Cleanup: remove redundant memory barrier

[lttng-ust.git] / include / helper.h

diff --git a/include/helper.h b/include/helper.h
index b9448e3324febca1f1923b6ef01c53532529d36c..a187b0e7327b2af0f3d39f1160182ad514317303 100644 (file)
--- a/include/helper.h
+++ b/include/helper.h
@@ -41,4 +41,29 @@ void *zmalloc(size_t len)
                __min1 <= __min2 ? __min1: __min2;      \
        })
 
+#define LTTNG_ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
+
+/*
+ * Use of __builtin_return_address(0) sometimes seems to cause stack
+ * corruption on 32-bit PowerPC. Disable this feature on that
+ * architecture for now by always using the NULL value for the ip
+ * context.
+ */
+#if defined(__PPC__) && !defined(__PPC64__)
+#define LTTNG_UST_CALLER_IP()          NULL
+#else /* #if defined(__PPC__) && !defined(__PPC64__) */
+#define LTTNG_UST_CALLER_IP()          __builtin_return_address(0)
+#endif /* #else #if defined(__PPC__) && !defined(__PPC64__) */
+
+/*
+ * LTTNG_HIDDEN: set the hidden attribute for internal functions
+ * On Windows, symbols are local unless explicitly exported,
+ * see https://gcc.gnu.org/wiki/Visibility
+ */
+#if defined(_WIN32) || defined(__CYGWIN__)
+#define LTTNG_HIDDEN
+#else
+#define LTTNG_HIDDEN __attribute__((visibility("hidden")))
+#endif
+
 #endif /* _LTTNG_UST_HELPER_H */