[lldb-dev] Is GetLogIf**All**CategoriesSet useful?

[Pavel Labath via lldb-dev]

Hi all,

In case you haven't noticed, I'd like to draw your attention to the 
in-flight patches (https://reviews.llvm.org/D117382, 
https://reviews.llvm.org/D117490) whose goal clean up/improve/streamline 
the logging infrastructure.

I'm don't want go into technical details here (they're on the patch), 
but the general idea is to replace statements like 
GetLogIf(Any/All)CategoriesSet(LIBLLDB_LOG_CAT1 | LIBLLDB_LOG_CAT2)
with
GetLogIf(Any/All)(LLDBLog::Cat1 | LLDBLog::Cat2)
i.e., drop macros and make use of templates to make the function calls 
shorter and safer.

The reason I'm writing this email is to ask about the "All" versions of 
these logging functions. Do you find them useful in practice?

I'm asking that because I've never used this functionality. While I 
can't find anything wrong with the concept in theory, practically I 
think it's just confusing to have some log message appear only for some 
combination of enabled channels. It might have made some sense when we 
had a "verbose" logging channel, but that one is long gone (we still 
have a verbose logging *flag*).

In fact, out of all our GetLogIf calls (1203), less than 1% (11*) uses 
the GetLogIfAll form with more than one category. Of those, three are in 
tests, one is definitely a bug (it combines the category with 
LLDB_LOG_OPTION_VERBOSE), and the others (7) are of questionable 
usefulness (to me anyway).

If we got rid of this, we could simplify the logging calls even further 
and have something like:
Log *log = GetLog(LLDBLog::Process);
everywhere.

cheers,
pl

(*) I used this command to count:
$ git grep -e LogIfAll -A 1 | fgrep -e '|' | wc -l