Fix __ASSUME_PREADV and __ASSUME_PWRITEV for Alpha and MicroBlaze (bu…

…g 16649).

Reviewing (for all architectures, with a baseline kernel version of
2.6.32) the kernel support for features for which __ASSUME_* macros
would be affected by a move to 2.6.32 as minimum kernel version showed
up that __ASSUME_PREADV and __ASSUME_PWRITEV were wrongly defined for
MicroBlaze (despite the corresponding syscall table entries not being
wired up in the kernel) and Alpha for 2.6.30 and above (although the
support on Alpha was added in 2.6.33).  This patch makes the
kernel-features.h files undefine those macros for appropriate
versions.

	[BZ #16649]
	* sysdeps/unix/sysv/linux/alpha/kernel-features.h
	[__LINUX_KERNEL_VERSION < 0x020621] (__ASSUME_PREADV): Undefine.
	[__LINUX_KERNEL_VERSION < 0x020621] (__ASSUME_PWRITEV): Likewise.
	* sysdeps/unix/sysv/linux/microblaze/kernel-features.h
	(__ASSUME_PREADV): Undefine.
	(__ASSUME_PWRITEV): Likewise.

ChangeLog

@@ -1,3 +1,13 @@
+2014-03-19  Joseph Myers  <joseph@codesourcery.com>
+
+	[BZ #16649]
+	* sysdeps/unix/sysv/linux/alpha/kernel-features.h
+	[__LINUX_KERNEL_VERSION < 0x020621] (__ASSUME_PREADV): Undefine.
+	[__LINUX_KERNEL_VERSION < 0x020621] (__ASSUME_PWRITEV): Likewise.
+	* sysdeps/unix/sysv/linux/microblaze/kernel-features.h
+	(__ASSUME_PREADV): Undefine.
+	(__ASSUME_PWRITEV): Likewise.
+
 2014-03-18  Roland McGrath  <roland@hack.frob.com>
 
 	* bits/mman-linux.h: Add comment about non-Linux use.

NEWS

@@ -10,8 +10,8 @@ Version 2.20
 * The following bugs are resolved with this release:
 
   15347, 15804, 15894, 16447, 16532, 16545, 16574, 16600, 16609, 16610,
-  16611, 16613, 16623, 16632, 16639, 16642, 16670, 16674, 16677, 16680,
-  16683, 16689, 16695, 16701, 16706, 16707.
+  16611, 16613, 16623, 16632, 16639, 16642, 16649, 16670, 16674, 16677,
+  16680, 16683, 16689, 16695, 16701, 16706, 16707.
 
 * Running the testsuite no longer terminates as soon as a test fails.
   Instead, a file tests.sum (xtests.sum from "make xcheck") is generated,

sysdeps/unix/sysv/linux/alpha/kernel-features.h

@@ -93,4 +93,10 @@
 # define __ASSUME_FDATASYNC	1
 #endif
 
+/* Support for preadv and pwritev was added for alpha in 2.6.33.  */
+#if __LINUX_KERNEL_VERSION < 0x020621
+# undef __ASSUME_PREADV
+# undef __ASSUME_PWRITEV
+#endif
+
 #endif /* _KERNEL_FEATURES_H */

sysdeps/unix/sysv/linux/microblaze/kernel-features.h

@@ -43,5 +43,8 @@
 
 #include_next <kernel-features.h>
 
-/* The MicroBlaze kernel does not support the pselect6 syscall.  */
+/* The MicroBlaze kernel does not support the pselect6, preadv and
+   pwritev syscalls.  */
 #undef __ASSUME_PSELECT
+#undef __ASSUME_PREADV
+#undef __ASSUME_PWRITEV