Update "Available in" comments to include _BSD_SOURCE/_GNU_SOURCE.
Change-Id: I22045a486e6dd73f4bb0912c140da28f8818fc41
diff --git a/libc/include/string.h b/libc/include/string.h
index 36ffc9d..d42e2da 100644
--- a/libc/include/string.h
+++ b/libc/include/string.h
@@ -168,7 +168,7 @@
*
* Returns a pointer to a string, or null for unknown errno values.
*
- * Available since API level 35.
+ * Available since API level 35 when compiling with `_GNU_SOURCE`.
*/
#if defined(__USE_GNU) && __BIONIC_AVAILABILITY_GUARD(35)
const char* _Nullable strerrorname_np(int __errno_value) __INTRODUCED_IN(35);
@@ -180,6 +180,8 @@
* does not localize, this is the same as strerror() on Android.
*
* Returns a pointer to a string.
+ *
+ * Available when compiling with `_GNU_SOURCE`.
*/
#if defined(__USE_GNU)
const char* _Nonnull strerrordesc_np(int __errno_value) __RENAME(strerror);