lib: Reset libbabeltrace2 to SONANE 0

[babeltrace.git] / include / babeltrace / assert-internal.h

diff --git a/include/babeltrace/assert-internal.h b/include/babeltrace/assert-internal.h
index c8a9f8377b469b48131cbe41e875d982dd101724..f8fd0b922cf21a57d1f32be9c202deadd54e1dae 100644 (file)
--- a/include/babeltrace/assert-internal.h
+++ b/include/babeltrace/assert-internal.h
@@ -25,22 +25,43 @@
  */
 
 #include <assert.h>
+#include <babeltrace/babeltrace-internal.h>
 
 #ifdef BT_DEBUG_MODE
+
+extern void bt_common_assert_failed(const char *file, int line,
+       const char *func, const char *assertion) __attribute__((noreturn));
+
 /*
  * Internal assertion (to detect logic errors on which the library user
  * has no influence). Use BT_ASSERT_PRE() to check a precondition which
  * must be directly or indirectly satisfied by the library user.
  */
-# define BT_ASSERT(_cond)      do { assert(_cond); } while (0)
+#define BT_ASSERT(_cond)                                                       \
+       do {                                                                   \
+               if (!(_cond)) {                                                \
+                       bt_common_assert_failed(__FILE__, __LINE__, __func__,  \
+                               TOSTRING(_cond));                              \
+               }                                                              \
+       } while (0)
 
 /*
  * Marks a function as being only used within a BT_ASSERT() context.
  */
 # define BT_ASSERT_FUNC
 #else
-# define BT_ASSERT(_cond)
-# define BT_ASSERT_FUNC                __attribute__((unused))
+/*
+ * When BT_DEBUG_MODE is not defined, define BT_ASSERT() macro to the following
+ * to trick the compiler into thinking that the variable passed as condition to
+ * the assertion is used. This is to prevent set-but-not-used warnings from the
+ * compiler when assertions are disabled. The `sizeof` operator also makes sure
+ * that the `_cond` expression is not evaluated, thus preventing unwanted side
+ * effects.
+ *
+ * In-depth explanation: https://stackoverflow.com/questions/37411809/how-to-elegantly-fix-this-unused-variable-warning/37412551#37412551
+ */
+# define BT_ASSERT(_cond)      ((void) sizeof((void) (_cond), 0))
+# define BT_ASSERT_FUNC                BT_UNUSED
 #endif /* BT_DEBUG_MODE */
 
 #endif /* BABELTRACE_ASSERT_INTERNAL_H */