Depend on PEM_PARsE_C when using test_cas_pem
diff --git a/programs/ssl/ssl_pthread_server.c b/programs/ssl/ssl_pthread_server.c
index e800197..9b35ff4 100644
--- a/programs/ssl/ssl_pthread_server.c
+++ b/programs/ssl/ssl_pthread_server.c
@@ -45,7 +45,8 @@
     defined(POLARSSL_SSL_SRV_C) && defined(POLARSSL_NET_C) && \
     defined(POLARSSL_RSA_C) && defined(POLARSSL_CTR_DRBG_C) && \
     defined(POLARSSL_X509_CRT_PARSE_C) && defined(POLARSSL_FS_IO) && \
-    defined(POLARSSL_THREADING_C) && defined(POLARSSL_THREADING_PTHREAD)
+    defined(POLARSSL_THREADING_C) && defined(POLARSSL_THREADING_PTHREAD) && \
+    defined(POLARSSL_PEM_PARSE_C)
 #include "mbedtls/entropy.h"
 #include "mbedtls/ctr_drbg.h"
 #include "mbedtls/certs.h"
@@ -81,7 +82,8 @@
     !defined(POLARSSL_SSL_SRV_C) || !defined(POLARSSL_NET_C) ||             \
     !defined(POLARSSL_RSA_C) || !defined(POLARSSL_CTR_DRBG_C) ||            \
     !defined(POLARSSL_X509_CRT_PARSE_C) || !defined(POLARSSL_FS_IO) ||      \
-    !defined(POLARSSL_THREADING_C) || !defined(POLARSSL_THREADING_PTHREAD)
+    !defined(POLARSSL_THREADING_C) || !defined(POLARSSL_THREADING_PTHREAD) || \
+    !defined(POLARSSL_PEM_PARSE_C)
 int main( void )
 {
     polarssl_printf("POLARSSL_BIGNUM_C and/or POLARSSL_CERTS_C and/or POLARSSL_ENTROPY_C "
@@ -89,7 +91,7 @@
            "POLARSSL_NET_C and/or POLARSSL_RSA_C and/or "
            "POLARSSL_CTR_DRBG_C and/or POLARSSL_X509_CRT_PARSE_C and/or "
            "POLARSSL_THREADING_C and/or POLARSSL_THREADING_PTHREAD "
-           "not defined.\n");
+           "and/or POLARSSL_PEM_PARSE_C not defined.\n");
     return( 0 );
 }
 #else