build: allow building with latest xfslibs on 32-bit Linux

The next version of xfslibs will require that its users enable
transparent largefile support.  This broke building xfstests on
32-bit Linux because _FILE_OFFSET_BITS=64 was not getting defined
when testing for xfs headers.  Fix this by defining
_FILE_OFFSET_BITS=64 when doing configure checks for the xfs
headers.

It was not necessary to define _FILE_OFFSET_BITS=64 for the actual
build because it's already done, in builddefs.in.

The problem could also be solved by adding AC_SYS_LARGEFILE to
configure.ac.  It's debatable, but I chose not to do that because it
might give the impression that it affects the actual compilation of
the test programs and not just the configure checks.  (Since not all
.c files include config.h first, a _FILE_OFFSET_BITS definition in
config.h wouldn't always take effect.)

Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Eryu Guan <eguan@redhat.com>
Signed-off-by: Eryu Guan <eguan@redhat.com>

diff --git a/m4/package_xfslibs.m4 b/m4/package_xfslibs.m4
index 6bf47040d91b0749e185275265dd7796317cddb9..5588e9ed573d910460145e45986bf9565f1a7dd4 100644 (file)
--- a/m4/package_xfslibs.m4
+++ b/m4/package_xfslibs.m4
@@ -1,5 +1,8 @@
 AC_DEFUN([AC_PACKAGE_NEED_XFS_XFS_H],
-  [ AC_CHECK_HEADERS([xfs/xfs.h],,,[#define _GNU_SOURCE])
+  [ AC_CHECK_HEADERS([xfs/xfs.h],,,[
+      #define _GNU_SOURCE
+      #define _FILE_OFFSET_BITS 64
+    ])
     if test "$ac_cv_header_xfs_xfs_h" != "yes"; then
         echo
         echo 'FATAL ERROR: cannot find a valid <xfs/xfs.h> header file.'
@@ -23,7 +26,10 @@ AC_DEFUN([AC_PACKAGE_WANT_XLOG_ASSIGN_LSN],
   ])
 
 AC_DEFUN([AC_PACKAGE_NEED_XFS_XQM_H],
-  [ AC_CHECK_HEADERS([xfs/xqm.h],,,[#define _GNU_SOURCE])
+  [ AC_CHECK_HEADERS([xfs/xqm.h],,,[
+        #define _GNU_SOURCE
+        #define _FILE_OFFSET_BITS 64
+    ])
     if test "$ac_cv_header_xfs_xqm_h" != "yes"; then
         echo
         echo 'FATAL ERROR: cannot find a valid <xfs/xqm.h> header file.'
@@ -103,6 +109,7 @@ AC_DEFUN([AC_PACKAGE_NEED_XFSCTL_MACRO],
   [ AC_MSG_CHECKING([xfsctl from xfs/xfs.h])
     AC_TRY_LINK([
 #define _GNU_SOURCE
+#define _FILE_OFFSET_BITS 64
 #include <xfs/xfs.h> ],
       [ int x = xfsctl(0, 0, 0, 0); ],
       [ echo ok ],