- if (@p == 2 &&
- !$haspatches &&
- !$p[0]{IsOrigin} && # breakwater merge never starts with an origin
- !($p[0]{Differs} & ~D_DEB) &&
- !($p[1]{Differs} & ~D_UPS)) {
- return $classify->(qw(BreakwaterUpstreamMerge),
- OrigParents => [ $p[1] ]);
+
+ # The above tells us which way *we* will generate them. But we
+ # might encounter ad-hoc breakwater merges generated manually,
+ # which might be the other way around. In principle, in some odd
+ # situations, a breakwater merge might have two identical parents.
+ # In that case we guess which way round it is (ie, which parent
+ # has the upstream history). The order of the 2-iteration loop
+ # controls which guess we make.
+
+ foreach my $prevbrw (qw(0 1)) {
+ if (@p == 2 &&
+ !$haspatches &&
+ !$p[$prevbrw]{IsOrigin} && # breakwater never starts with an origin
+ !($p[$prevbrw]{Differs} & ~DS_DEB) &&
+ !($p[!$prevbrw]{Differs} & ~D_UPS)) {
+ return $classify->(qw(BreakwaterUpstreamMerge),
+ OrigParents => [ $p[!$prevbrw] ]);
+ }
+ # xxx multi-.orig upstreams