lib/ext/mbedcrypto/0001-BUILD-Update-For-IAR-support.patch

From 8be39b4353bdeee2f80e42c23a73a276cbd9a8ad Mon Sep 17 00:00:00 2001
From: TTornblom <thomas.tornblom@iar.com>
Date: Thu, 16 Apr 2020 13:53:38 +0200
Subject: [PATCH 1/8] BUILD: Update For IAR support

Applied the same change as in mbed-crypto for using this as a sub
project with the IAR toolchain. Use __asm generic ,and avoid empty
enum. Avoid declaration of array with null size.

Signed-off-by: TTornblom <thomas.tornblom@iar.com>
Signed-off-by: Michel Jaouen <michel.jaouen@st.com>
---
 CMakeLists.txt          | 4 +++-
 include/mbedtls/ssl.h   | 1 +
 library/constant_time.c | 2 +-
 library/psa_crypto.c    | 7 ++++++-
 4 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8d3f08a98..096bb6e14 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -222,7 +222,9 @@ if(CMAKE_COMPILER_IS_CLANG)
 endif(CMAKE_COMPILER_IS_CLANG)
 
 if(CMAKE_COMPILER_IS_IAR)
-    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} --warn_about_c_style_casts -Ohz")
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} --warn_about_c_style_casts")
+    set(CMAKE_C_FLAGS_RELEASE     "-Ohz")
+    set(CMAKE_C_FLAGS_DEBUG       "--debug -On")
 endif(CMAKE_COMPILER_IS_IAR)
 
 if(CMAKE_COMPILER_IS_MSVC)
diff --git a/include/mbedtls/ssl.h b/include/mbedtls/ssl.h
index 68e8d040f..fbd150638 100644
--- a/include/mbedtls/ssl.h
+++ b/include/mbedtls/ssl.h
@@ -620,6 +620,7 @@
 
 /* Dummy type used only for its size */
 union mbedtls_ssl_premaster_secret {
+    unsigned MBEDTLS_PRIVATE(dummy); /* Make the union non-empty even with no supported algorithms. */
 #if defined(MBEDTLS_KEY_EXCHANGE_RSA_ENABLED)
     unsigned char _pms_rsa[48];                         /* RFC 5246 8.1.1 */
 #endif
diff --git a/library/constant_time.c b/library/constant_time.c
index 552a918f4..471d91618 100644
--- a/library/constant_time.c
+++ b/library/constant_time.c
@@ -77,7 +77,7 @@ static inline uint32_t mbedtls_get_unaligned_volatile_uint32(volatile const unsi
      */
     uint32_t r;
 #if defined(__arm__) || defined(__thumb__) || defined(__thumb2__)
-    asm volatile ("ldr %0, [%1]" : "=r" (r) : "r" (p) :);
+    __asm volatile ("ldr %0, [%1]" : "=r" (r) : "r" (p) :);
 #elif defined(__aarch64__)
     asm volatile ("ldr %w0, [%1]" : "=r" (r) : "r" (p) :);
 #endif
diff --git a/library/psa_crypto.c b/library/psa_crypto.c
index bc19ed07c..8b9f28f4d 100644
--- a/library/psa_crypto.c
+++ b/library/psa_crypto.c
@@ -6611,8 +6611,13 @@ static psa_status_t psa_key_agreement_internal(psa_key_derivation_operation_t *o
                                                size_t peer_key_length)
 {
     psa_status_t status;
+#if PSA_RAW_KEY_AGREEMENT_OUTPUT_MAX_SIZE != 0
     uint8_t shared_secret[PSA_RAW_KEY_AGREEMENT_OUTPUT_MAX_SIZE];
+    size_t shared_secret_length = sizeof(shared_secret);
+#else
+    uint8_t *shared_secret = NULL;
     size_t shared_secret_length = 0;
+#endif
     psa_algorithm_t ka_alg = PSA_ALG_KEY_AGREEMENT_GET_BASE(operation->alg);
 
     /* Step 1: run the secret agreement algorithm to generate the shared
@@ -6621,7 +6626,7 @@ static psa_status_t psa_key_agreement_internal(psa_key_derivation_operation_t *o
                                             private_key,
                                             peer_key, peer_key_length,
                                             shared_secret,
-                                            sizeof(shared_secret),
+                                            shared_secret_length,
                                             &shared_secret_length);
     if (status != PSA_SUCCESS) {
         goto exit;
-- 
2.32.0