diff --git a/src/libsodium/include/sodium/utils.h b/src/libsodium/include/sodium/utils.h
index 2ef22777..e3c34800 100644
--- a/src/libsodium/include/sodium/utils.h
+++ b/src/libsodium/include/sodium/utils.h
@@ -93,7 +93,7 @@ int sodium_base642bin(unsigned char *const bin, const size_t bin_maxlen, const c
                       const char **const b64_end, const int variant) __attribute__((nonnull(1)));
 
 SODIUM_EXPORT
-int sodium_ip2bin(unsigned char bin[16], const char *ip, size_t ip_len)
+int sodium_ip2bin(unsigned char bin[16], const char *ip, size_t ip_len_)
     __attribute__((warn_unused_result)) __attribute__((nonnull));
 
 SODIUM_EXPORT
diff --git a/src/libsodium/sodium/codecs.c b/src/libsodium/sodium/codecs.c
index 720a1fd9..600fee9d 100644
--- a/src/libsodium/sodium/codecs.c
+++ b/src/libsodium/sodium/codecs.c
@@ -476,9 +476,10 @@ parse_ipv6(const char *src, const char *end, unsigned char out[16])
 }
 
 int
-sodium_ip2bin(unsigned char bin[16], const char *ip, size_t ip_len)
+sodium_ip2bin(unsigned char bin[16], const char *ip,
+              size_t ip_len_) /* Some AIX versions define a macro named "ip_len" */
 {
-    const char   *ip_end = ip + ip_len;
+    const char   *ip_end = ip + ip_len_;
     const char   *end;
     const char   *z;
     unsigned char v4[4];