diff --git a/lang/c/docs/index.txt b/lang/c/docs/index.txt
index df16f9d9678..86f67bc8f96 100644
--- a/lang/c/docs/index.txt
+++ b/lang/c/docs/index.txt
@@ -117,7 +117,7 @@ This section provides an overview of the methods that you can call on an
 interface, but not all of them make sense for all Avro schema types.
 For instance, you won't be able to call +avro_value_set_boolean+ on an
 Avro array value.  If you try to call an inappropriate method, we'll
-return an +EINVAL+ error code.
+return an +EINVAL+/+AVRO_INVALID+ error code.
 
 Note that the functions in this section apply to _all_ Avro values,
 regardless of which value implementation is used under the covers.  This
diff --git a/lang/c/src/avro/basics.h b/lang/c/src/avro/basics.h
index 368509b90c8..62c899c691a 100644
--- a/lang/c/src/avro/basics.h
+++ b/lang/c/src/avro/basics.h
@@ -24,6 +24,7 @@ extern "C" {
 #define CLOSE_EXTERN
 #endif
 
+#include <errno.h>
 
 enum avro_type_t {
 	AVRO_STRING,
@@ -40,7 +41,8 @@ enum avro_type_t {
 	AVRO_MAP,
 	AVRO_ARRAY,
 	AVRO_UNION,
-	AVRO_LINK
+	AVRO_LINK,
+	AVRO_INVALID = EINVAL,
 };
 typedef enum avro_type_t avro_type_t;
 
diff --git a/lang/c/src/consume-binary.c b/lang/c/src/consume-binary.c
index 9f92799d888..5e1db20684f 100644
--- a/lang/c/src/consume-binary.c
+++ b/lang/c/src/consume-binary.c
@@ -322,6 +322,9 @@ avro_consume_binary(avro_reader_t reader, avro_consumer_t *consumer, void *ud)
 	case AVRO_LINK:
 		avro_set_error("Consumer can't consume a link schema directly");
 		return EINVAL;
+	case AVRO_INVALID:
+		avro_set_error("Consumer can't consume an invalid schema");
+		return EINVAL;
 	}
 
 	return 0;
diff --git a/lang/c/src/datum.c b/lang/c/src/datum.c
index 2c427809090..53dfa5ca067 100644
--- a/lang/c/src/datum.c
+++ b/lang/c/src/datum.c
@@ -1086,6 +1086,7 @@ static void avro_datum_free(avro_datum_t datum)
 			}
 			break;
 		case AVRO_NULL:
+		case AVRO_INVALID:
 			/* Nothing allocated */
 			break;
 
diff --git a/lang/c/src/datum_equal.c b/lang/c/src/datum_equal.c
index 2ef750f9bf9..3875bea048d 100644
--- a/lang/c/src/datum_equal.c
+++ b/lang/c/src/datum_equal.c
@@ -181,6 +181,12 @@ int avro_datum_equal(const avro_datum_t a, const avro_datum_t b)
 		 * TODO 
 		 */
 		return 0;
+	case AVRO_INVALID:
+		/*
+		 * Invalid datums should not be compared and returning 0
+		 * matches the other error conditions
+		 */
+		return 0;
 	}
 	return 0;
 }
diff --git a/lang/c/src/datum_size.c b/lang/c/src/datum_size.c
index 770cb655f57..be9b98004ef 100644
--- a/lang/c/src/datum_size.c
+++ b/lang/c/src/datum_size.c
@@ -271,6 +271,7 @@ static int64_t size_datum(avro_writer_t writer, const avro_encoding_t * enc,
 				  avro_datum_to_union(datum));
 
 	case AVRO_LINK:
+	case AVRO_INVALID:
 		break;
 	}
 
diff --git a/lang/c/src/datum_skip.c b/lang/c/src/datum_skip.c
index aa51d793468..e0ce561642e 100644
--- a/lang/c/src/datum_skip.c
+++ b/lang/c/src/datum_skip.c
@@ -196,6 +196,9 @@ int avro_skip_data(avro_reader_t reader, avro_schema_t writers_schema)
 		    avro_skip_data(reader,
 				   (avro_schema_to_link(writers_schema))->to);
 		break;
+	case AVRO_INVALID:
+		rval = EINVAL;
+		break;
 	}
 
 	return rval;
diff --git a/lang/c/src/datum_validate.c b/lang/c/src/datum_validate.c
index d15ebdddaad..6167bd63ff6 100644
--- a/lang/c/src/datum_validate.c
+++ b/lang/c/src/datum_validate.c
@@ -188,6 +188,8 @@ avro_schema_datum_validate(avro_schema_t expected_schema, avro_datum_t datum)
 						       datum);
 		}
 		break;
+	case AVRO_INVALID:
+		return EINVAL;
 	}
 	return 0;
 }
diff --git a/lang/c/src/datum_value.c b/lang/c/src/datum_value.c
index a4fa55a0c9e..597d38c45bc 100644
--- a/lang/c/src/datum_value.c
+++ b/lang/c/src/datum_value.c
@@ -80,19 +80,7 @@ avro_datum_value_get_type(const avro_value_iface_t *iface, const void *vself)
 {
 	AVRO_UNUSED(iface);
 	const avro_datum_t  self = (const avro_datum_t) vself;
-#ifdef _WIN32
-#pragma message("#warning: Bug: EINVAL is not of type avro_type_t.")
-#else
-#warning "Bug: EINVAL is not of type avro_type_t."
-#endif
-        /* We shouldn't use EINVAL as the return value to
-         * check_param(), because EINVAL (= 22) is not a valid enum
-         * avro_type_t. This is a structural issue -- we would need a
-         * different interface on all the get_type functions to fix
-         * this. For now, suppressing the error by casting EINVAL to
-         * (avro_type_t) so the code compiles under C++.
-         */
-	check_param((avro_type_t) EINVAL, self, "datum instance");
+	check_param(AVRO_INVALID, self, "datum instance");
 	return avro_typeof(self);
 }
 
diff --git a/lang/c/src/schema.c b/lang/c/src/schema.c
index 7b389002b00..2acad51a13c 100644
--- a/lang/c/src/schema.c
+++ b/lang/c/src/schema.c
@@ -126,6 +126,7 @@ static void avro_schema_free(avro_schema_t schema)
 		case AVRO_DOUBLE:
 		case AVRO_BOOLEAN:
 		case AVRO_NULL:
+		case AVRO_INVALID:
 			/* no memory allocated for primitives */
 			return;
 
@@ -876,15 +877,7 @@ static int
 avro_schema_from_json_t(json_t *json, avro_schema_t *schema,
 			st_table *named_schemas, const char *parent_namespace)
 {
-#ifdef _WIN32
- #pragma message("#warning: Bug: '0' is not of type avro_type_t.")
-#else
- #warning "Bug: '0' is not of type avro_type_t."
-#endif
-  /* We should really have an "AVRO_INVALID" type in
-   * avro_type_t. Suppress warning below in which we set type to 0.
-   */
-	avro_type_t type = (avro_type_t) 0;
+	avro_type_t type = AVRO_INVALID;
 	unsigned int i;
 	avro_schema_t named_type = NULL;
 
@@ -1882,6 +1875,8 @@ avro_schema_to_json2(const avro_schema_t schema, avro_writer_t out,
 		return write_union(out, avro_schema_to_union(schema), parent_namespace);
 	case AVRO_LINK:
 		return write_link(out, avro_schema_to_link(schema), parent_namespace);
+	case AVRO_INVALID:
+		return EINVAL;
 	}
 
 	if (is_avro_primitive(schema)) {
diff --git a/lang/c/tests/CMakeLists.txt b/lang/c/tests/CMakeLists.txt
index 1413a3f376f..3200164770d 100644
--- a/lang/c/tests/CMakeLists.txt
+++ b/lang/c/tests/CMakeLists.txt
@@ -66,6 +66,7 @@ add_avro_test_checkmem(test_data_structures)
 add_avro_test_checkmem(test_avro_schema)
 add_avro_test_checkmem(test_avro_commons_schema)
 add_avro_test_checkmem(test_avro_schema_names)
+add_avro_test_checkmem(test_avro_type_collision)
 add_avro_test_checkmem(test_avro_values)
 add_avro_test_checkmem(test_avro_766)
 add_avro_test_checkmem(test_avro_968)
diff --git a/lang/c/tests/test_avro_type_collision.c b/lang/c/tests/test_avro_type_collision.c
new file mode 100644
index 00000000000..1dda590fd77
--- /dev/null
+++ b/lang/c/tests/test_avro_type_collision.c
@@ -0,0 +1,64 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to you under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ * https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+ * implied.  See the License for the specific language governing
+ * permissions and limitations under the License.
+ */
+
+#include "avro.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#if defined(__GNUC__) || defined(__clang__)
+#pragma GCC diagnostic error "-Wswitch"
+#endif
+
+#define ASSERT_NOT_AVRO_INVALID(type)                                   \
+	if (type == AVRO_INVALID) {                                     \
+		fprintf(stderr, #type " collides with AVRO_INVALID\n"); \
+		exit(EXIT_FAILURE);                                     \
+	} else {                                                        \
+		break;                                                  \
+	}
+
+#define CASE_ASSERTION(type) case type: ASSERT_NOT_AVRO_INVALID(type)
+
+int main(void)
+{
+	avro_schema_t null_schema = avro_schema_null();
+	avro_type_t type = avro_typeof(null_schema);
+	avro_schema_decref(null_schema);
+
+	switch (type) {
+	CASE_ASSERTION(AVRO_STRING)
+	CASE_ASSERTION(AVRO_BYTES)
+	CASE_ASSERTION(AVRO_INT32)
+	CASE_ASSERTION(AVRO_INT64)
+	CASE_ASSERTION(AVRO_FLOAT)
+	CASE_ASSERTION(AVRO_DOUBLE)
+	CASE_ASSERTION(AVRO_BOOLEAN)
+	CASE_ASSERTION(AVRO_NULL)
+	CASE_ASSERTION(AVRO_RECORD)
+	CASE_ASSERTION(AVRO_ENUM)
+	CASE_ASSERTION(AVRO_FIXED)
+	CASE_ASSERTION(AVRO_MAP)
+	CASE_ASSERTION(AVRO_ARRAY)
+	CASE_ASSERTION(AVRO_UNION)
+	CASE_ASSERTION(AVRO_LINK)
+	case AVRO_INVALID:
+		break;
+	}
+
+	return EXIT_SUCCESS;
+}
diff --git a/lang/c/version.sh b/lang/c/version.sh
index be90c0f6329..0481bcc23e5 100755
--- a/lang/c/version.sh
+++ b/lang/c/version.sh
@@ -34,9 +34,9 @@
 #         libavro_binary_age = 0
 #         libavro_interface_age = 0
 #
-libavro_micro_version=23
+libavro_micro_version=24
 libavro_interface_age=0
-libavro_binary_age=0
+libavro_binary_age=1
 
 # IGNORE EVERYTHING ELSE FROM HERE DOWN.........
 if test $# != 1; then