Subject: glibc 2.26 refuses to run on CentOS 6.8

From: Ricardo Wurmus <[email-masked]>
Date: Mon, 19 Feb 2018 19:46:02 +0100

Hi Guix,

I have a bad day.  After the upgrade to glibc 2.26 none of the
Guix-installed software runs on the HPC cluster running CentOS 6.8.

The glibc 2.26 expects a minimum kernel version of 3.x on x86_64, but
CentOS 6.8 only comes with a heavily patched 2.6.32.

The NixOS developers patch glibc to make sure that all software still
runs on Linux 2.6.32:

    https://raw.githubusercontent.com/NixOS/nixpkgs/master/pkgs/development/libraries/glibc/allow-kernel-2.6.32.patch

Can we please also apply this?  Without this Guix on HPC is pretty much
dead at the MDC.

diff --git a/sysdeps/unix/sysv/linux/configure b/sysdeps/unix/sysv/linux/configure
index cace758c01..38fe7fe0b0 100644
--- a/sysdeps/unix/sysv/linux/configure
+++ b/sysdeps/unix/sysv/linux/configure
@@ -69,7 +69,7 @@ fi
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking for kernel header at least $minimum_kernel" >&5
 $as_echo_n "checking for kernel header at least $minimum_kernel... " >&6; }
 decnum=`echo "$minimum_kernel.0.0.0" | sed 's/\([0-9]*\)\.\([0-9]*\)\.\([0-9]*\).*/(\1 * 65536 + \2 * 256 + \3)/'`;
-abinum=`echo "$minimum_kernel.0.0.0" | sed 's/\([0-9]*\)\.\([0-9]*\)\.\([0-9]*\).*/\1,\2,\3/'`;
+abinum=`echo "2.6.32.0.0.0" | sed 's/\([0-9]*\)\.\([0-9]*\)\.\([0-9]*\).*/\1,\2,\3/'`;
 cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 #include <linux/version.h>
diff --git a/sysdeps/unix/sysv/linux/configure.ac b/sysdeps/unix/sysv/linux/configure.ac
index 13abda0a51..6abc12eaed 100644
--- a/sysdeps/unix/sysv/linux/configure.ac
+++ b/sysdeps/unix/sysv/linux/configure.ac
@@ -50,7 +50,7 @@ fi
 AC_MSG_CHECKING(for kernel header at least $minimum_kernel)
 changequote(,)dnl
 decnum=`echo "$minimum_kernel.0.0.0" | sed 's/\([0-9]*\)\.\([0-9]*\)\.\([0-9]*\).*/(\1 * 65536 + \2 * 256 + \3)/'`;
-abinum=`echo "$minimum_kernel.0.0.0" | sed 's/\([0-9]*\)\.\([0-9]*\)\.\([0-9]*\).*/\1,\2,\3/'`;
+abinum=`echo "2.6.32.0.0.0" | sed 's/\([0-9]*\)\.\([0-9]*\)\.\([0-9]*\).*/\1,\2,\3/'`;
 changequote([,])dnl
 AC_TRY_COMPILE([#include <linux/version.h>
 #if LINUX_VERSION_CODE < $decnum
diff --git a/sysdeps/unix/sysv/linux/dl-osinfo.h b/sysdeps/unix/sysv/linux/dl-osinfo.h
index 823cd8224d..482caaeeec 100644
--- a/sysdeps/unix/sysv/linux/dl-osinfo.h
+++ b/sysdeps/unix/sysv/linux/dl-osinfo.h
@@ -39,7 +39,7 @@
 	  GLRO(dl_osversion) = version;					      \
 									      \
 	/* Now we can test with the required version.  */		      \
-	if (__LINUX_KERNEL_VERSION > 0 && version < __LINUX_KERNEL_VERSION)   \
+	if (__LINUX_KERNEL_VERSION > 0 && version < __LINUX_KERNEL_VERSION && version != 0x020620)   \
 	  /* Not sufficent.  */						      \
 	  FATAL ("FATAL: kernel too old\n");				      \
       }									      \

--
Ricardo