Get rid of the dependency on RCS' merge program

diff --git a/git-rerere.perl b/git-rerere.perl
index df119517fe6559a3e5d521f2cf54ea8fadebb36e..2e8dbbd4ea0adcf8aee1e87acfc439e41a7289cf 100755 (executable)
--- a/git-rerere.perl
+++ b/git-rerere.perl
@@ -131,7 +131,11 @@ sub record_preimage {
 sub find_conflict {
        my $in;
        local $/ = "\0";
-       open $in, '-|', qw(git ls-files -z -u) or die "$!: ls-files";
+       my $pid = open($in, '-|');
+       die "$!" unless defined $pid;
+       if (!$pid) {
+               exec(qw(git ls-files -z -u)) or die "$!: ls-files";
+       }
        my %path = ();
        my @path = ();
        while (<$in>) {
@@ -150,7 +154,7 @@ sub find_conflict {
 sub merge {
        my ($name, $path) = @_;
        record_preimage($path, "$rr_dir/$name/thisimage");
-       unless (system('merge', map { "$rr_dir/$name/${_}image" }
+       unless (system('git merge-file', map { "$rr_dir/$name/${_}image" }
                       qw(this pre post))) {
                my $in;
                open $in, "<$rr_dir/$name/thisimage" or