Elia Pinto <gitter.spiros@xxxxxxxxx> writes:
> Fix the LGTM warning fired by the rule that finds code that could convert the result of an integer
> multiplication to a larger type. Since the conversion applies after the multiplication,
> arithmetic overflow may still occur.
Overly long?
> chunk_offsets[0] = 8 + (num_chunks + 1) * GRAPH_CHUNKLOOKUP_WIDTH;
> chunk_offsets[1] = chunk_offsets[0] + GRAPH_FANOUT_SIZE;
> - chunk_offsets[2] = chunk_offsets[1] + hashsz * ctx->commits.nr;
> - chunk_offsets[3] = chunk_offsets[2] + (hashsz + 16) * ctx->commits.nr;
> + chunk_offsets[2] = chunk_offsets[1] + (uint64_t)hashsz * ctx->commits.nr;
> + chunk_offsets[3] = chunk_offsets[2] + ((uint64_t)hashsz + 16) * ctx->commits.nr;
chunk_offsets[] is u64[], while hashsz and is uint and
ctx->commits.nr is int. OK.
> @@ -1426,7 +1426,7 @@ static int write_commit_graph_file(struct write_commit_graph_context *ctx)
> }
> if (ctx->num_commit_graphs_after > 1) {
> chunk_offsets[num_chunks + 1] = chunk_offsets[num_chunks] +
> - hashsz * (ctx->num_commit_graphs_after - 1);
> + (uint64_t)hashsz * (ctx->num_commit_graphs_after - 1);
Likewise.
> @@ -1454,7 +1454,7 @@ static int write_commit_graph_file(struct write_commit_graph_context *ctx)
> num_chunks);
> ctx->progress = start_delayed_progress(
> progress_title.buf,
> - num_chunks * ctx->commits.nr);
> + (uint64_t)num_chunks * ctx->commits.nr);
Hmph, do we need this? I understand that the second parameter to
the callee is u64, so the caller needs to come up with u64 without
overflow, but doesn't that automatically get promoted?
> }
> write_graph_chunk_fanout(f, ctx);
> write_graph_chunk_oids(f, hashsz, ctx);
