diff --git a/ChangeLog b/ChangeLog
index 4b7536c33..351275b48 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -6,6 +6,9 @@ Bugfix
    * Fix the redefinition of macro ssl_set_bio to an undefined symbol
      mbedtls_ssl_set_bio_timeout in compat-1.3.h, by removing it.
      Found by omlib-lin. #673
+   * Fix unused variable/function compilation warnings in pem.c, x509_crt.c and
+     x509_csr.c that are reported when building mbed TLS with a config.h that
+     does not define MBEDTLS_PEM_PARSE_C. #562
 
 = mbed TLS 2.4.1 branch released 2016-12-13
 
diff --git a/library/pem.c b/library/pem.c
index 1ee3966e1..b6ad53b7d 100644
--- a/library/pem.c
+++ b/library/pem.c
@@ -44,12 +44,12 @@
 #define mbedtls_free       free
 #endif
 
+#if defined(MBEDTLS_PEM_PARSE_C)
 /* Implementation that should never be optimized out by the compiler */
 static void mbedtls_zeroize( void *v, size_t n ) {
     volatile unsigned char *p = v; while( n-- ) *p++ = 0;
 }
 
-#if defined(MBEDTLS_PEM_PARSE_C)
 void mbedtls_pem_init( mbedtls_pem_context *ctx )
 {
     memset( ctx, 0, sizeof( mbedtls_pem_context ) );
diff --git a/library/x509_crt.c b/library/x509_crt.c
index 80af7259c..056dc16fe 100644
--- a/library/x509_crt.c
+++ b/library/x509_crt.c
@@ -969,8 +969,8 @@ int mbedtls_x509_crt_parse_der( mbedtls_x509_crt *chain, const unsigned char *bu
  */
 int mbedtls_x509_crt_parse( mbedtls_x509_crt *chain, const unsigned char *buf, size_t buflen )
 {
-    int success = 0, first_error = 0, total_failed = 0;
 #if defined(MBEDTLS_PEM_PARSE_C)
+    int success = 0, first_error = 0, total_failed = 0;
     int buf_format = MBEDTLS_X509_FORMAT_DER;
 #endif
 
diff --git a/library/x509_csr.c b/library/x509_csr.c
index 603d06b64..f92b66c58 100644
--- a/library/x509_csr.c
+++ b/library/x509_csr.c
@@ -265,8 +265,8 @@ int mbedtls_x509_csr_parse_der( mbedtls_x509_csr *csr,
  */
 int mbedtls_x509_csr_parse( mbedtls_x509_csr *csr, const unsigned char *buf, size_t buflen )
 {
-    int ret;
 #if defined(MBEDTLS_PEM_PARSE_C)
+    int ret;
     size_t use_len;
     mbedtls_pem_context pem;
 #endif