dep.rec        |  5 +++--
 doc/news.texi  |  3 +++
 doc/ood.texi   |  4 ++--
 doc/state.texi |  3 +++
 inode.go       | 13 +++++++++++++

diff --git a/dep.rec b/dep.rec
index 461ad420ff3f0aed5588d6d5e33e494d610dbc6526323c088f30b4aeac14d8b8..8274340ba92c530481012fbddb8c3a9d168a50e4dbdf3b00b807701f78715060 100644
--- a/dep.rec
+++ b/dep.rec
@@ -6,10 +6,11 @@
 %rec: Dependency
 %doc: Dependency information
 %mandatory: Type
-%allowed: Target Size CtimeSec CtimeNsec MtimeSec MtimeNsec Hash
-%unique: Type Target Size CtimeSec CtimeNsec MtimeSec MtimeNsec Hash
+%allowed: Target Size InodeNum CtimeSec CtimeNsec MtimeSec MtimeNsec Hash
+%unique: Type Target Size InodeNum CtimeSec CtimeNsec MtimeSec MtimeNsec Hash
 %type: Type enum ifcreate ifchange always stamp
 %type: Size int
+%type: InodeNum int
 %type: CtimeSec int
 %type: CtimeNsec int
 %type: MtimeSec int
diff --git a/doc/news.texi b/doc/news.texi
index bf3800de92480432342d4e91297d2b62a77877866e1f0bda250bf5096ac35dca..cc2609a3b0aacf319656c0bedad1adfc29c8b5e6440bd7d9646445936894cf8a 100644
--- a/doc/news.texi
+++ b/doc/news.texi
@@ -9,6 +9,9 @@ @item
     @command{redo-ifchange}'s @option{-f} option forces each target
     rebuilding. Comparing to @command{redo}, it will parallelize the
     process.
+@item
+    Inode's number is also stored as dependency information, just to
+    prevent possible @code{ctime} collision of two files.
 @end itemize
 
 @anchor{Release 1_22_0}
diff --git a/doc/ood.texi b/doc/ood.texi
index a9ab4ad9e048bc23837163994fc8ea44d8a8cfa9872e30da5a15a60b4a021dc4..efa07d516625da49faa33e201200d8090c090c95924a11791edf797e603956df 100644
--- a/doc/ood.texi
+++ b/doc/ood.texi
@@ -13,8 +13,8 @@ collision-resistant hash function of enough length. @command{goredo}
 uses @url{https://github.com/BLAKE3-team/BLAKE3, BLAKE3} with 256-bit
 output for that purpose.
 
-Also it stores file's size. Obviously if size differs, then file's
-content too and there is no need to read and hash it.
+Also it stores file's size and its inode number. Obviously if size
+differs, then file's content too and there is no need to read and hash it.
 
 @vindex REDO_INODE_TRUST
 But still it could be relatively expensive. So there are additional
diff --git a/doc/state.texi b/doc/state.texi
index 4a76847b7da472555babd1ea9a9dca21170175274e37cc94140998d9a06cc674..38cc997c8a3e7eb1780579bf2a93c2f2de8ee31f0d6cd29f86e4114eb204e7fe 100644
--- a/doc/state.texi
+++ b/doc/state.texi
@@ -18,8 +18,11 @@
 Type: ifchange
 Target: default.o.do
 Size: 123
+InodeNum: 2345
 CtimeSec: 1605721341
 CtimeNsec: 253305000
+MtimeSec: 1645606823
+MtimeNsec: 369936700
 Hash: f4929732f96f11e6d4ebe94536b5edef426d00ed0146853e37a87f4295e18eda
 
 Type: always
diff --git a/inode.go b/inode.go
index e95e99a19c090f94cb183ebbf248c66a3c4deabc0dd4b00c12f1742cd50d174e..baa4199ddd3448ce721ac28252c5aa4fcf300e5d5208f2ce59d5664e1a9e91a1 100644
--- a/inode.go
+++ b/inode.go
@@ -43,6 +43,7 @@ var InodeTrust InodeTrustType
 
 type Inode struct {
 	Size      int64
+	InodeNum  uint64
 	CtimeSec  int64
 	CtimeNsec int64
 	MtimeSec  int64
@@ -51,6 +52,9 @@ }
 
 func (our *Inode) Equals(their *Inode) bool {
 	if our.Size != their.Size {
+		return false
+	}
+	if our.InodeNum != their.InodeNum {
 		return false
 	}
 	switch InodeTrust {
@@ -72,6 +76,7 @@
 func (inode *Inode) RecfileFields() []recfile.Field {
 	return []recfile.Field{
 		{Name: "Size", Value: strconv.FormatInt(inode.Size, 10)},
+		{Name: "InodeNum", Value: strconv.FormatUint(inode.InodeNum, 10)},
 		{Name: "CtimeSec", Value: strconv.FormatInt(inode.CtimeSec, 10)},
 		{Name: "CtimeNsec", Value: strconv.FormatInt(inode.CtimeNsec, 10)},
 		{Name: "MtimeSec", Value: strconv.FormatInt(inode.MtimeSec, 10)},
@@ -95,6 +100,7 @@ 	mtimeSec := fi.ModTime().Unix()
 	mtimeNsec := fi.ModTime().UnixNano()
 	return &Inode{
 		Size:     fi.Size(),
+		InodeNum: uint64(stat.Ino),
 		CtimeSec: ctimeSec, CtimeNsec: ctimeNsec,
 		MtimeSec: mtimeSec, MtimeNsec: mtimeNsec,
 	}, nil
@@ -102,6 +108,7 @@ }
 
 func inodeFromRec(m map[string]string) (*Inode, error) {
 	size := m["Size"]
+	inodeNum := m["InodeNum"]
 	ctimeSec := m["CtimeSec"]
 	ctimeNsec := m["CtimeNsec"]
 	mtimeSec := m["MtimeSec"]
@@ -120,6 +127,12 @@ 	var err error
 	inode.Size, err = strconv.ParseInt(size, 10, 64)
 	if err != nil {
 		return nil, err
+	}
+	if inodeNum != "" {
+		inode.InodeNum, err = strconv.ParseUint(inodeNum, 10, 64)
+		if err != nil {
+			return nil, err
+		}
 	}
 	inode.CtimeSec, err = strconv.ParseInt(ctimeSec, 10, 64)
 	if err != nil {