diff --git a/.travis.yml b/.travis.yml
index 1259152..f30a4e3 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -17,6 +17,7 @@
 - tests/ssl-opt.sh -e '\(DTLS\|SCSV\).*openssl'
 - tests/scripts/test-ref-configs.pl
 - tests/scripts/curves.pl
+- tests/scripts/key-exchanges.pl
 env:
   global:
     secure: "barHldniAfXyoWOD/vcO+E6/Xm4fmcaUoC9BeKW+LwsHqlDMLvugaJnmLXkSpkbYhVL61Hzf3bo0KPJn88AFc5Rkf8oYHPjH4adMnVXkf3B9ghHCgznqHsAH3choo6tnPxaFgOwOYmLGb382nQxfE5lUdvnM/W/psQjWt66A1+k="
diff --git a/ChangeLog b/ChangeLog
index fdc66fe..0d4dc64 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -9,6 +9,10 @@
      block. (Potential uses include EAP-TLS and Thread.)
 
 Bugfix
+   * Fix build error with configurations where ECDHE-PSK is the only key
+     exchange. Found and fix provided by Chris Hammond. #270
+   * Fix build error with configurations where RSA, RSA-PSK, ECDH-RSA or
+     ECHD-ECDSA if the only key exchange. Multiple reports. #310
    * Fixed a bug causing some handshakes to fail due to some non-fatal alerts
      not being properly ignored. Found by mancha and Kasom Koht-arsa, #308
    * mbedtls_x509_crt_verify(_with_profile)() now also checks the key type and
diff --git a/include/mbedtls/ssl.h b/include/mbedtls/ssl.h
index cd0505f..810409c 100644
--- a/include/mbedtls/ssl.h
+++ b/include/mbedtls/ssl.h
@@ -55,26 +55,6 @@
 #include <time.h>
 #endif
 
-/* For convenience below and in programs */
-#if defined(MBEDTLS_KEY_EXCHANGE_PSK_ENABLED) ||                           \
-    defined(MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED) ||                       \
-    defined(MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED) ||                       \
-    defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED)
-#define MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED
-#endif
-
-#if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) ||                     \
-    defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) ||                   \
-    defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED)
-#define MBEDTLS_KEY_EXCHANGE__SOME__ECDHE_ENABLED
-#endif
-
-#if defined(MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED) ||                       \
-    defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) ||                     \
-    defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED)
-#define MBEDTLS_KEY_EXCHANGE__SOME__SIGNATURE_ENABLED
-#endif
-
 /*
  * SSL Error codes
  */
@@ -561,7 +541,7 @@
     mbedtls_x509_crl *ca_crl;       /*!< trusted CAs CRLs                   */
 #endif /* MBEDTLS_X509_CRT_PARSE_C */
 
-#if defined(MBEDTLS_KEY_EXCHANGE__SOME__SIGNATURE_ENABLED)
+#if defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED)
     const int *sig_hashes;          /*!< allowed signature hashes           */
 #endif
 
@@ -1627,7 +1607,7 @@
                               const mbedtls_ecp_group_id *curves );
 #endif /* MBEDTLS_ECP_C */
 
-#if defined(MBEDTLS_KEY_EXCHANGE__SOME__SIGNATURE_ENABLED)
+#if defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED)
 /**
  * \brief          Set the allowed hashes for signatures during the handshake.
  *                 (Default: all available hashes.)
@@ -1648,7 +1628,7 @@
  */
 void mbedtls_ssl_conf_sig_hashes( mbedtls_ssl_config *conf,
                                   const int *hashes );
-#endif /* MBEDTLS_KEY_EXCHANGE__SOME__SIGNATURE_ENABLED */
+#endif /* MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED */
 
 #if defined(MBEDTLS_X509_CRT_PARSE_C)
 /**
diff --git a/include/mbedtls/ssl_ciphersuites.h b/include/mbedtls/ssl_ciphersuites.h
index 9cf3f42..deaaa37 100644
--- a/include/mbedtls/ssl_ciphersuites.h
+++ b/include/mbedtls/ssl_ciphersuites.h
@@ -232,7 +232,7 @@
 #define MBEDTLS_TLS_ECJPAKE_WITH_AES_128_CCM_8          0xC0FF  /**< experimental */
 
 /* Reminder: update mbedtls_ssl_premaster_secret when adding a new key exchange.
- * Reminder: update MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED below.
+ * Reminder: update MBEDTLS_KEY_EXCHANGE__xxx below
  */
 typedef enum {
     MBEDTLS_KEY_EXCHANGE_NONE = 0,
@@ -249,17 +249,32 @@
     MBEDTLS_KEY_EXCHANGE_ECJPAKE,
 } mbedtls_key_exchange_type_t;
 
-#if defined(MBEDTLS_KEY_EXCHANGE_RSA_ENABLED)          || \
-    defined(MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED)      || \
-    defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED)    || \
-    defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED)  || \
-    defined(MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED)      || \
-    defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED)    || \
-    defined(MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED)     || \
+/* Key exchanges using a certificate */
+#if defined(MBEDTLS_KEY_EXCHANGE_RSA_ENABLED)           || \
+    defined(MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED)       || \
+    defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED)     || \
+    defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED)   || \
+    defined(MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED)       || \
+    defined(MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED)      || \
     defined(MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED)
 #define MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED
 #endif
 
+/* Key exchanges using a PSK */
+#if defined(MBEDTLS_KEY_EXCHANGE_PSK_ENABLED)           || \
+    defined(MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED)       || \
+    defined(MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED)       || \
+    defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED)
+#define MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED
+#endif
+
+/* Key exchanges using a ECDHE */
+#if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED)     || \
+    defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED)   || \
+    defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED)
+#define MBEDTLS_KEY_EXCHANGE__SOME__ECDHE_ENABLED
+#endif
+
 typedef struct mbedtls_ssl_ciphersuite_t mbedtls_ssl_ciphersuite_t;
 
 #define MBEDTLS_CIPHERSUITE_WEAK       0x01    /**< Weak ciphersuite flag  */
diff --git a/include/mbedtls/ssl_internal.h b/include/mbedtls/ssl_internal.h
index ecfc971..3af059f 100644
--- a/include/mbedtls/ssl_internal.h
+++ b/include/mbedtls/ssl_internal.h
@@ -390,7 +390,7 @@
 int mbedtls_ssl_check_curve( const mbedtls_ssl_context *ssl, mbedtls_ecp_group_id grp_id );
 #endif
 
-#if defined(MBEDTLS_KEY_EXCHANGE__SOME__SIGNATURE_ENABLED)
+#if defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED)
 int mbedtls_ssl_check_sig_hash( const mbedtls_ssl_context *ssl,
                                 mbedtls_md_type_t md );
 #endif
diff --git a/library/ssl_cli.c b/library/ssl_cli.c
index 5d9af17..9663fae 100644
--- a/library/ssl_cli.c
+++ b/library/ssl_cli.c
@@ -2069,7 +2069,9 @@
           MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED */
 
 #if defined(MBEDTLS_SSL_PROTO_TLS1_2)
-#if defined(MBEDTLS_KEY_EXCHANGE__SOME__SIGNATURE_ENABLED)
+#if defined(MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED) ||                       \
+    defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) ||                     \
+    defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED)
 static int ssl_parse_signature_algorithm( mbedtls_ssl_context *ssl,
                                           unsigned char **p,
                                           unsigned char *end,
@@ -2125,7 +2127,9 @@
 
     return( 0 );
 }
-#endif /* MBEDTLS_KEY_EXCHANGE__SOME__SIGNATURE_ENABLED */
+#endif /* MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED ||
+          MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED ||
+          MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED */
 #endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
 
 #if defined(MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED) || \
diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index ef12137..4577849 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -5867,7 +5867,7 @@
 }
 #endif /* MBEDTLS_DHM_C && MBEDTLS_SSL_CLI_C */
 
-#if defined(MBEDTLS_KEY_EXCHANGE__SOME__SIGNATURE_ENABLED)
+#if defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED)
 /*
  * Set allowed/preferred hashes for handshake signatures
  */
@@ -7066,7 +7066,7 @@
     0
 };
 
-#if defined(MBEDTLS_KEY_EXCHANGE__SOME__SIGNATURE_ENABLED)
+#if defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED)
 static int ssl_preset_suiteb_hashes[] = {
     MBEDTLS_MD_SHA256,
     MBEDTLS_MD_SHA384,
@@ -7182,7 +7182,7 @@
             conf->cert_profile = &mbedtls_x509_crt_profile_suiteb;
 #endif
 
-#if defined(MBEDTLS_KEY_EXCHANGE__SOME__SIGNATURE_ENABLED)
+#if defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED)
             conf->sig_hashes = ssl_preset_suiteb_hashes;
 #endif
 
@@ -7215,7 +7215,7 @@
             conf->cert_profile = &mbedtls_x509_crt_profile_default;
 #endif
 
-#if defined(MBEDTLS_KEY_EXCHANGE__SOME__SIGNATURE_ENABLED)
+#if defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED)
             conf->sig_hashes = mbedtls_md_list();
 #endif
 
@@ -7380,7 +7380,7 @@
 }
 #endif /* MBEDTLS_ECP_C */
 
-#if defined(MBEDTLS_KEY_EXCHANGE__SOME__SIGNATURE_ENABLED)
+#if defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED)
 /*
  * Check if a hash proposed by the peer is in our list.
  * Return 0 if we're willing to use it, -1 otherwise.
@@ -7399,7 +7399,7 @@
 
     return( -1 );
 }
-#endif /* MBEDTLS_KEY_EXCHANGE__SOME__SIGNATURE_ENABLED */
+#endif /* MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED */
 
 #if defined(MBEDTLS_X509_CRT_PARSE_C)
 int mbedtls_ssl_check_cert_usage( const mbedtls_x509_crt *cert,
diff --git a/programs/Makefile b/programs/Makefile
index 544a2d8..443689b 100644
--- a/programs/Makefile
+++ b/programs/Makefile
@@ -49,6 +49,7 @@
 	hash/hello$(EXEXT)		hash/generic_sum$(EXEXT)	\
 					pkey/dh_client$(EXEXT)		\
 	pkey/dh_genprime$(EXEXT)	pkey/dh_server$(EXEXT)		\
+	pkey/ecdh_curve25519$(EXEXT)					\
 	pkey/ecdsa$(EXEXT)		pkey/gen_key$(EXEXT)		\
 	pkey/key_app$(EXEXT)		pkey/key_app_writer$(EXEXT)	\
 	pkey/mpi_demo$(EXEXT)		pkey/pk_decrypt$(EXEXT)		\
@@ -112,6 +113,10 @@
 	echo "  CC    pkey/dh_server.c"
 	$(CC) $(LOCAL_CFLAGS) $(CFLAGS) pkey/dh_server.c   $(LOCAL_LDFLAGS) $(LDFLAGS) -o $@
 
+pkey/ecdh_curve25519$(EXEXT): pkey/ecdh_curve25519.c $(DEP)
+	echo "  CC    pkey/ecdh_curve25519.c"
+	$(CC) $(LOCAL_CFLAGS) $(CFLAGS) pkey/ecdh_curve25519.c   $(LOCAL_LDFLAGS) $(LDFLAGS) -o $@
+
 pkey/ecdsa$(EXEXT): pkey/ecdsa.c $(DEP)
 	echo "  CC    pkey/ecdsa.c"
 	$(CC) $(LOCAL_CFLAGS) $(CFLAGS) pkey/ecdsa.c       $(LOCAL_LDFLAGS) $(LDFLAGS) -o $@
diff --git a/programs/pkey/CMakeLists.txt b/programs/pkey/CMakeLists.txt
index 8dc7def..5a37a42 100644
--- a/programs/pkey/CMakeLists.txt
+++ b/programs/pkey/CMakeLists.txt
@@ -7,6 +7,9 @@
 add_executable(dh_server dh_server.c)
 target_link_libraries(dh_server mbedtls)
 
+add_executable(ecdh_curve25519 ecdh_curve25519.c)
+target_link_libraries(ecdh_curve25519 mbedtls)
+
 add_executable(ecdsa ecdsa.c)
 target_link_libraries(ecdsa mbedtls)
 
diff --git a/programs/pkey/ecdh_curve25519.c b/programs/pkey/ecdh_curve25519.c
new file mode 100644
index 0000000..aa15c46
--- /dev/null
+++ b/programs/pkey/ecdh_curve25519.c
@@ -0,0 +1,237 @@
+/*
+ *  Example ECDHE with Curve25519 program
+ *
+ *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
+ *  SPDX-License-Identifier: Apache-2.0
+ *
+ *  Licensed 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
+ *
+ *  http://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.
+ *
+ *  This file is part of mbed TLS (https://tls.mbed.org)
+ */
+
+#if !defined(MBEDTLS_CONFIG_FILE)
+#include "mbedtls/config.h"
+#else
+#include MBEDTLS_CONFIG_FILE
+#endif
+
+#if defined(MBEDTLS_PLATFORM_C)
+#include "mbedtls/platform.h"
+#else
+#include <stdio.h>
+#define mbedtls_printf     printf
+#endif
+
+#if !defined(MBEDTLS_ECDH_C) || \
+    !defined(MBEDTLS_ECP_DP_CURVE25519_ENABLED) || \
+    !defined(MBEDTLS_ENTROPY_C) || !defined(MBEDTLS_CTR_DRBG_C)
+int main( void )
+{
+    mbedtls_printf( "MBEDTLS_ECDH_C and/or "
+                    "MBEDTLS_ECP_DP_CURVE25519_ENABLED and/or "
+                    "MBEDTLS_ENTROPY_C and/or MBEDTLS_CTR_DRBG_C "
+                    "not defined\n" );
+    return( 0 );
+}
+#else
+
+#include "mbedtls/entropy.h"
+#include "mbedtls/ctr_drbg.h"
+#include "mbedtls/ecdh.h"
+
+int main( int argc, char *argv[] )
+{
+    int ret;
+    mbedtls_ecdh_context ctx_cli, ctx_srv;
+    mbedtls_entropy_context entropy;
+    mbedtls_ctr_drbg_context ctr_drbg;
+    unsigned char cli_to_srv[32], srv_to_cli[32];
+    const char pers[] = "ecdh";
+    ((void) argc);
+    ((void) argv);
+
+    mbedtls_ecdh_init( &ctx_cli );
+    mbedtls_ecdh_init( &ctx_srv );
+    mbedtls_ctr_drbg_init( &ctr_drbg );
+
+    /*
+     * Initialize random number generation
+     */
+    mbedtls_printf( "  . Seeding the random number generator..." );
+    fflush( stdout );
+
+    mbedtls_entropy_init( &entropy );
+    if( ( ret = mbedtls_ctr_drbg_seed( &ctr_drbg, mbedtls_entropy_func, &entropy,
+                               (const unsigned char *) pers,
+                               sizeof pers ) ) != 0 )
+    {
+        mbedtls_printf( " failed\n  ! mbedtls_ctr_drbg_seed returned %d\n", ret );
+        goto exit;
+    }
+
+    mbedtls_printf( " ok\n" );
+
+    /*
+     * Client: inialize context and generate keypair
+     */
+    mbedtls_printf( "  . Setting up client context..." );
+    fflush( stdout );
+
+    ret = mbedtls_ecp_group_load( &ctx_cli.grp, MBEDTLS_ECP_DP_CURVE25519 );
+    if( ret != 0 )
+    {
+        mbedtls_printf( " failed\n  ! mbedtls_ecp_group_load returned %d\n", ret );
+        goto exit;
+    }
+
+    ret = mbedtls_ecdh_gen_public( &ctx_cli.grp, &ctx_cli.d, &ctx_cli.Q,
+                                   mbedtls_ctr_drbg_random, &ctr_drbg );
+    if( ret != 0 )
+    {
+        mbedtls_printf( " failed\n  ! mbedtls_ecdh_gen_public returned %d\n", ret );
+        goto exit;
+    }
+
+    ret = mbedtls_mpi_write_binary( &ctx_cli.Q.X, cli_to_srv, 32 );
+    if( ret != 0 )
+    {
+        mbedtls_printf( " failed\n  ! mbedtls_mpi_write_binary returned %d\n", ret );
+        goto exit;
+    }
+
+    mbedtls_printf( " ok\n" );
+
+    /*
+     * Server: initialize context and generate keypair
+     */
+    mbedtls_printf( "  . Setting up server context..." );
+    fflush( stdout );
+
+    ret = mbedtls_ecp_group_load( &ctx_srv.grp, MBEDTLS_ECP_DP_CURVE25519 );
+    if( ret != 0 )
+    {
+        mbedtls_printf( " failed\n  ! mbedtls_ecp_group_load returned %d\n", ret );
+        goto exit;
+    }
+
+    ret = mbedtls_ecdh_gen_public( &ctx_srv.grp, &ctx_srv.d, &ctx_srv.Q,
+                                   mbedtls_ctr_drbg_random, &ctr_drbg );
+    if( ret != 0 )
+    {
+        mbedtls_printf( " failed\n  ! mbedtls_ecdh_gen_public returned %d\n", ret );
+        goto exit;
+    }
+
+    ret = mbedtls_mpi_write_binary( &ctx_srv.Q.X, srv_to_cli, 32 );
+    if( ret != 0 )
+    {
+        mbedtls_printf( " failed\n  ! mbedtls_mpi_write_binary returned %d\n", ret );
+        goto exit;
+    }
+
+    mbedtls_printf( " ok\n" );
+
+    /*
+     * Server: read peer's key and generate shared secret
+     */
+    mbedtls_printf( "  . Server reading client key and computing secret..." );
+    fflush( stdout );
+
+    ret = mbedtls_mpi_lset( &ctx_srv.Qp.Z, 1 );
+    if( ret != 0 )
+    {
+        mbedtls_printf( " failed\n  ! mbedtls_mpi_lset returned %d\n", ret );
+        goto exit;
+    }
+
+    ret = mbedtls_mpi_read_binary( &ctx_srv.Qp.X, cli_to_srv, 32 );
+    if( ret != 0 )
+    {
+        mbedtls_printf( " failed\n  ! mbedtls_mpi_read_binary returned %d\n", ret );
+        goto exit;
+    }
+
+    ret = mbedtls_ecdh_compute_shared( &ctx_srv.grp, &ctx_srv.z,
+                                       &ctx_srv.Qp, &ctx_srv.d,
+                                       mbedtls_ctr_drbg_random, &ctr_drbg );
+    if( ret != 0 )
+    {
+        mbedtls_printf( " failed\n  ! mbedtls_ecdh_compute_shared returned %d\n", ret );
+        goto exit;
+    }
+
+    mbedtls_printf( " ok\n" );
+
+    /*
+     * Client: read peer's key and generate shared secret
+     */
+    mbedtls_printf( "  . Client reading server key and computing secret..." );
+    fflush( stdout );
+
+    ret = mbedtls_mpi_lset( &ctx_cli.Qp.Z, 1 );
+    if( ret != 0 )
+    {
+        mbedtls_printf( " failed\n  ! mbedtls_mpi_lset returned %d\n", ret );
+        goto exit;
+    }
+
+    ret = mbedtls_mpi_read_binary( &ctx_cli.Qp.X, srv_to_cli, 32 );
+    if( ret != 0 )
+    {
+        mbedtls_printf( " failed\n  ! mbedtls_mpi_read_binary returned %d\n", ret );
+        goto exit;
+    }
+
+    ret = mbedtls_ecdh_compute_shared( &ctx_cli.grp, &ctx_cli.z,
+                                       &ctx_cli.Qp, &ctx_cli.d,
+                                       mbedtls_ctr_drbg_random, &ctr_drbg );
+    if( ret != 0 )
+    {
+        mbedtls_printf( " failed\n  ! mbedtls_ecdh_compute_shared returned %d\n", ret );
+        goto exit;
+    }
+
+    mbedtls_printf( " ok\n" );
+
+    /*
+     * Verification: are the computed secret equal?
+     */
+    mbedtls_printf( "  . Checking if both computed secrets are equal..." );
+    fflush( stdout );
+
+    ret = mbedtls_mpi_cmp_mpi( &ctx_cli.z, &ctx_srv.z );
+    if( ret != 0 )
+    {
+        mbedtls_printf( " failed\n  ! mbedtls_ecdh_compute_shared returned %d\n", ret );
+        goto exit;
+    }
+
+    mbedtls_printf( " ok\n" );
+
+
+exit:
+
+#if defined(_WIN32)
+    mbedtls_printf( "  + Press Enter to exit this program.\n" );
+    fflush( stdout ); getchar();
+#endif
+
+    mbedtls_ecdh_free( &ctx_srv );
+    mbedtls_ecdh_free( &ctx_cli );
+    mbedtls_ctr_drbg_free( &ctr_drbg );
+    mbedtls_entropy_free( &entropy );
+
+    return( ret != 0 );
+}
+#endif /* MBEDTLS_ECDH_C && MBEDTLS_ECP_DP_CURVE25519_ENABLED &&
+          MBEDTLS_ENTROPY_C && MBEDTLS_CTR_DRBG_C */
diff --git a/tests/scripts/all.sh b/tests/scripts/all.sh
index 863ff3a..d96615b 100755
--- a/tests/scripts/all.sh
+++ b/tests/scripts/all.sh
@@ -127,11 +127,16 @@
 msg "test: compat.sh RC4, DES & NULL (full config)" # ~ 2 min
 tests/compat.sh -e '3DES\|DES-CBC3' -f 'NULL\|DES\|RC4\|ARCFOUR'
 
-msg "test/build: curves.pl (gcc)" # ~ 5 min (?)
+msg "test/build: curves.pl (gcc)" # ~ 4 min
 cleanup
 cmake -D CMAKE_BUILD_TYPE:String=Debug .
 tests/scripts/curves.pl
 
+msg "test/build: key-exchanges (gcc)" # ~ 1 min
+cleanup
+cmake -D CMAKE_BUILD_TYPE:String=Check .
+tests/scripts/key-exchanges.pl
+
 msg "build: Unix make, -Os (gcc)" # ~ 30s
 cleanup
 CC=gcc CFLAGS='-Werror -Os' make
diff --git a/tests/scripts/key-exchanges.pl b/tests/scripts/key-exchanges.pl
new file mode 100755
index 0000000..46826c3
--- /dev/null
+++ b/tests/scripts/key-exchanges.pl
@@ -0,0 +1,43 @@
+#!/usr/bin/perl
+
+# test that all configs with only a single key exchange enabled build
+#
+# Usage: tests/scripts/key-exchanges.pl
+
+use warnings;
+use strict;
+
+-d 'library' && -d 'include' && -d 'tests' or die "Must be run from root\n";
+
+my $sed_cmd = 's/^#define \(MBEDTLS_KEY_EXCHANGE_.*_ENABLED\)/\1/p';
+my $config_h = 'include/mbedtls/config.h';
+my @kexes = split( /\s+/, `sed -n -e '$sed_cmd' $config_h` );
+
+system( "cp $config_h $config_h.bak" ) and die;
+sub abort {
+    system( "mv $config_h.bak $config_h" ) and warn "$config_h not restored\n";
+    die $_[0];
+}
+
+for my $kex (@kexes) {
+    system( "cp $config_h.bak $config_h" ) and die "$config_h not restored\n";
+    system( "make clean" ) and die;
+
+    print "\n******************************************\n";
+    print "* Testing with key exchange: $kex\n";
+    print "******************************************\n";
+
+    # full config with all key exchanges disabled except one
+    system( "scripts/config.pl full" ) and abort "Failed config full\n";
+    for my $k (@kexes) {
+        next if $k eq $kex;
+        system( "scripts/config.pl unset $k" )
+            and abort "Failed to disable $k\n";
+    }
+
+    system( "make lib CFLAGS='-Os -Werror'" ) and abort "Failed to build lib: $kex\n";
+}
+
+system( "mv $config_h.bak $config_h" ) and die "$config_h not restored\n";
+system( "make clean" ) and die;
+exit 0;
diff --git a/tests/scripts/test-ref-configs.pl b/tests/scripts/test-ref-configs.pl
index b27d64c..8f4738c 100755
--- a/tests/scripts/test-ref-configs.pl
+++ b/tests/scripts/test-ref-configs.pl
@@ -63,7 +63,7 @@
     system( "cp configs/$conf $config_h" )
         and abort "Failed to activate $conf\n";
 
-    system( "make" ) and abort "Failed to build: $conf\n";
+    system( "make CFLAGS='-Os -Werror'" ) and abort "Failed to build: $conf\n";
     system( "make test" ) and abort "Failed test suite: $conf\n";
 
     my $compat = $data->{'compat'};