X-Git-Url: http://git.lttng.org./?a=blobdiff_plain;f=include%2Flttng%2Fust-compiler.h;h=e7d72e0da3fd21843b8caa0879200a4c43c38f21;hb=d63241543f82756a2fcdaeb05db54f77e688024c;hp=c35a23e1dfc5aa8b0f1e0e07a931979739116e78;hpb=a8909ba54718ed54cefb1b839a5d41a065df09f9;p=lttng-ust.git

diff --git a/include/lttng/ust-compiler.h b/include/lttng/ust-compiler.h
index c35a23e1..e7d72e0d 100644
--- a/include/lttng/ust-compiler.h
+++ b/include/lttng/ust-compiler.h
@@ -14,8 +14,90 @@
  *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
  */
 
+#include <assert.h>
+
 #define lttng_ust_notrace __attribute__((no_instrument_function))
+#define LTTNG_PACKED	__attribute__((__packed__))
+
+/*
+ * Clang supports the no_sanitize variable attribute on global variables.
+ * GCC only supports the no_sanitize_address function attribute, which is
+ * not what we need.
+ */
+#if defined(__clang__)
+# if __has_feature(address_sanitizer)
+#  define __lttng_ust_variable_attribute_no_sanitize_address \
+	__attribute__((no_sanitize("address")))
+# else
+#  define __lttng_ust_variable_attribute_no_sanitize_address
+# endif
+#else
+#  define __lttng_ust_variable_attribute_no_sanitize_address
+#endif
+
+/*
+ * g++ 4.8 and prior do not support C99 compound literals. Therefore,
+ * force allocating those on the heap with these C++ compilers.
+ */
+#if defined (__cplusplus) && defined (__GNUC__) && \
+	(__GNUC__ < 4) || ((__GNUC__ == 4) && (__GNUC_MINOR__ <= 8))
+# ifndef LTTNG_ALLOCATE_COMPOUND_LITERAL_ON_HEAP
+#  define LTTNG_ALLOCATE_COMPOUND_LITERAL_ON_HEAP
+# endif
+#endif
+
+/*
+ * Compound literals with static storage are needed by LTTng.
+ * Compound literals are part of the C99 and C11 standards, but not
+ * part of the C++ standards. However, those are supported by both g++ and
+ * clang. In order to be strictly C++11 compliant, defining
+ * LTTNG_ALLOCATE_COMPOUND_LITERAL_ON_HEAP before including this header
+ * allocates those on the heap in C++.
+ *
+ * Example use:
+ * static struct mystruct *var = __LTTNG_COMPOUND_LITERAL(struct mystruct, { 1, 2, 3 });
+ */
+#if defined (__cplusplus) && defined (LTTNG_ALLOCATE_COMPOUND_LITERAL_ON_HEAP)
+#define __LTTNG_COMPOUND_LITERAL(type, ...)	new (type) __VA_ARGS__
+#else
+#define __LTTNG_COMPOUND_LITERAL(type, ...)	(type[]) { __VA_ARGS__ }
+#endif
+
+/*
+ * Compile time assertion.
+ * - predicate: boolean expression to evaluate,
+ * - msg: string to print to the user on failure when `static_assert()` is
+ *   supported,
+ * - c_identifier_msg: message to be included in the typedef to emulate a
+ *   static assertion. This parameter must be a valid C identifier as it will
+ *   be used as a typedef name.
+ */
+#if defined (__cplusplus) || __STDC_VERSION__ >= 201112L
+#define lttng_static_assert(predicate, msg, c_identifier_msg)  \
+	static_assert(predicate, msg)
+#else
+/*
+ * Evaluates the predicate and emit a compilation error on failure.
+ *
+ * If the predicate evaluates to true, this macro emits a typedef of an array
+ * of size 0.
+ *
+ * If the predicate evaluates to false, this macro emits a typedef of an array
+ * of negative size which is invalid in C and forces a compiler error. The msg
+ * parameter is used in the tentative typedef so it is printed to the user.
+ */
+#define lttng_static_assert(predicate, msg, c_identifier_msg)  \
+    typedef char lttng_static_assert_##c_identifier_msg[2*!!(predicate)-1];
+#endif
 
 #endif /* _LTTNG_UST_COMPILER_H */