This query is not producing good enough results to justify `@precision
high`. It's fundamentally looking for a pattern that should correlate
with memory management errors, but it doesn't look for the errors
themselves.
This query is supposed to look for constructors that unintentionally qualify as copy constructors due to default arguments. There are quite a few real-world projects that define such constructors intentionally. I've reduced the severity to "warning" and the precision to "low" due to the high false positive rate.
Querying for overlap type wasn't possible when this library was first
written. This change fixes FPs in `RedundantNullCheckSimple.ql` on
Wireshark and other real-world projects.
IR construction was missing support for C++ 11 range-based `for` loops. The extractor generates ASTs for the compiler-generated implementation already, so I had enough information to generate IR. I've expanded on some of the predicates in `RangeBasedForStmt` to access the desugared information.
One complication was that the `DeclStmt`s for the compiler-generated variables seem to have results for `getDeclaration()` but not for `getDeclarationEntry()`. This required handling these slightly differently than we do for other `DeclStmt`s.
The flow for range-based `for` is actually easier than for a regular `for`, because all three components (init, condition, and update) are always present.
It turns out we didn't have to move the `getName` implementation into
the mirror classes in `QualifiedName`. Doing so only made it harder for
the optimiser to specialize calls to `getName` on various kinds of
`Declaration`.
This gains some performance by not computing locations for all
expressions since we are only interested in calls and variable accesses.
The `Top::hasLocationInfo` predicate goes from 2m28s to 1m32s on
Chromium.
This predicate was slow, mostly because it's just very large. A manual
join order cuts the run time on Chromium from
definitions::Top::hasLocationInfo_dispred#ffffff ..................... 3m23s
definitions::MacroAccessWithHasLocationInfo::hasLocationInfo#ffffff .. 1m56s
to
definitions::Top::hasLocationInfo#ffffff .... 2m28s
The main slowdown was the two uses of `SCAN` to reorder columns in the
RA.
