diff --git a/libdl/libdl.arm.map b/libdl/libdl.arm.map
index 2200cd4..1fdc1a7 100644
--- a/libdl/libdl.arm.map
+++ b/libdl/libdl.arm.map
@@ -17,8 +17,8 @@
 
 LIBC {
   global:
-    android_dlopen_ext;
-    dl_iterate_phdr;
+    android_dlopen_ext; # introduced=21
+    dl_iterate_phdr; # introduced-arm=21
     dl_unwind_find_exidx; # arm
     dladdr;
     dlclose;
@@ -31,7 +31,7 @@
 
 LIBC_N {
   global:
-    dlvsym;
+    dlvsym; # introduced=24
 } LIBC;
 
 LIBC_PLATFORM {
diff --git a/libdl/libdl.arm64.map b/libdl/libdl.arm64.map
index 8779e4c..28d2613 100644
--- a/libdl/libdl.arm64.map
+++ b/libdl/libdl.arm64.map
@@ -17,8 +17,8 @@
 
 LIBC {
   global:
-    android_dlopen_ext;
-    dl_iterate_phdr;
+    android_dlopen_ext; # introduced=21
+    dl_iterate_phdr; # introduced-arm=21
     dladdr;
     dlclose;
     dlerror;
@@ -30,7 +30,7 @@
 
 LIBC_N {
   global:
-    dlvsym;
+    dlvsym; # introduced=24
 } LIBC;
 
 LIBC_PLATFORM {
diff --git a/libdl/libdl.mips.map b/libdl/libdl.mips.map
index 8779e4c..28d2613 100644
--- a/libdl/libdl.mips.map
+++ b/libdl/libdl.mips.map
@@ -17,8 +17,8 @@
 
 LIBC {
   global:
-    android_dlopen_ext;
-    dl_iterate_phdr;
+    android_dlopen_ext; # introduced=21
+    dl_iterate_phdr; # introduced-arm=21
     dladdr;
     dlclose;
     dlerror;
@@ -30,7 +30,7 @@
 
 LIBC_N {
   global:
-    dlvsym;
+    dlvsym; # introduced=24
 } LIBC;
 
 LIBC_PLATFORM {
diff --git a/libdl/libdl.mips64.map b/libdl/libdl.mips64.map
index 8779e4c..28d2613 100644
--- a/libdl/libdl.mips64.map
+++ b/libdl/libdl.mips64.map
@@ -17,8 +17,8 @@
 
 LIBC {
   global:
-    android_dlopen_ext;
-    dl_iterate_phdr;
+    android_dlopen_ext; # introduced=21
+    dl_iterate_phdr; # introduced-arm=21
     dladdr;
     dlclose;
     dlerror;
@@ -30,7 +30,7 @@
 
 LIBC_N {
   global:
-    dlvsym;
+    dlvsym; # introduced=24
 } LIBC;
 
 LIBC_PLATFORM {
diff --git a/libdl/libdl.x86.map b/libdl/libdl.x86.map
index 8779e4c..28d2613 100644
--- a/libdl/libdl.x86.map
+++ b/libdl/libdl.x86.map
@@ -17,8 +17,8 @@
 
 LIBC {
   global:
-    android_dlopen_ext;
-    dl_iterate_phdr;
+    android_dlopen_ext; # introduced=21
+    dl_iterate_phdr; # introduced-arm=21
     dladdr;
     dlclose;
     dlerror;
@@ -30,7 +30,7 @@
 
 LIBC_N {
   global:
-    dlvsym;
+    dlvsym; # introduced=24
 } LIBC;
 
 LIBC_PLATFORM {
diff --git a/libdl/libdl.x86_64.map b/libdl/libdl.x86_64.map
index 8779e4c..28d2613 100644
--- a/libdl/libdl.x86_64.map
+++ b/libdl/libdl.x86_64.map
@@ -17,8 +17,8 @@
 
 LIBC {
   global:
-    android_dlopen_ext;
-    dl_iterate_phdr;
+    android_dlopen_ext; # introduced=21
+    dl_iterate_phdr; # introduced-arm=21
     dladdr;
     dlclose;
     dlerror;
@@ -30,7 +30,7 @@
 
 LIBC_N {
   global:
-    dlvsym;
+    dlvsym; # introduced=24
 } LIBC;
 
 LIBC_PLATFORM {