diff --git a/library/asn1write.c b/library/asn1write.c
index a138d0b..262d0bf 100644
--- a/library/asn1write.c
+++ b/library/asn1write.c
@@ -28,6 +28,7 @@
 #if defined(MBEDTLS_ASN1_WRITE_C)
 
 #include "mbedtls/asn1write.h"
+#include "mbedtls/error.h"
 
 #include <string.h>
 
@@ -131,7 +132,7 @@
 #if defined(MBEDTLS_BIGNUM_C)
 int mbedtls_asn1_write_mpi( unsigned char **p, unsigned char *start, const mbedtls_mpi *X )
 {
-    int ret;
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
     size_t len = 0;
 
     // Write the MPI
@@ -168,7 +169,7 @@
 
 int mbedtls_asn1_write_null( unsigned char **p, unsigned char *start )
 {
-    int ret;
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
     size_t len = 0;
 
     // Write NULL
@@ -182,7 +183,7 @@
 int mbedtls_asn1_write_oid( unsigned char **p, unsigned char *start,
                     const char *oid, size_t oid_len )
 {
-    int ret;
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
     size_t len = 0;
 
     MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_raw_buffer( p, start,
@@ -197,7 +198,7 @@
                                      const char *oid, size_t oid_len,
                                      size_t par_len )
 {
-    int ret;
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
     size_t len = 0;
 
     if( par_len == 0 )
@@ -216,7 +217,7 @@
 
 int mbedtls_asn1_write_bool( unsigned char **p, unsigned char *start, int boolean )
 {
-    int ret;
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
     size_t len = 0;
 
     if( *p - start < 1 )
@@ -233,7 +234,7 @@
 
 int mbedtls_asn1_write_int( unsigned char **p, unsigned char *start, int val )
 {
-    int ret;
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
     size_t len = 0;
 
     do
@@ -263,7 +264,7 @@
 int mbedtls_asn1_write_tagged_string( unsigned char **p, unsigned char *start, int tag,
     const char *text, size_t text_len )
 {
-    int ret;
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
     size_t len = 0;
 
     MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_raw_buffer( p, start,
@@ -339,7 +340,7 @@
 int mbedtls_asn1_write_bitstring( unsigned char **p, unsigned char *start,
                           const unsigned char *buf, size_t bits )
 {
-    int ret;
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
     size_t len = 0;
     size_t unused_bits, byte_len;
 
@@ -372,7 +373,7 @@
 int mbedtls_asn1_write_octet_string( unsigned char **p, unsigned char *start,
                              const unsigned char *buf, size_t size )
 {
-    int ret;
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
     size_t len = 0;
 
     MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_raw_buffer( p, start, buf, size ) );