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Update the man page
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Authored by ruiu on Dec 11 2019, 7:10 PM.

Details

Summary

Add a description about the compression level of the debug info.

Event Timeline

ruiu created this revision.Dec 11 2019, 7:10 PM
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MaskRay added inline comments.Dec 11 2019, 7:16 PM
lld/docs/ld.lld.1
126

The default is 1.

342

1

ruiu updated this revision to Diff 233489.Dec 11 2019, 7:50 PM
  • address review comment
MaskRay accepted this revision.Dec 11 2019, 8:51 PM

LGTM, but it would probably be wise to get a second pair of eyes on this change.

This revision is now accepted and ready to land.Dec 11 2019, 8:51 PM
grimar added a comment.EditedDec 12 2019, 12:19 AM

A question: do we need to specify the particular compression level in docs? My feeling is that
belongs to internal implementation, it is not really useful for user to know the level probably?

Imagine if we switch to another zlib implementation, like was suggested in the original PR,
what if it doesn't have these levels (I do not know if it has).

What would be probably better is to say something like:
"By default we use a compression, that is fast and effective enough, but if you want to
reduce the size of debug sections even more, you can specify -O2 to enable more aggressive,
but slower compression"

ruiu added a comment.Dec 12 2019, 12:30 AM

A question: do we need to specify the particular compression level in docs? My feeling is that
belongs to internal implementation, it is not really useful for user to know the level probably?

Imagine if we switch to another zlib implementation, like was suggested in the original PR,
what if it doesn't have these levels (I do not know if it has).

What would be probably better is to say something like:
"By default we use a compression, that is fast and effective enough, but if you want to
reduce the size of debug sections even more, you can specify -O2 to enable more aggressive,
but slower compression"

I understand your point, but if I were to read your explanation for the first time, I would wonder what the actual compression levels are. People should be familiar with the notion of the compression level by gzip command option -0, ..., -9, and giving the numbers seems to be a most clear way to tell them what lld is doing. The numbers are not promise or anything, we can change that anytime, since they are only for documentation purpose.

grimar accepted this revision.Dec 12 2019, 12:44 AM

Ok, LGTM

This revision was automatically updated to reflect the committed changes.