Fix detection of statx.stx_mnt_id on buggy glibc

* https://gitlab.haskell.org/ghc/ghc/-/issues/24072
* https://lore.kernel.org/all/20220223111835.00ef0e83@bahia/T/

Author: hasufell

System/Posix/Files/Common.hsc

@@ -940,7 +940,7 @@ pattern StatxBtime = StatxMask 0
 
 -- | Want @stx_mnt_id@.
 pattern StatxMntId :: StatxMask
-#ifdef STATX_MNT_ID
+#ifdef HAVE_STATX_MNT_ID
 pattern StatxMntId = StatxMask (#const STATX_MNT_ID)
 #else
 pattern StatxMntId = StatxMask 0
@@ -1160,11 +1160,11 @@ specialDeviceIDX (ExtendedFileStatus statx) = unsafePerformIO $ do
 {-# WARNING specialDeviceIDX "specialDeviceIDX: not available on this platform, will throw error (CPP guard: @#if HAVE_SYS_SYSMACROS_H@)" #-}
 specialDeviceIDX _ = error "specialDeviceIDX not available on this platform"
 #endif
-#ifdef STATX_MNT_ID
+#ifdef HAVE_STATX_MNT_ID
 mountIDX (ExtendedFileStatus statx) =
   unsafePerformIO $ withForeignPtr statx $ (#peek struct statx, stx_mnt_id)
 #else
-{-# WARNING mountIDX "mountIDX: not available on this platform, will throw error (CPP guard: @#if STATX_MNT_ID@)" #-}
+{-# WARNING mountIDX "mountIDX: not available on this platform, will throw error (CPP guard: @#if HAVE_STATX_MNT_ID@)" #-}
 mountIDX _ = error "mountIDX not available on this platform"
 #endif
 fileBlockSizeX (ExtendedFileStatus statx) = unsafePerformIO $ do

changelog.md

@@ -3,6 +3,7 @@
 ## 2.8.4.0 *??? 2023*
 
   * add `haveStatx`
+  * fix `statx.stx_mnt_id` detection on buggy glibc, see [GHC #24072](https://gitlab.haskell.org/ghc/ghc/-/issues/24072)
 
 ## 2.8.3.0 *Oct 2023*
 

configure.ac

@@ -50,6 +50,23 @@ AC_CHECK_TYPE([struct rlimit],[AC_DEFINE([HAVE_STRUCT_RLIMIT],[1],[HAVE_STRUCT_R
 # check for statx
 AC_CHECK_FUNC([statx], [AC_DEFINE([HAVE_STATX_FUN],[1],[HAVE_STATX_FUN])],[],[#include <sys/stat.h>])
 AC_CHECK_TYPE([struct statx],[AC_DEFINE([HAVE_STRUCT_STATX],[1],[HAVE_STRUCT_STATX])],[],[#include <sys/stat.h>])
+AC_MSG_CHECKING(for statx.stx_mnt_id)
+AC_LINK_IFELSE([
+AC_LANG_PROGRAM([[#include <sys/stat.h>]],
+[[
+struct statx statxbuf;
+statx(0, "", 0, STATX_BASIC_STATS | STATX_MNT_ID, &statxbuf);
+return statxbuf.stx_mnt_id;
+]])],
+[
+AC_MSG_RESULT(yes)
+AC_DEFINE([HAVE_STATX_MNT_ID], [1], [Define to 1 if statx.stx_mnt_id is available.])
+],
+[
+AC_MSG_RESULT(no)
+]
+)
+
 
 AC_MSG_CHECKING(for F_GETLK from fcntl.h)
 AC_EGREP_CPP(yes,