Hi, On Tue, Apr 22, 2025 at 12:31:18PM +0000, Pranav P wrote: > Hi, > > When running `make test` on an s390x machine in Debian it is failing on 'do partial clone 2, backfill min batch size' > Reference: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1102106 > > After processing the command line arguments structure member min_batch_size should have had the value 20 > > Instead of having the value 20 (--min-batch-size=20) it was having a very large value > > min_batch_size in `struct backfill_context` is of type `size_t` and since in the function cmd_backfill, in the > options struct it is passed on to OPT_INTEGER, which eventually causes > > ``` > *(int *)opt->value = strtol(arg, (char **)&s, 10); > ``` > in parse-options.c line 188. This is writing the data in the first 4 bytes of min_batch_size and on big endian > systems this will lead min_batch_size to be a big number. This issue is immediately visible in little endian systems. > > Changing OPT_INTEGER to OPT_MAGNITUDE seems to be working on x86 and s390x Yup, indeed. > ``` > diff --git a/builtin/backfill.c b/builtin/backfill.c > index 18f9701487..33e1ea2f84 100644 > --- a/builtin/backfill.c > +++ b/builtin/backfill.c > @@ -123,7 +123,7 @@ int cmd_backfill(int argc, const char **argv, const char *prefix, struct reposit > .sparse = 0, > }; > struct option options[] = { > - OPT_MAGNITUDE(0, "min-batch-size", &ctx.min_batch_size, > + OPT_INTEGER(0, "min-batch-size", &ctx.min_batch_size, > N_("Minimum number of objects to request at a time")), > OPT_BOOL(0, "sparse", &ctx.sparse, > N_("Restrict the missing objects to the current sparse-checkout")), > ``` > > But on systems where size_t which not be unsigned long, this might lead to an issue. > So, one other suggestion I have is to change the data type of min_batch_size from size_t to int. But I am not able to > determine whether a practical upper bound for min_batch_size would exceed what an int variable can store. > With that clarification, I can a raise patch for the issue. True, as well. Overall the current state is a bit unfortunate because it's so easy to get this wrong, and the compiler won't even spit out a warning. > I am fairly new to opensource and was following the `git bugreport`. So I am extremely sorry for any lack of clarity in the report. No need to be sorry, this bug report contains all the details we'd need and is of quite high quality :) The only thing is that we've already got this bug reported via [1]. The underlying issue is addressed via [2], which has already been merged to `next`. It also fixes the underlying issue you observed with different integer widths as well as with signedness. Thanks! Patrick [1]: https://lore.kernel.org/git/89257ab82cd60d135cce02d51eacee7ec35c1c37.camel@xxxxxxxxxxxxxxxxxxx/ [2]: https://lore.kernel.org/git/20250401-b4-pks-parse-options-integers-v1-0-a628ad40c3b4@xxxxxx/
