[gcc r11-11489] libgomp: Fix up FLOCK fallback handling [PR113192]

[Jakub Jelinek]

https://gcc.gnu.org/g:58a73ed8e398e05f0c3656cd113f3ca0ee229114

commit r11-11489-g58a73ed8e398e05f0c3656cd113f3ca0ee229114
Author: Jakub Jelinek <jakub@redhat.com>
Date:   Wed Jan 10 13:29:47 2024 +0100

    libgomp: Fix up FLOCK fallback handling [PR113192]
    
    My earlier change broke Solaris testing, because @FLOCK@ isn't substituted
    just into libgomp/Makefile where it worked, but also the
    testsuite/libgomp-site-extra.exp file where Make variables aren't present
    and can't be substituted.
    
    The following patch instead computes the absolute srcdir path and uses it
    for FLOCK.
    
    2024-01-10  Jakub Jelinek  <jakub@redhat.com>
    
            PR libgomp/113192
            * configure.ac (FLOCK): Use $libgomp_abs_srcdir/testsuite/flock
            instead of \$(abs_top_srcdir)/testsuite/flock.
            * configure: Regenerated.
    
    (cherry picked from commit 2fb3ee3ee82874e160309344bc3e52afeed8f26a)

Diff:
---
 libgomp/configure    |  9 ++++++++-
 libgomp/configure.ac | 11 ++++++++++-
 2 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/libgomp/configure b/libgomp/configure
index 6aee94291ea3..07a0efef8eaf 100755
--- a/libgomp/configure
+++ b/libgomp/configure
@@ -16690,6 +16690,13 @@ done
 
 # Fallback if 'perl' is available.
 if test -z "$FLOCK"; then
+  # These need to be absolute paths, yet at the same time need to
+  # canonicalize only relative paths, because then amd will not unmount
+  # drives. Thus the use of PWDCMD: set it to 'pawd' or 'amq -w' if using amd.
+  case $srcdir in
+    [\\/$]* | ?:[\\/]*) libgomp_abs_srcdir=${srcdir} ;;
+    *) libgomp_abs_srcdir=`cd "$srcdir" && ${PWDCMD-pwd} || echo "$srcdir"` ;;
+  esac
   # Extract the first word of "perl", so it can be a program name with args.
 set dummy perl; ac_word=$2
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
@@ -16707,7 +16714,7 @@ do
   test -z "$as_dir" && as_dir=.
     for ac_exec_ext in '' $ac_executable_extensions; do
   if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
-    ac_cv_prog_FLOCK="$srcdir/testsuite/flock"
+    ac_cv_prog_FLOCK="$libgomp_abs_srcdir/testsuite/flock"
     $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
     break 2
   fi
diff --git a/libgomp/configure.ac b/libgomp/configure.ac
index 78a253c0f934..16860255229f 100644
--- a/libgomp/configure.ac
+++ b/libgomp/configure.ac
@@ -335,7 +335,16 @@ AC_MSG_NOTICE([checking for flock implementation])
 AC_CHECK_PROGS(FLOCK, flock)
 # Fallback if 'perl' is available.
 if test -z "$FLOCK"; then
-  AC_CHECK_PROG(FLOCK, perl, $srcdir/testsuite/flock)
+  # These need to be absolute paths, yet at the same time need to
+  # canonicalize only relative paths, because then amd will not unmount
+  # drives. Thus the use of PWDCMD: set it to 'pawd' or 'amq -w' if using amd.
+  case $srcdir in
+changequote(,)dnl
+    [\\/$]* | ?:[\\/]*) libgomp_abs_srcdir=${srcdir} ;;
+changequote([,])dnl
+    *) libgomp_abs_srcdir=`cd "$srcdir" && ${PWDCMD-pwd} || echo "$srcdir"` ;;
+  esac
+  AC_CHECK_PROG(FLOCK, perl, $libgomp_abs_srcdir/testsuite/flock)
 fi
 
 # Get target configury.