ust-fd: Add close_range declaration

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

diff --git a/include/lttng/ust-compiler.h b/include/lttng/ust-compiler.h
index e81246a34b63a2cfb374467e211c93286a749a65..e610f98272ff91a366ce10cc15f99d827276a9a8 100644 (file)
--- a/include/lttng/ust-compiler.h
+++ b/include/lttng/ust-compiler.h
@@ -1,9 +1,7 @@
-/*
- * SPDX-License-Identifier: MIT
- *
- * Copyright (C) 2011-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- * Copyright (C) 2011-2012 Paul Woegerer <paul_woegerer@mentor.com>
- */
+// SPDX-FileCopyrightText: 2011-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+// SPDX-FileCopyrightText: 2011-2012 Paul Woegerer <paul_woegerer@mentor.com>
+//
+// SPDX-License-Identifier: MIT
 
 #ifndef _LTTNG_UST_COMPILER_H
 #define _LTTNG_UST_COMPILER_H
@@ -85,15 +83,17 @@
 /*
  * 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 true, this macro emits a function
+ * prototype with an argument type which is 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.
+ * If the predicate evaluates to false, this macro emits a function
+ * prototype with an argument type which is an array of negative size
+ * which is invalid in C and forces a compiler error. The
+ * c_identifier_msg parameter is used as the argument identifier so it
+ * is printed to the user when the error is reported.
  */
 #define lttng_ust_static_assert(predicate, msg, c_identifier_msg)  \
-    typedef char lttng_ust_static_assert_##c_identifier_msg[2*!!(predicate)-1]
+       void lttng_ust_static_assert_proto(char c_identifier_msg[2*!!(predicate)-1])
 #endif
 
 /* Combine two tokens. */
@@ -103,11 +103,17 @@
                LTTNG_UST_COMPILER__COMBINE_TOKENS(_tokena, _tokenb)
 /*
  * Wrap constructor and destructor functions to invoke them as functions with
- * the constructor/destructor GNU C attributes when building as C, or as the
- * constructor/destructor of a variable defined within an anonymous namespace
- * when building as C++.
+ * the constructor/destructor GNU C attributes, which ensures that those
+ * constructors/destructors are ordered before/after C++
+ * constructors/destructors.
+ *
+ * Wrap constructor and destructor functions as the constructor/destructor of a
+ * variable defined within an anonymous namespace when building as C++ with
+ * LTTNG_UST_ALLOCATE_COMPOUND_LITERAL_ON_HEAP defined. With this option,
+ * there are no guarantees that the events in C++ constructors/destructors will
+ * be traced.
  */
-#ifdef __cplusplus
+#if defined (__cplusplus) && defined (LTTNG_UST_ALLOCATE_COMPOUND_LITERAL_ON_HEAP)
 #define LTTNG_UST_DECLARE_CONSTRUCTOR_DESTRUCTOR(name, constructor_func,       \
                                                 destructor_func, ...)          \
 namespace lttng {                                                              \
@@ -136,7 +142,7 @@ const lttng::ust::details::LTTNG_UST_COMPILER_COMBINE_TOKENS(                       \
        lttng_ust_constructor_destructor_, name)                                \
                LTTNG_UST_COMPILER_COMBINE_TOKENS(name, registration_instance); \
 }
-#else /* __cplusplus */
+#else
 #define LTTNG_UST_DECLARE_CONSTRUCTOR_DESTRUCTOR(name, constructor_func,       \
                                                 destructor_func, ...)          \
        static void LTTNG_UST_COMPILER_COMBINE_TOKENS(lttng_ust_constructor_, name)(void) \