From af7d9929fab25a2f7029001b194fbe0d2a01207d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marko=20M=C3=A4kel=C3=A4?= <marko.makela@oracle.com>
Date: Wed, 6 Apr 2011 09:22:36 +0300
Subject: [PATCH] Enable __attribute__((cold)) only for GCC 4.3 and later. This
 attribute was introduced in bzr revision-id
 marko.makela@oracle.com-20110405073758-b8y733yvkqum940i and caused older GCC
 versions to emit warnings.

---
 storage/innobase/include/os0thread.h |  2 +-
 storage/innobase/include/univ.i      | 13 +++++++++++++
 storage/innobase/include/ut0dbg.h    |  2 +-
 storage/innobase/include/ut0ut.h     |  2 +-
 4 files changed, 16 insertions(+), 3 deletions(-)

diff --git a/storage/innobase/include/os0thread.h b/storage/innobase/include/os0thread.h
index 0c4acafa7d7..df3cdb7728e 100644
--- a/storage/innobase/include/os0thread.h
+++ b/storage/innobase/include/os0thread.h
@@ -109,7 +109,7 @@ os_thread_exit(
 /*===========*/
 	void*	exit_value)	/*!< in: exit value; in Windows this void*
 				is cast as a DWORD */
-	__attribute__((cold, noreturn));
+	UNIV_COLD __attribute__((noreturn));
 /*****************************************************************//**
 Returns the thread identifier of current thread.
 @return	current thread identifier */
diff --git a/storage/innobase/include/univ.i b/storage/innobase/include/univ.i
index f561226a2de..2c7d32bd1a3 100644
--- a/storage/innobase/include/univ.i
+++ b/storage/innobase/include/univ.i
@@ -255,6 +255,19 @@ easy way to get it to work. See http://bugs.mysql.com/bug.php?id=52263. */
 #else
 # define UNIV_INTERN
 #endif
+#if defined __GNUC__ && (__GNUC__ > 4 || __GNUC__ == 4 && __GNUC_MINOR__ >= 3)
+/** Starting with GCC 4.3, the "cold" attribute is used to inform the
+compiler that a function is unlikely executed.  The function is
+optimized for size rather than speed and on many targets it is placed
+into special subsection of the text section so all cold functions
+appears close together improving code locality of non-cold parts of
+program.  The paths leading to call of cold functions within code are
+marked as unlikely by the branch prediction mechanism.  optimize a
+rarely invoked function for size instead for speed. */
+# define UNIV_COLD __attribute__((cold))
+#else
+# define UNIV_COLD /* empty */
+#endif
 
 #ifndef UNIV_MUST_NOT_INLINE
 /* Definition for inline version */
diff --git a/storage/innobase/include/ut0dbg.h b/storage/innobase/include/ut0dbg.h
index 2cb208a4e9e..07730176d81 100644
--- a/storage/innobase/include/ut0dbg.h
+++ b/storage/innobase/include/ut0dbg.h
@@ -53,7 +53,7 @@ ut_dbg_assertion_failed(
 	const char*	expr,	/*!< in: the failed assertion */
 	const char*	file,	/*!< in: source file containing the assertion */
 	ulint		line)	/*!< in: line number of the assertion */
-	__attribute__((nonnull(2), cold));
+	UNIV_COLD __attribute__((nonnull(2)));
 
 #if defined(__WIN__) || defined(__INTEL_COMPILER)
 # undef UT_DBG_USE_ABORT
diff --git a/storage/innobase/include/ut0ut.h b/storage/innobase/include/ut0ut.h
index fe28a573631..cad39e9a34f 100644
--- a/storage/innobase/include/ut0ut.h
+++ b/storage/innobase/include/ut0ut.h
@@ -276,7 +276,7 @@ void
 ut_print_timestamp(
 /*===============*/
 	FILE*	file)	/*!< in: file where to print */
-	__attribute__((nonnull, cold));
+	UNIV_COLD __attribute__((nonnull));
 /**********************************************************//**
 Sprintfs a timestamp to a buffer, 13..14 chars plus terminating NUL. */
 UNIV_INTERN