diff --git a/pkg/libc/musl/datamap.go b/pkg/libc/musl/datamap.go
index 1e1eff5..09117bb 100644
--- a/pkg/libc/musl/datamap.go
+++ b/pkg/libc/musl/datamap.go
@@ -6,17 +6,17 @@ import (
 )
 
 type musl struct {
-	PThreadSize int64 `sizeof:"__pthread" yaml:"pthread_size"`
-	PThreadTSD  int64 `offsetof:"__pthread.tsd" yaml:"pthread_tsd"`
+	PThreadSize int64 `sizeof:"__pthread"`
+	PThreadTSD  int64 `offsetof:"__pthread.tsd"`
 }
 
 func (m *musl) Layout() runtimedata.RuntimeData {
 	return &libc.Layout{
 		PThreadSize:             m.PThreadSize,
 		PThreadSpecific1stblock: m.PThreadTSD,
-		// TODO(kakkoyun): Extract.
-		PThreadKeyData:     8,
-		PThreadKeyDataSize: 16,
+		PThreadKeyData:          0, // unused.
+		// pthread_key_t: TYPEDEF unsigned pthread_key_t;
+		PThreadKeyDataSize: 8,
 	}
 }
 
diff --git a/pkg/libc/musl/layout/amd64/1.1.11 - 1.1.15.yaml b/pkg/libc/musl/layout/amd64/1.1.11 - 1.1.15.yaml
index d524428..fc60478 100644
--- a/pkg/libc/musl/layout/amd64/1.1.11 - 1.1.15.yaml	
+++ b/pkg/libc/musl/layout/amd64/1.1.11 - 1.1.15.yaml	
@@ -1,4 +1,4 @@
-pthread_key_data: 8
-pthread_key_data_size: 16
+pthread_key_data: 0
+pthread_key_data_size: 8
 pthread_size: 336
 pthread_specific_1stblock: 152
diff --git a/pkg/libc/musl/layout/amd64/1.1.16 - 1.1.19.yaml b/pkg/libc/musl/layout/amd64/1.1.16 - 1.1.19.yaml
index f9da311..3dc268d 100644
--- a/pkg/libc/musl/layout/amd64/1.1.16 - 1.1.19.yaml	
+++ b/pkg/libc/musl/layout/amd64/1.1.16 - 1.1.19.yaml	
@@ -1,4 +1,4 @@
-pthread_key_data: 8
-pthread_key_data_size: 16
+pthread_key_data: 0
+pthread_key_data_size: 8
 pthread_size: 280
 pthread_specific_1stblock: 152
diff --git a/pkg/libc/musl/layout/amd64/1.1.22 - 1.1.24.yaml b/pkg/libc/musl/layout/amd64/1.1.22 - 1.1.24.yaml
index e984445..dfd0ef7 100644
--- a/pkg/libc/musl/layout/amd64/1.1.22 - 1.1.24.yaml	
+++ b/pkg/libc/musl/layout/amd64/1.1.22 - 1.1.24.yaml	
@@ -1,4 +1,4 @@
-pthread_key_data: 8
-pthread_key_data_size: 16
+pthread_key_data: 0
+pthread_key_data_size: 8
 pthread_size: 224
 pthread_specific_1stblock: 136
diff --git a/pkg/libc/musl/layout/amd64/1.2.2 - 1.2.4.yaml b/pkg/libc/musl/layout/amd64/1.2.2 - 1.2.4.yaml
index d0ba477..89a6092 100644
--- a/pkg/libc/musl/layout/amd64/1.2.2 - 1.2.4.yaml	
+++ b/pkg/libc/musl/layout/amd64/1.2.2 - 1.2.4.yaml	
@@ -1,4 +1,4 @@
-pthread_key_data: 8
-pthread_key_data_size: 16
+pthread_key_data: 0
+pthread_key_data_size: 8
 pthread_size: 200
 pthread_specific_1stblock: 128
diff --git a/pkg/libc/musl/layout/amd64/= 1.1.20.yaml b/pkg/libc/musl/layout/amd64/= 1.1.20.yaml
index 885caa9..9dbf157 100644
--- a/pkg/libc/musl/layout/amd64/= 1.1.20.yaml	
+++ b/pkg/libc/musl/layout/amd64/= 1.1.20.yaml	
@@ -1,4 +1,4 @@
-pthread_key_data: 8
-pthread_key_data_size: 16
+pthread_key_data: 0
+pthread_key_data_size: 8
 pthread_size: 240
 pthread_specific_1stblock: 152
diff --git a/pkg/libc/musl/layout/amd64/= 1.1.4.yaml b/pkg/libc/musl/layout/amd64/= 1.1.4.yaml
index 4eddef7..f1904c5 100644
--- a/pkg/libc/musl/layout/amd64/= 1.1.4.yaml	
+++ b/pkg/libc/musl/layout/amd64/= 1.1.4.yaml	
@@ -1,4 +1,4 @@
-pthread_key_data: 8
-pthread_key_data_size: 16
+pthread_key_data: 0
+pthread_key_data_size: 8
 pthread_size: 288
 pthread_specific_1stblock: 144
diff --git a/pkg/libc/musl/layout/amd64/= 1.1.5.yaml b/pkg/libc/musl/layout/amd64/= 1.1.5.yaml
index 3602bf3..3cfa8f9 100644
--- a/pkg/libc/musl/layout/amd64/= 1.1.5.yaml	
+++ b/pkg/libc/musl/layout/amd64/= 1.1.5.yaml	
@@ -1,4 +1,4 @@
-pthread_key_data: 8
-pthread_key_data_size: 16
+pthread_key_data: 0
+pthread_key_data_size: 8
 pthread_size: 296
 pthread_specific_1stblock: 144
diff --git a/pkg/libc/musl/layout/arm64/1.1.16 - 1.1.19.yaml b/pkg/libc/musl/layout/arm64/1.1.16 - 1.1.19.yaml
index f9da311..3dc268d 100644
--- a/pkg/libc/musl/layout/arm64/1.1.16 - 1.1.19.yaml	
+++ b/pkg/libc/musl/layout/arm64/1.1.16 - 1.1.19.yaml	
@@ -1,4 +1,4 @@
-pthread_key_data: 8
-pthread_key_data_size: 16
+pthread_key_data: 0
+pthread_key_data_size: 8
 pthread_size: 280
 pthread_specific_1stblock: 152
diff --git a/pkg/libc/musl/layout/arm64/1.1.22 - 1.1.24.yaml b/pkg/libc/musl/layout/arm64/1.1.22 - 1.1.24.yaml
index e984445..dfd0ef7 100644
--- a/pkg/libc/musl/layout/arm64/1.1.22 - 1.1.24.yaml	
+++ b/pkg/libc/musl/layout/arm64/1.1.22 - 1.1.24.yaml	
@@ -1,4 +1,4 @@
-pthread_key_data: 8
-pthread_key_data_size: 16
+pthread_key_data: 0
+pthread_key_data_size: 8
 pthread_size: 224
 pthread_specific_1stblock: 136
diff --git a/pkg/libc/musl/layout/arm64/1.2.2 - 1.2.4.yaml b/pkg/libc/musl/layout/arm64/1.2.2 - 1.2.4.yaml
index 20d00ff..62ad422 100644
--- a/pkg/libc/musl/layout/arm64/1.2.2 - 1.2.4.yaml	
+++ b/pkg/libc/musl/layout/arm64/1.2.2 - 1.2.4.yaml	
@@ -1,4 +1,4 @@
-pthread_key_data: 8
-pthread_key_data_size: 16
+pthread_key_data: 0
+pthread_key_data_size: 8
 pthread_size: 200
 pthread_specific_1stblock: 112
diff --git a/pkg/libc/musl/layout/arm64/= 1.1.15.yaml b/pkg/libc/musl/layout/arm64/= 1.1.15.yaml
index d524428..fc60478 100644
--- a/pkg/libc/musl/layout/arm64/= 1.1.15.yaml	
+++ b/pkg/libc/musl/layout/arm64/= 1.1.15.yaml	
@@ -1,4 +1,4 @@
-pthread_key_data: 8
-pthread_key_data_size: 16
+pthread_key_data: 0
+pthread_key_data_size: 8
 pthread_size: 336
 pthread_specific_1stblock: 152
diff --git a/pkg/libc/musl/layout/arm64/= 1.1.20.yaml b/pkg/libc/musl/layout/arm64/= 1.1.20.yaml
index 885caa9..9dbf157 100644
--- a/pkg/libc/musl/layout/arm64/= 1.1.20.yaml	
+++ b/pkg/libc/musl/layout/arm64/= 1.1.20.yaml	
@@ -1,4 +1,4 @@
-pthread_key_data: 8
-pthread_key_data_size: 16
+pthread_key_data: 0
+pthread_key_data_size: 8
 pthread_size: 240
 pthread_specific_1stblock: 152
diff --git a/pkg/libc/musl/musl_test.go b/pkg/libc/musl/musl_test.go
index e790f97..ae5f355 100644
--- a/pkg/libc/musl/musl_test.go
+++ b/pkg/libc/musl/musl_test.go
@@ -23,8 +23,8 @@ func Test_getLayoutForArch(t *testing.T) {
 			want: &libc.Layout{
 				PThreadSize:             200,
 				PThreadSpecific1stblock: 128,
-				PThreadKeyData:          8,
-				PThreadKeyDataSize:      16,
+				PThreadKeyData:          0,
+				PThreadKeyDataSize:      0x8,
 			},
 		},
 		{
@@ -34,8 +34,8 @@ func Test_getLayoutForArch(t *testing.T) {
 			want: &libc.Layout{
 				PThreadSize:             200,
 				PThreadSpecific1stblock: 112,
-				PThreadKeyData:          8,
-				PThreadKeyDataSize:      16,
+				PThreadKeyData:          0,
+				PThreadKeyDataSize:      0x8,
 			},
 		},
 		{
@@ -45,8 +45,8 @@ func Test_getLayoutForArch(t *testing.T) {
 			want: &libc.Layout{
 				PThreadSize:             280,
 				PThreadSpecific1stblock: 152,
-				PThreadKeyData:          8,
-				PThreadKeyDataSize:      16,
+				PThreadKeyData:          0,
+				PThreadKeyDataSize:      0x8,
 			},
 		},
 		{
@@ -56,8 +56,8 @@ func Test_getLayoutForArch(t *testing.T) {
 			want: &libc.Layout{
 				PThreadSize:             280,
 				PThreadSpecific1stblock: 152,
-				PThreadKeyData:          8,
-				PThreadKeyDataSize:      16,
+				PThreadKeyData:          0,
+				PThreadKeyDataSize:      0x8,
 			},
 		},
 	}