diff --git a/liba/include/stdint.h b/liba/include/stdint.h
index 34f8c5f03..db274d276 100644
--- a/liba/include/stdint.h
+++ b/liba/include/stdint.h
@@ -11,6 +11,9 @@ typedef signed short int16_t;
 typedef signed int int32_t;
 typedef signed long long int64_t;
 
+typedef unsigned int uintptr_t;
+typedef signed int intptr_t;
+
 typedef uint8_t uint_fast8_t;
 typedef uint16_t uint_fast16_t;
 typedef uint32_t uint_fast32_t;
diff --git a/liba/test/stdint.c b/liba/test/stdint.c
index 4165837ec..04645b838 100644
--- a/liba/test/stdint.c
+++ b/liba/test/stdint.c
@@ -13,6 +13,9 @@ QUIZ_CASE(liba_stdint_size) {
   assert(sizeof(int16_t) == 2);
   assert(sizeof(int32_t) == 4);
   assert(sizeof(int64_t) == 8);
+
+  assert(sizeof(uintptr_t) == sizeof(void *));
+  assert(sizeof(intptr_t) == sizeof(void *));
 }
 
 QUIZ_CASE(liba_stdint_signedness) {
@@ -25,4 +28,7 @@ QUIZ_CASE(liba_stdint_signedness) {
   assert_unsigned(uint16_t);
   assert_unsigned(uint32_t);
   assert_unsigned(uint64_t);
+
+  assert_signed(intptr_t);
+  assert_unsigned(uintptr_t);
 }