Move Linux kernel version conditionals to kernel-features.h.

5 files changed, 33 insertions, 10 deletions

diff --git a/ChangeLog b/ChangeLog
index 0edfa16bdc..386f8493c2 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,14 @@
+2012-08-10  Joseph Myers  <joseph@codesourcery.com>
+
+	* sysdeps/unix/sysv/linux/kernel-features.h
+	(__LINUX_ARG_MAX_STACK_BASED_MIN_KERNEL): Define.
+	[__LINUX_KERNEL_VERSION >= __LINUX_ARG_MAX_STACK_BASED_MIN_KERNEL]
+	(__ASSUME_ARG_MAX_STACK_BASED): Define.
+	* sysdeps/unix/sysv/linux/sysconf.c (__sysconf)
+	[__LINUX_KERNEL_VERSION < 0x020617]: Change condition to
+	!__ASSUME_ARG_MAX_STACK_BASED.  Compare version with
+	__LINUX_ARG_MAX_STACK_BASED_MIN_KERNEL.
+
 2012-08-09  Jeff Law <law@redhat.com>
 
 	[BZ #13939]
diff --git a/ports/ChangeLog.ia64 b/ports/ChangeLog.ia64
index 933ac23c2d..943df8d66b 100644
--- a/ports/ChangeLog.ia64
+++ b/ports/ChangeLog.ia64
@@ -1,3 +1,10 @@
+2012-08-10  Joseph Myers  <joseph@codesourcery.com>
+
+	* sysdeps/unix/sysv/linux/ia64/nptl/dl-sysdep.h
+	(_dl_discover_osversion): Do not condition on
+	__LINUX_KERNEL_VERSION < 0x020617.
+	(HAVE_DL_DISCOVER_OSVERSION): Likewise.
+
 2012-08-03  Mike Frysinger  <vapier@gentoo.org>
 
 	[BZ #12194]
diff --git a/ports/sysdeps/unix/sysv/linux/ia64/nptl/dl-sysdep.h b/ports/sysdeps/unix/sysv/linux/ia64/nptl/dl-sysdep.h
index e30e33d2bc..0962129b1f 100644
--- a/ports/sysdeps/unix/sysv/linux/ia64/nptl/dl-sysdep.h
+++ b/ports/sysdeps/unix/sysv/linux/ia64/nptl/dl-sysdep.h
@@ -1,5 +1,5 @@
 /* System-specific settings for dynamic linker code.  IA-64 version.
-   Copyright (C) 2003, 2004, 2006, 2008 Free Software Foundation, Inc.
+   Copyright (C) 2003-2012 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -65,9 +65,7 @@ extern int _dl_sysinfo_break attribute_hidden;
 #define DL_ARGV_NOT_RELRO 1
 
 
-/* The _dl_discover_osversion function is so far only needed in sysconf
-   to check for kernels later than 2.6.23.  */
-#if !defined __ASSEMBLER__ && __LINUX_KERNEL_VERSION < 0x020617
+#ifndef __ASSEMBLER__
 /* Get version of the OS.  */
 extern int _dl_discover_osversion (void) attribute_hidden;
 # define HAVE_DL_DISCOVER_OSVERSION	1
diff --git a/sysdeps/unix/sysv/linux/kernel-features.h b/sysdeps/unix/sysv/linux/kernel-features.h
index 21fba884e8..bf81c4a07f 100644
--- a/sysdeps/unix/sysv/linux/kernel-features.h
+++ b/sysdeps/unix/sysv/linux/kernel-features.h
@@ -210,6 +210,13 @@
 # define __ASSUME_O_CLOEXEC	1
 #endif
 
+/* From 2.6.23 onwards the value of ARG_MAX depends on the stack
+   size.  */
+#define __LINUX_ARG_MAX_STACK_BASED_MIN_KERNEL	0x020617
+#if __LINUX_KERNEL_VERSION >= __LINUX_ARG_MAX_STACK_BASED_MIN_KERNEL
+# define __ASSUME_ARG_MAX_STACK_BASED	1
+#endif
+
 /* Support for ADJ_OFFSET_SS_READ was added in 2.6.24.  */
 #if __LINUX_KERNEL_VERSION >= 0x020618
 # define __ASSUME_ADJ_OFFSET_SS_READ	1
diff --git a/sysdeps/unix/sysv/linux/sysconf.c b/sysdeps/unix/sysv/linux/sysconf.c
index 5c8f45d784..47ce5ef07c 100644
--- a/sysdeps/unix/sysv/linux/sysconf.c
+++ b/sysdeps/unix/sysv/linux/sysconf.c
@@ -1,5 +1,5 @@
 /* Get file-specific information about a file.  Linux version.
-   Copyright (C) 2003,2004,2006 2008,2009,2011 Free Software Foundation, Inc.
+   Copyright (C) 2003-2012 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -88,11 +88,11 @@ __sysconf (int name)
       return HAS_CPUCLOCK (name);
 
     case _SC_ARG_MAX:
-#if __LINUX_KERNEL_VERSION < 0x020617
-      /* Determine whether this is a kernel 2.6.23 or later.  Only
-	 then do we have an argument limit determined by the stack
-	 size.  */
-      if (GLRO(dl_discover_osversion) () >= 0x020617)
+#if !__ASSUME_ARG_MAX_STACK_BASED
+      /* Determine whether this is a kernel with an argument limit
+	 determined by the stack size.  */
+      if (GLRO(dl_discover_osversion) ()
+	  >= __LINUX_ARG_MAX_STACK_BASED_MIN_KERNEL)
 #endif
 	/* Use getrlimit to get the stack limit.  */
 	if (__getrlimit (RLIMIT_STACK, &rlimit) == 0)