1 files changed, 46 insertions, 0 deletions
diff --git a/m4/perl.m4 b/m4/perl.m4
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index 0000000..0003fcc
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+# serial 10
+
+dnl From Jim Meyering.
+dnl Find a new-enough version of Perl.
+
+# Copyright (C) 1998-2001, 2003-2004, 2007, 2009-2020 Free Software Foundation,
+# Inc.
+#
+# This file is free software; the Free Software Foundation
+# gives unlimited permission to copy and/or distribute it,
+# with or without modifications, as long as this notice is preserved.
+
+AC_DEFUN([gl_PERL],
+[
+  dnl FIXME: don't hard-code 5.005
+  AC_MSG_CHECKING([for perl5.005 or newer])
+  if test "${PERL+set}" = set; then
+    # 'PERL' is set in the user's environment.
+    candidate_perl_names="$PERL"
+    perl_specified=yes
+  else
+    candidate_perl_names='perl perl5'
+    perl_specified=no
+  fi
+
+  found=no
+  AC_SUBST([PERL])
+  PERL="$am_missing_run perl"
+  for perl in $candidate_perl_names; do
+    # Run test in a subshell; some versions of sh will print an error if
+    # an executable is not found, even if stderr is redirected.
+    if ( $perl -e 'require 5.005; use File::Compare; use warnings;' ) > /dev/null 2>&1; then
+      PERL=$perl
+      found=yes
+      break
+    fi
+  done
+
+  AC_MSG_RESULT([$found])
+  test $found = no && AC_MSG_WARN([
+WARNING: You don't seem to have perl5.005 or newer installed, or you lack
+         a usable version of the Perl File::Compare module.  As a result,
+         you may be unable to run a few tests or to regenerate certain
+         files if you modify the sources from which they are derived.
+] )
+])