Derrick Stolee [off-list ref] writes:
It is very subtle, which is why it took me a while to debug this
issue once I managed to trigger it.
quoted
for each commit ctx->commits.list[i]:
continue if generation number has been computed for it already
This is the critical line in the current version. This includes
"continue if the generation number was loaded from the previous
commit-graph file." This means we under-count when building from
an existing commit-graph with overflows.
If we insert an increment here, then we risk double-counting. I
should have described this better.
Ah, that obviously I missed. Thanks.