Merge pull request #3113 from geky/static-assert

Add static assert macro

TESTS/mbedmicro-mbed/static_assert/main.cpp

@@ -0,0 +1,26 @@
+#include <stdio.h>
+#include <stdint.h>
+
+#include "toolchain.h"
+#include "greentea-client/test_env.h"
+#include "unity.h"
+#include "utest.h"
+
+using namespace utest::v1;
+
+void no_test() {}
+
+utest::v1::status_t test_setup(const size_t number_of_cases) {
+    GREENTEA_SETUP(5, "default_auto");
+    return verbose_test_setup_handler(number_of_cases);
+}
+
+Case cases[] = {
+    Case("Compilation test", no_test),
+};
+
+Specification specification(test_setup, cases);
+
+int main() {
+    return !Harness::run(specification);
+}

TESTS/mbedmicro-mbed/static_assert/test_c.c

@@ -0,0 +1,39 @@
+#include "mbed_assert.h"
+#define THE_ANSWER 42
+
+// Tests for static asserts in different contexts
+// multiple asserts are used to garuntee no conflicts occur in generated labels
+
+// Test for static asserts in global context
+MBED_STATIC_ASSERT(sizeof(int) >= sizeof(char),
+        "An int must be larger than char");
+MBED_STATIC_ASSERT(2 + 2 == 4,
+        "Hopefully the universe is mathematically consistent");
+MBED_STATIC_ASSERT(THE_ANSWER == 42,
+        "Said Deep Thought, with infinite majesty and calm");
+
+struct test {
+    int dummy;
+
+    // Test for static asserts in struct context
+    MBED_STRUCT_STATIC_ASSERT(sizeof(int) >= sizeof(char),
+            "An int must be larger than char");
+    MBED_STRUCT_STATIC_ASSERT(2 + 2 == 4,
+            "Hopefully the universe is mathematically consistent");
+    MBED_STRUCT_STATIC_ASSERT(THE_ANSWER == 42,
+            "Said Deep Thought, with infinite majesty and calm");
+};
+
+MBED_STATIC_ASSERT(sizeof(struct test) == sizeof(int),
+        "Static assertions should not change the size of a struct");
+
+void doit_c(void) {
+    // Test for static asserts in function context
+    MBED_STATIC_ASSERT(sizeof(int) >= sizeof(char),
+            "An int must be larger than char");
+    MBED_STATIC_ASSERT(2 + 2 == 4,
+            "Hopefully the universe is mathematically consistent");
+    MBED_STATIC_ASSERT(THE_ANSWER == 42,
+            "Said Deep Thought, with infinite majesty and calm");
+}
+

TESTS/mbedmicro-mbed/static_assert/test_cpp.cpp

@@ -0,0 +1,46 @@
+#include "mbed_assert.h"
+#define THE_ANSWER 42
+
+// Tests for static asserts in different contexts
+// multiple asserts are used to garuntee no conflicts occur in generated labels
+
+// Test for static asserts in global context
+MBED_STATIC_ASSERT(sizeof(int) >= sizeof(char),
+        "An int must be larger than char");
+MBED_STATIC_ASSERT(2 + 2 == 4,
+        "Hopefully the universe is mathematically consistent");
+MBED_STATIC_ASSERT(THE_ANSWER == 42,
+        "Said Deep Thought, with infinite majesty and calm");
+
+struct test {
+    int dummy;
+
+    // Test for static asserts in struct context
+    MBED_STRUCT_STATIC_ASSERT(sizeof(int) >= sizeof(char),
+            "An int must be larger than char");
+    MBED_STRUCT_STATIC_ASSERT(2 + 2 == 4,
+            "Hopefully the universe is mathematically consistent");
+    MBED_STRUCT_STATIC_ASSERT(THE_ANSWER == 42,
+            "Said Deep Thought, with infinite majesty and calm");
+
+    MBED_STATIC_ASSERT(sizeof(int) >= sizeof(char),
+            "An int must be larger than char");
+    MBED_STATIC_ASSERT(2 + 2 == 4,
+            "Hopefully the universe is mathematically consistent");
+    MBED_STATIC_ASSERT(THE_ANSWER == 42,
+            "Said Deep Thought, with infinite majesty and calm");
+};
+
+MBED_STATIC_ASSERT(sizeof(struct test) == sizeof(int),
+        "Static assertions should not change the size of a struct");
+
+void doit_c(void) {
+    // Test for static asserts in function context
+    MBED_STATIC_ASSERT(sizeof(int) >= sizeof(char),
+            "An int must be larger than char");
+    MBED_STATIC_ASSERT(2 + 2 == 4,
+            "Hopefully the universe is mathematically consistent");
+    MBED_STATIC_ASSERT(THE_ANSWER == 42,
+            "Said Deep Thought, with infinite majesty and calm");
+}
+

events/equeue/equeue_mbed.cpp

@@ -38,8 +38,10 @@ static void equeue_tick_update() {
 }
 
 static void equeue_tick_init() {
-    MBED_ASSERT(sizeof(equeue_timer) >= sizeof(Timer));
-    MBED_ASSERT(sizeof(equeue_ticker) >= sizeof(Ticker));
+    MBED_STATIC_ASSERT(sizeof(equeue_timer) >= sizeof(Timer),
+            "The equeue_timer buffer must fit the class Timer");
+    MBED_STATIC_ASSERT(sizeof(equeue_ticker) >= sizeof(Ticker),
+            "The equeue_ticker buffer must fit the class Ticker");
     new (equeue_timer) Timer;
     new (equeue_ticker) Ticker;
 
@@ -78,7 +80,8 @@ void equeue_mutex_unlock(equeue_mutex_t *m) {
 #ifdef MBED_CONF_RTOS_PRESENT
 
 int equeue_sema_create(equeue_sema_t *s) {
-    MBED_ASSERT(sizeof(equeue_sema_t) >= sizeof(Semaphore));
+    MBED_STATIC_ASSERT(sizeof(equeue_sema_t) >= sizeof(Semaphore),
+            "The equeue_sema_t must fit the class Semaphore");
     new (s) Semaphore(0);
     return 0;
 }

features/netsocket/NetworkStack.cpp

@@ -281,7 +281,8 @@ protected:
 // Conversion function for network stacks
 NetworkStack *nsapi_create_stack(nsapi_stack_t *stack)
 {
-    MBED_ASSERT(sizeof stack->_stack_buffer >= sizeof(NetworkStackWrapper));
+    MBED_STATIC_ASSERT(sizeof stack->_stack_buffer >= sizeof(NetworkStackWrapper),
+            "The nsapi_stack_t stack buffer must fit a NetworkStackWrapper");
     return new (stack->_stack_buffer) NetworkStackWrapper;
 }
 

platform/Callback.h

@@ -715,7 +715,8 @@ private:
             &Callback::function_dtor<F>,
         };
 
-        MBED_ASSERT(sizeof(Callback) - sizeof(_ops) >= sizeof(F));
+        MBED_STATIC_ASSERT(sizeof(Callback) - sizeof(_ops) >= sizeof(F),
+                "Type F must not exceed the size of the Callback class");
         new (this) F(f);
         _ops = &ops;
     }
@@ -1421,7 +1422,8 @@ private:
             &Callback::function_dtor<F>,
         };
 
-        MBED_ASSERT(sizeof(Callback) - sizeof(_ops) >= sizeof(F));
+        MBED_STATIC_ASSERT(sizeof(Callback) - sizeof(_ops) >= sizeof(F),
+                "Type F must not exceed the size of the Callback class");
         new (this) F(f);
         _ops = &ops;
     }
@@ -2127,7 +2129,8 @@ private:
             &Callback::function_dtor<F>,
         };
 
-        MBED_ASSERT(sizeof(Callback) - sizeof(_ops) >= sizeof(F));
+        MBED_STATIC_ASSERT(sizeof(Callback) - sizeof(_ops) >= sizeof(F),
+                "Type F must not exceed the size of the Callback class");
         new (this) F(f);
         _ops = &ops;
     }
@@ -2833,7 +2836,8 @@ private:
             &Callback::function_dtor<F>,
         };
 
-        MBED_ASSERT(sizeof(Callback) - sizeof(_ops) >= sizeof(F));
+        MBED_STATIC_ASSERT(sizeof(Callback) - sizeof(_ops) >= sizeof(F),
+                "Type F must not exceed the size of the Callback class");
         new (this) F(f);
         _ops = &ops;
     }
@@ -3539,7 +3543,8 @@ private:
             &Callback::function_dtor<F>,
         };
 
-        MBED_ASSERT(sizeof(Callback) - sizeof(_ops) >= sizeof(F));
+        MBED_STATIC_ASSERT(sizeof(Callback) - sizeof(_ops) >= sizeof(F),
+                "Type F must not exceed the size of the Callback class");
         new (this) F(f);
         _ops = &ops;
     }
@@ -4245,7 +4250,8 @@ private:
             &Callback::function_dtor<F>,
         };
 
-        MBED_ASSERT(sizeof(Callback) - sizeof(_ops) >= sizeof(F));
+        MBED_STATIC_ASSERT(sizeof(Callback) - sizeof(_ops) >= sizeof(F),
+                "Type F must not exceed the size of the Callback class");
         new (this) F(f);
         _ops = &ops;
     }

platform/mbed_assert.h

@@ -19,6 +19,8 @@
 #ifndef MBED_ASSERT_H
 #define MBED_ASSERT_H
 
+#include "mbed_preprocessor.h"
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -49,6 +51,63 @@ do {                                                     \
 } while (0)
 #endif
 
+
+/** MBED_STATIC_ASSERT
+ *  Declare compile-time assertions, results in compile-time error if condition is false
+ *
+ *  The assertion acts as a declaration that can be placed at file scope, in a
+ *  code block (except after a label), or as a member of a C++ class/struct/union.
+ *
+ *  @note
+ *  Use of MBED_STATIC_ASSERT as a member of a struct/union is limited:
+ *  - In C++, MBED_STATIC_ASSERT is valid in class/struct/union scope.
+ *  - In C, MBED_STATIC_ASSERT is not valid in struct/union scope, and
+ *    MBED_STRUCT_STATIC_ASSERT is provided as an alternative that is valid
+ *    in C and C++ class/struct/union scope.
+ *
+ *  @code
+ *  MBED_STATIC_ASSERT(MBED_LIBRARY_VERSION >= 120,
+ *          "The mbed library must be at least version 120");
+ *
+ *  int main() {
+ *      MBED_STATIC_ASSERT(sizeof(int) >= sizeof(char),
+ *              "An int must be larger than a char");
+ *  }
+ *  @endcode
+ */
+#if defined(__cplusplus) && (__cplusplus >= 201103L || __cpp_static_assert >= 200410L)
+#define MBED_STATIC_ASSERT(expr, msg) static_assert(expr, msg)
+#elif !defined(__cplusplus) && __STDC_VERSION__ >= 201112L
+#define MBED_STATIC_ASSERT(expr, msg) _Static_assert(expr, msg)
+#elif defined(__cplusplus) && defined(__GNUC__) && defined(__GXX_EXPERIMENTAL_CXX0X__) \
+    && (__GNUC__*100 + __GNUC_MINOR__) > 403L
+#define MBED_STATIC_ASSERT(expr, msg) __extension__ static_assert(expr, msg)
+#elif !defined(__cplusplus) && defined(__GNUC__) && !defined(__CC_ARM) \
+    && (__GNUC__*100 + __GNUC_MINOR__) > 406L
+#define MBED_STATIC_ASSERT(expr, msg) __extension__ _Static_assert(expr, msg)
+#elif defined(__ICCARM__)
+#define MBED_STATIC_ASSERT(expr, msg) static_assert(expr, msg)
+#else
+#define MBED_STATIC_ASSERT(expr, msg) \
+    enum {MBED_CONCAT(MBED_ASSERTION_AT_, __LINE__) = sizeof(char[(expr) ? 1 : -1])}
+#endif
+
+/** MBED_STRUCT_STATIC_ASSERT
+ *  Declare compile-time assertions, results in compile-time error if condition is false
+ *
+ *  Unlike MBED_STATIC_ASSERT, MBED_STRUCT_STATIC_ASSERT can and must be used
+ *  as a member of a C/C++ class/struct/union.
+ *
+ *  @code
+ *  struct thing {
+ *      MBED_STATIC_ASSERT(2 + 2 == 4,
+ *              "Hopefully the universe is mathematically consistent");
+ *  };
+ *  @endcode
+ */
+#define MBED_STRUCT_STATIC_ASSERT(expr, msg) int : (expr) ? 0 : -1
+
+
 #endif
 
 /** @}*/

platform/mbed_preprocessor.h

@@ -0,0 +1,53 @@
+/** \addtogroup platform */
+/** @{*/
+/* mbed Microcontroller Library
+ * Copyright (c) 2006-2013 ARM Limited
+ *
+ * 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.
+ */
+#ifndef MBED_PREPROCESSOR_H
+#define MBED_PREPROCESSOR_H
+
+
+/** MBED_CONCAT
+ *  Concatenate tokens together
+ *
+ *  @note
+ *  Expands tokens before concatenation
+ *
+ *  @code
+ *  // Creates a unique label based on the line number
+ *  int MBED_CONCAT(UNIQUE_LABEL_, __LINE__) = 1;
+ *  @endcode
+ */
+#define MBED_CONCAT(a, b) MBED_CONCAT_(a, b)
+#define MBED_CONCAT_(a, b) a##b
+
+/** MBED_STRINGIFY
+ *  Converts tokens into strings
+ *
+ *  @note
+ *  Expands tokens before stringification
+ *
+ *  @code
+ *  // Creates a string based on the parameters
+ *  const char *c = MBED_STRINGIFY(This is a ridiculous way to create a string)
+ *  @endcode
+ */
+#define MBED_STRINGIFY(a) MBED_STRINGIFY_(a)
+#define MBED_STRINGIFY_(a) #a
+
+
+#endif
+
+/** @}*/

platform/toolchain.h

@@ -19,6 +19,8 @@
 #ifndef MBED_TOOLCHAIN_H
 #define MBED_TOOLCHAIN_H
 
+#include "mbed_preprocessor.h"
+
 
 // Warning for unsupported compilers
 #if !defined(__GNUC__)   /* GCC        */ \
@@ -65,8 +67,7 @@
  */
 #ifndef MBED_ALIGN
 #if defined(__ICCARM__)
-#define _MBED_ALIGN(N) _Pragma(#N)
-#define MBED_ALIGN(N) _MBED_ALIGN(data_alignment=N)
+#define MBED_ALIGN(N) _Pragma(MBED_STRINGIFY(data_alignment=N))
 #else
 #define MBED_ALIGN(N) __attribute__((aligned(N)))
 #endif