AUTOGENERATED DEPENDENCIES END
diff --git a/ext/digest/bubblebabble/depend b/ext/digest/bubblebabble/depend
index 9e5466c722a77d4bdcae25941d96577b9ee7865e..6ef6d7d593ed81f3006ce0bf7f60c9261670c282 100644
--- a/ext/digest/bubblebabble/depend
+++ b/ext/digest/bubblebabble/depend
@@ -1,3 +1,4 @@
+# AUTOGENERATED DEPENDENCIES START
 bubblebabble.o: $(arch_hdrdir)/ruby/config.h
 bubblebabble.o: $(top_srcdir)/ext/digest/digest.h
 bubblebabble.o: $(top_srcdir)/include/ruby.h
@@ -7,3 +8,4 @@ bubblebabble.o: $(hdrdir)/ruby/missing.h
 bubblebabble.o: $(hdrdir)/ruby/ruby.h
 bubblebabble.o: $(hdrdir)/ruby/st.h
 bubblebabble.o: $(hdrdir)/ruby/subst.h
+# AUTOGENERATED DEPENDENCIES END
diff --git a/ext/digest/depend b/ext/digest/depend
index d3afb8459678390422da3bf09e427515a0286ed5..64f5d7649eaffbf78a2e3f182f6361af3f1d9b42 100644
--- a/ext/digest/depend
+++ b/ext/digest/depend
@@ -1,3 +1,4 @@
+# AUTOGENERATED DEPENDENCIES START
 digest.o: $(arch_hdrdir)/ruby/config.h
 digest.o: digest.h
 digest.o: $(top_srcdir)/include/ruby.h
@@ -7,3 +8,4 @@ digest.o: $(hdrdir)/ruby/missing.h
 digest.o: $(hdrdir)/ruby/ruby.h
 digest.o: $(hdrdir)/ruby/st.h
 digest.o: $(hdrdir)/ruby/subst.h
+# AUTOGENERATED DEPENDENCIES END
diff --git a/ext/digest/md5/depend b/ext/digest/md5/depend
index 6d3a0dc512667c43c6f79ceced9a8037bba17ee3..bc89ec0481b5d3dba7dfb5e30a20d3b09308999f 100644
--- a/ext/digest/md5/depend
+++ b/ext/digest/md5/depend
@@ -1,4 +1,6 @@
 md5.o: md5.c md5.h $(srcdir)/../defs.h
+
+# AUTOGENERATED DEPENDENCIES START
 md5init.o: $(arch_hdrdir)/ruby/config.h
 md5init.o: $(top_srcdir)/ext/digest/digest.h
 md5init.o: md5ossl.h
@@ -10,3 +12,4 @@ md5init.o: $(hdrdir)/ruby/ruby.h
 md5init.o: $(hdrdir)/ruby/st.h
 md5init.o: $(hdrdir)/ruby/subst.h
 md5ossl.o: md5ossl.h
+# AUTOGENERATED DEPENDENCIES END
diff --git a/ext/digest/rmd160/depend b/ext/digest/rmd160/depend
index 647d3aeb70529b8ef44e9b416ca27ca7f8c2d9cf..d53a87ff337e57e71deda821d1a3632f2bb8c8dd 100644
--- a/ext/digest/rmd160/depend
+++ b/ext/digest/rmd160/depend
@@ -1,4 +1,6 @@
 rmd160.o: rmd160.c rmd160.h $(srcdir)/../defs.h $(HDRS) $(ruby_headers)
+
+# AUTOGENERATED DEPENDENCIES START
 rmd160init.o: $(arch_hdrdir)/ruby/config.h
 rmd160init.o: $(hdrdir)/ruby/defines.h
 rmd160init.o: $(hdrdir)/ruby/intern.h
@@ -19,3 +21,4 @@ rmd160ossl.o: $(hdrdir)/ruby/subst.h
 rmd160ossl.o: $(top_srcdir)/ext/digest/defs.h
 rmd160ossl.o: $(top_srcdir)/include/ruby.h
 rmd160ossl.o: rmd160ossl.h
+# AUTOGENERATED DEPENDENCIES END
diff --git a/ext/digest/sha1/depend b/ext/digest/sha1/depend
index b2bd833cf045e0d169985a5b8a4136ed636367d1..8f334f13255bde5892c40bb89bf980a484be7f65 100644
--- a/ext/digest/sha1/depend
+++ b/ext/digest/sha1/depend
@@ -1,5 +1,6 @@
 sha1.o: sha1.c sha1.h $(srcdir)/../defs.h
 
+# AUTOGENERATED DEPENDENCIES START
 sha1init.o: $(arch_hdrdir)/ruby/config.h
 sha1init.o: $(top_srcdir)/ext/digest/digest.h
 sha1init.o: sha1ossl.h
@@ -20,3 +21,4 @@ sha1ossl.o: $(hdrdir)/ruby/missing.h
 sha1ossl.o: $(hdrdir)/ruby/ruby.h
 sha1ossl.o: $(hdrdir)/ruby/st.h
 sha1ossl.o: $(hdrdir)/ruby/subst.h
+# AUTOGENERATED DEPENDENCIES END
diff --git a/ext/digest/sha2/depend b/ext/digest/sha2/depend
index 938c7f0fd0078a1b499304d43353849b399a79fc..065faaf5decfe3a91b59f2c536e7e0144e5b8435 100644
--- a/ext/digest/sha2/depend
+++ b/ext/digest/sha2/depend
@@ -1,4 +1,6 @@
 sha2.o: sha2.c sha2.h $(srcdir)/../defs.h $(HDRS) $(ruby_headers)
+
+# AUTOGENERATED DEPENDENCIES START
 sha2init.o: $(arch_hdrdir)/ruby/config.h
 sha2init.o: $(top_srcdir)/ext/digest/digest.h
 sha2init.o: sha2ossl.h
@@ -19,3 +21,4 @@ sha2ossl.o: $(hdrdir)/ruby/missing.h
 sha2ossl.o: $(hdrdir)/ruby/ruby.h
 sha2ossl.o: $(hdrdir)/ruby/st.h
 sha2ossl.o: $(hdrdir)/ruby/subst.h
+# AUTOGENERATED DEPENDENCIES END
diff --git a/ext/json/generator/depend b/ext/json/generator/depend
index 72f1c130b2265cc628b466962b453f35c76eb740..84d79d62b7a08e0c79350a6c60af01ca524d71d5 100644
--- a/ext/json/generator/depend
+++ b/ext/json/generator/depend
@@ -1,6 +1,9 @@
 $(OBJS): $(ruby_headers)
 generator.o: generator.c generator.h $(srcdir)/../fbuffer/fbuffer.h
+
+# AUTOGENERATED DEPENDENCIES START
 generator.o: $(hdrdir)/ruby/encoding.h
 generator.o: $(hdrdir)/ruby/oniguruma.h
 generator.o: $(hdrdir)/ruby/re.h
 generator.o: $(hdrdir)/ruby/regex.h
+# AUTOGENERATED DEPENDENCIES END
diff --git a/ext/json/parser/depend b/ext/json/parser/depend
index 87c123305aa0c21b0bb2b1090f311c99758cee2c..8b2335245e2e4e54e4ea9f34208be6e84de1a259 100644
--- a/ext/json/parser/depend
+++ b/ext/json/parser/depend
@@ -1,5 +1,8 @@
 $(OBJS): $(ruby_headers)
 parser.o: parser.c parser.h $(srcdir)/../fbuffer/fbuffer.h
+
+# AUTOGENERATED DEPENDENCIES START
 parser.o: parser.rl
 parser.o: $(hdrdir)/ruby/encoding.h
 parser.o: $(hdrdir)/ruby/oniguruma.h
+# AUTOGENERATED DEPENDENCIES END
diff --git a/ext/nkf/depend b/ext/nkf/depend
index 264af81823bddd76df4079c449f724dd099221bf..c0a00c8407f5d6fa3bfd553ed7596cef5004ed39 100644
--- a/ext/nkf/depend
+++ b/ext/nkf/depend
@@ -1,3 +1,4 @@
+# AUTOGENERATED DEPENDENCIES START
 nkf.o: $(arch_hdrdir)/ruby/config.h
 nkf.o: nkf-utf8/config.h
 nkf.o: nkf-utf8/nkf.c
@@ -12,3 +13,4 @@ nkf.o: $(hdrdir)/ruby/oniguruma.h
 nkf.o: $(hdrdir)/ruby/ruby.h
 nkf.o: $(hdrdir)/ruby/st.h
 nkf.o: $(hdrdir)/ruby/subst.h
+# AUTOGENERATED DEPENDENCIES END
diff --git a/ext/objspace/depend b/ext/objspace/depend
index 05fee909a117b8d8334572fbaef6bd61f39223b7..23d7081092b283c9a327551e84870126bebd9630 100644
--- a/ext/objspace/depend
+++ b/ext/objspace/depend
@@ -1,3 +1,4 @@
+# AUTOGENERATED DEPENDENCIES START
 object_tracing.o: $(top_srcdir)/internal.h
 objspace_dump.o: $(topdir)/id.h
 objspace_dump.o: $(top_srcdir)/internal.h
@@ -50,3 +51,4 @@ objspace_dump.o: $(hdrdir)/ruby/missing.h
 objspace_dump.o: $(hdrdir)/ruby/ruby.h
 objspace_dump.o: $(hdrdir)/ruby/st.h
 objspace_dump.o: $(hdrdir)/ruby/subst.h
+# AUTOGENERATED DEPENDENCIES END
diff --git a/ext/openssl/depend b/ext/openssl/depend
index c81cfaf7968d66e05f7fd1fc7fcd49bb89fa0ad2..29a09d0dbd8168dcd16cb8b2ee67e226e2d86078 100644
--- a/ext/openssl/depend
+++ b/ext/openssl/depend
@@ -1,3 +1,4 @@
+# AUTOGENERATED DEPENDENCIES START
 openssl_missing.o: openssl_missing.h
 ossl.o: $(arch_hdrdir)/ruby/config.h
 ossl.o: openssl_missing.h
@@ -1023,3 +1024,4 @@ ossl_x509store.o: $(hdrdir)/ruby/ruby.h
 ossl_x509store.o: $(hdrdir)/ruby/st.h
 ossl_x509store.o: $(hdrdir)/ruby/subst.h
 ossl_x509store.o: $(hdrdir)/ruby/thread.h
+# AUTOGENERATED DEPENDENCIES END
diff --git a/ext/pty/depend b/ext/pty/depend
index b33617630ce6d19194f7bddb743588fe7c6c2b43..2fec61240d6759497c70c4510c69129d251b5027 100644
--- a/ext/pty/depend
+++ b/ext/pty/depend
@@ -1,3 +1,4 @@
+# AUTOGENERATED DEPENDENCIES START
 pty.o: $(top_srcdir)/internal.h
 pty.o: $(arch_hdrdir)/ruby/config.h
 pty.o: $(hdrdir)/ruby/defines.h
@@ -10,3 +11,4 @@ pty.o: $(hdrdir)/ruby/ruby.h
 pty.o: $(hdrdir)/ruby/st.h
 pty.o: $(hdrdir)/ruby/subst.h
 pty.o: $(hdrdir)/ruby/util.h
+# AUTOGENERATED DEPENDENCIES END
diff --git a/ext/rbconfig/sizeof/depend b/ext/rbconfig/sizeof/depend
index cd45428c8c71c469472eb29aed2cc7f742659c9b..328557b402fe23063a9664e96abf5c9620df14e3 100644
--- a/ext/rbconfig/sizeof/depend
+++ b/ext/rbconfig/sizeof/depend
@@ -1,6 +1,8 @@
 sizes.c: $(top_srcdir)/tool/generic_erb.rb $(top_srcdir)/template/sizes.c.tmpl $(top_srcdir)/configure.in
 	$(Q) $(RUBY) $(top_srcdir)/tool/generic_erb.rb --output=$@ \
 		$(top_srcdir)/template/sizes.c.tmpl $(top_srcdir)/configure.in
+
+# AUTOGENERATED DEPENDENCIES START
 sizes.o: $(arch_hdrdir)/ruby/config.h
 sizes.o: $(hdrdir)/ruby/defines.h
 sizes.o: $(hdrdir)/ruby/intern.h
@@ -8,3 +10,4 @@ sizes.o: $(hdrdir)/ruby/missing.h
 sizes.o: $(hdrdir)/ruby/ruby.h
 sizes.o: $(hdrdir)/ruby/st.h
 sizes.o: $(hdrdir)/ruby/subst.h
+# AUTOGENERATED DEPENDENCIES END
diff --git a/ext/readline/depend b/ext/readline/depend
index d6ec852d0a903c9adb874ea6220006117d19e6a1..40d1bbdb300695f2052a91dc53f4060b72a6714c 100644
--- a/ext/readline/depend
+++ b/ext/readline/depend
@@ -1,3 +1,4 @@
+# AUTOGENERATED DEPENDENCIES START
 readline.o: $(top_srcdir)/internal.h
 readline.o: $(arch_hdrdir)/ruby/config.h
 readline.o: $(hdrdir)/ruby/defines.h
@@ -10,3 +11,4 @@ readline.o: $(hdrdir)/ruby/ruby.h
 readline.o: $(hdrdir)/ruby/st.h
 readline.o: $(hdrdir)/ruby/subst.h
 readline.o: $(hdrdir)/ruby/thread.h
+# AUTOGENERATED DEPENDENCIES END
diff --git a/ext/ripper/depend b/ext/ripper/depend
index 774f8fd327c886758897bb5e5fc18ba6fdb8c19d..db2dd15aca6852d2415226eb5baf92f8f85dff86 100644
--- a/ext/ripper/depend
+++ b/ext/ripper/depend
@@ -43,6 +43,7 @@ ripper.E: ripper.c
 	$(ECHO) preprocessing ripper.c
 	$(Q) $(CC) -E $(CPPFLAGS) ripper.c | $(RUBY) $(srcdir)/tools/strip.rb > $@
 
+# AUTOGENERATED DEPENDENCIES START
 ripper.o: {$(VPATH)}id.h
 ripper.o: $(top_srcdir)/internal.h
 ripper.o: {$(VPATH)}lex.c
@@ -67,3 +68,4 @@ ripper.o: $(hdrdir)/ruby/ruby.h
 ripper.o: $(hdrdir)/ruby/st.h
 ripper.o: $(hdrdir)/ruby/subst.h
 ripper.o: $(hdrdir)/ruby/util.h
+# AUTOGENERATED DEPENDENCIES END
diff --git a/ext/sdbm/depend b/ext/sdbm/depend
index 8a6b5b742a56cb82ba2efc200c0ed60f58f15017..e81716c888460bdca627c20afaa99fbdd1ccd628 100644
--- a/ext/sdbm/depend
+++ b/ext/sdbm/depend
@@ -1,3 +1,4 @@
+# AUTOGENERATED DEPENDENCIES START
 _sdbm.o: $(arch_hdrdir)/ruby/config.h
 _sdbm.o: sdbm.h
 _sdbm.o: $(hdrdir)/ruby/defines.h
@@ -11,3 +12,4 @@ init.o: $(hdrdir)/ruby/missing.h
 init.o: $(hdrdir)/ruby/ruby.h
 init.o: $(hdrdir)/ruby/st.h
 init.o: $(hdrdir)/ruby/subst.h
+# AUTOGENERATED DEPENDENCIES END
diff --git a/ext/socket/depend b/ext/socket/depend
index c995df13945ba3505e061d44e45fb6aac8858eb4..9661c0c51986ade7d473ffc5acb8ea2c386ee7c9 100644
--- a/ext/socket/depend
+++ b/ext/socket/depend
@@ -5,6 +5,7 @@ constdefs.h constdefs.c : $(srcdir)/mkconstants.rb
 	@echo "generating constant definitions"
 	@$(RUBY) $(srcdir)/mkconstants.rb -H constdefs.h -o constdefs.c
 
+# AUTOGENERATED DEPENDENCIES START
 ancdata.o: $(top_srcdir)/internal.h
 ancdata.o: $(arch_hdrdir)/ruby/config.h
 ancdata.o: constdefs.h
@@ -246,3 +247,4 @@ unixsocket.o: $(hdrdir)/ruby/st.h
 unixsocket.o: $(hdrdir)/ruby/subst.h
 unixsocket.o: $(hdrdir)/ruby/thread.h
 unixsocket.o: $(hdrdir)/ruby/util.h
+# AUTOGENERATED DEPENDENCIES END
diff --git a/ext/strscan/depend b/ext/strscan/depend
index b2be40948e77af9d1933babb2e1abada2bc95d44..e7e589232962c7456cc76ae6b966fd518b83ef1f 100644
--- a/ext/strscan/depend
+++ b/ext/strscan/depend
@@ -1,3 +1,4 @@
+# AUTOGENERATED DEPENDENCIES START
 strscan.o: $(top_srcdir)/regenc.h
 strscan.o: $(top_srcdir)/regint.h
 strscan.o: $(arch_hdrdir)/ruby/config.h
@@ -11,3 +12,4 @@ strscan.o: $(hdrdir)/ruby/regex.h
 strscan.o: $(hdrdir)/ruby/ruby.h
 strscan.o: $(hdrdir)/ruby/st.h
 strscan.o: $(hdrdir)/ruby/subst.h
+# AUTOGENERATED DEPENDENCIES END
diff --git a/ext/syslog/depend b/ext/syslog/depend
index c71b73fb0c84eab7af8b93bc844a2c52e6404114..9ba4d05eda546b3f257a6f11b3c0f9ff99dc6011 100644
--- a/ext/syslog/depend
+++ b/ext/syslog/depend
@@ -1,3 +1,4 @@
+# AUTOGENERATED DEPENDENCIES START
 syslog.o: $(arch_hdrdir)/ruby/config.h
 syslog.o: $(hdrdir)/ruby/defines.h
 syslog.o: $(hdrdir)/ruby/intern.h
@@ -6,3 +7,4 @@ syslog.o: $(hdrdir)/ruby/ruby.h
 syslog.o: $(hdrdir)/ruby/st.h
 syslog.o: $(hdrdir)/ruby/subst.h
 syslog.o: $(hdrdir)/ruby/util.h
+# AUTOGENERATED DEPENDENCIES END