From: arighi <arighi@38d2e660-2303-0410-9eaa-f027e97ec537>
Date: Wed, 17 Mar 2010 11:53:11 +0000 (+0000)
Subject: Add alignof() macro.
X-Git-Tag: 2.4.0~40
X-Git-Url: https://codewiz.org/gitweb?a=commitdiff_plain;h=07e34b5dabbe1609ff848b2137ccbbff33619144;p=bertos.git

Add alignof() macro.

This macro returns the alignment in memory of a generic data type.

git-svn-id: https://src.develer.com/svnoss/bertos/trunk@3224 38d2e660-2303-0410-9eaa-f027e97ec537
---

diff --git a/bertos/cfg/compiler.h b/bertos/cfg/compiler.h
index 87cdd942..5cacf1dc 100644
--- a/bertos/cfg/compiler.h
+++ b/bertos/cfg/compiler.h
@@ -490,6 +490,16 @@ typedef unsigned char page_t;    /**< Type for banked memory pages. */
 	 */
 	#define countof(a)  (sizeof(a) / sizeof(*(a)))
 #endif
+#ifndef alignof
+	/**
+	 * Return the alignment in memory of a generic data type.
+	 *
+	 * \note We need to worry about alignment when allocating memory that
+	 * will be used later by unknown objects (e.g., malloc()) or, more
+	 * generally, whenever creating generic container types.
+	 */
+	#define alignof(type) offsetof(struct { char c; type member; }, member)
+#endif
 
 /**
  * Cast a member of a structure out to the containing structure.