branches/innodb+: Undo the partial introduction of UNIV_UNUSED, to reduce

differences from branches/zip.  The __attribute__((unused)) should
work on all platforms.  When compiled with something else than GCC,
MySQL supposedly does #define __attribute__(x) /* empty */
so that the attributes will be ignored.

ibuf/ibuf0ibuf.c

@@ -558,7 +558,7 @@ ibuf_parse_bitmap_init(
 /*===================*/
 				/* out: end of log record or NULL */
 	byte*		ptr,	/* in: buffer */
-	byte*		end_ptr UNIV_UNUSED, /* in: buffer end */
+	byte*		end_ptr __attribute__((unused)), /* in: buffer end */
 	buf_block_t*	block,	/* in: block or NULL */
 	mtr_t*		mtr)	/* in: mtr or NULL */
 {
@@ -584,7 +584,7 @@ ibuf_bitmap_page_get_bits(
 				0 for uncompressed pages */
 	ulint		bit,	/* in: IBUF_BITMAP_FREE,
 				IBUF_BITMAP_BUFFERED, ... */
-	mtr_t*		mtr UNIV_UNUSED)
+	mtr_t*		mtr __attribute__((unused)))
 				/* in: mtr containing an
 				x-latch to the bitmap page */
 {

include/btr0btr.ic

@@ -118,7 +118,7 @@ btr_page_get_level(
 /*===============*/
 				/* out: level, leaf level == 0 */
 	const page_t*	page,	/* in: index page */
-	mtr_t*		mtr UNIV_UNUSED)
+	mtr_t*		mtr __attribute__((unused)))
 				/* in: mini-transaction handle */
 {
 	ut_ad(page && mtr);
@@ -160,7 +160,7 @@ btr_page_get_next(
 /*==============*/
 				/* out: next page number */
 	const page_t*	page,	/* in: index page */
-	mtr_t*		mtr UNIV_UNUSED)
+	mtr_t*		mtr __attribute__((unused)))
 				/* in: mini-transaction handle */
 {
 	ut_ad(page && mtr);
@@ -200,7 +200,7 @@ btr_page_get_prev(
 /*==============*/
 				/* out: prev page number */
 	const page_t*	page,	/* in: index page */
-	mtr_t*	mtr     UNIV_UNUSED) /* in: mini-transaction handle */
+	mtr_t*	mtr __attribute__((unused))) /* in: mini-transaction handle */
 {
 	ut_ad(page && mtr);
 

include/univ.i

@@ -340,11 +340,8 @@ it is read. */
 /* Minimize cache-miss latency by moving data at addr into a cache before
 it is read or written. */
 # define UNIV_PREFETCH_RW(addr) __builtin_prefetch(addr, 1, 3)
-/* Tell the compiler that variable/function is unused. */
-# define UNIV_UNUSED    __attribute__ ((unused))
 #else
 /* Dummy versions of the macros */
-# define UNIV_UNUSED
 # define UNIV_EXPECT(expr,value) (expr)
 # define UNIV_LIKELY_NULL(expr) (expr)
 # define UNIV_PREFETCH_R(addr) ((void) 0)