diff --git a/Doc/c-api/bytes.rst b/Doc/c-api/bytes.rst
index 82c2557368371f..b3cd26a8504715 100644
--- a/Doc/c-api/bytes.rst
+++ b/Doc/c-api/bytes.rst
@@ -371,6 +371,8 @@ Getters
 
    Get the writer size.
 
+   The function cannot fail.
+
 .. c:function:: void* PyBytesWriter_GetData(PyBytesWriter *writer)
 
    Get the writer data: start of the internal buffer.
@@ -378,6 +380,8 @@ Getters
    The pointer is valid until :c:func:`PyBytesWriter_Finish` or
    :c:func:`PyBytesWriter_Discard` is called on *writer*.
 
+   The function cannot fail.
+
 
 Low-level API
 ^^^^^^^^^^^^^
diff --git a/Modules/binascii.c b/Modules/binascii.c
index 3f3695d50f2754..c076b12fb149b2 100644
--- a/Modules/binascii.c
+++ b/Modules/binascii.c
@@ -923,9 +923,6 @@ binascii_a2b_ascii85_impl(PyObject *module, Py_buffer *data, int foldspaces,
         return NULL;
     }
     unsigned char *bin_data = PyBytesWriter_GetData(writer);
-    if (bin_data == NULL) {
-        goto error;
-    }
 
     uint32_t leftchar = 0;
     int group_pos = 0;