diff options
| -rw-r--r-- | src/InternPool.zig | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/src/InternPool.zig b/src/InternPool.zig index 64cf95c7b2..681d2b4957 100644 --- a/src/InternPool.zig +++ b/src/InternPool.zig @@ -319,11 +319,18 @@ pub fn rehashTrackedInsts( // We know how big each shard must be, so ensure we have the capacity we need. for (ip.shards) |*shard| { const want_capacity = if (shard.mutate.tracked_inst_map.len == 0) 0 else cap: { - break :cap std.math.ceilPowerOfTwo(u32, shard.mutate.tracked_inst_map.len * 5 / 3) catch unreachable; + // We need to return a capacity of at least 2 to make sure we don't have the `Map(...).empty` value. + // For this reason, note the `+ 1` in the below expression. This matches the behavior of `trackZir`. + break :cap std.math.ceilPowerOfTwo(u32, shard.mutate.tracked_inst_map.len * 5 / 3 + 1) catch unreachable; }; const have_capacity = shard.shared.tracked_inst_map.header().capacity; // no acquire because we hold the mutex if (have_capacity >= want_capacity) { - @memset(shard.shared.tracked_inst_map.entries[0..have_capacity], .{ .value = .none, .hash = undefined }); + if (have_capacity == 1) { + // The map is `.empty` -- we can't memset the entries, or we'll segfault, because + // the buffer is secretly constant. + } else { + @memset(shard.shared.tracked_inst_map.entries[0..have_capacity], .{ .value = .none, .hash = undefined }); + } continue; } var arena = arena_state.promote(gpa); |