Diff: platform/mbed_assert.h

Revision:

151:5eaa88a5bcc7

Parent:

149:156823d33999

--- a/platform/mbed_assert.h	Tue Nov 08 17:45:16 2016 +0000
+++ b/platform/mbed_assert.h	Thu Nov 24 17:03:03 2016 +0000
@@ -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 @@
 } 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
 
 /** @}*/