The analyzer represents all pointer-to-pointer bitcasts the same way, but
this can be problematic if an implicit base cast gets layered on top of a
manual base cast (performed with reinterpret_cast instead of static_cast).
Fix this (and avoid a valid assertion) by looking through cast regions.
Using reinterpret_cast this way is only valid if the base class is at the
same offset as the derived class; this is checked by -Wreinterpret-base-class.
In the interest of performance, the analyzer doesn't repeat this check
anywhere; it will just silently do the wrong thing (use the wrong offsets
for fields of the base class) if the user code is wrong.
PR15394
llvm-svn: 180052
This Decl shouldn't be the canonical Decl; it should be the Decl used by
the CXXBaseSpecifier in the subclass. Unfortunately, that means continuing
to throw getCanonicalDecl() on all comparisons.
This fixes MemRegion::getAsOffset's use of ASTRecordLayout when redeclarations
are involved.
llvm-svn: 175913
- When deciding if we can reuse a lazy binding, make sure to check if there
are additional bindings in the sub-region.
- When reading from a lazy binding, don't accidentally strip off casts or
base object regions. This slows down lazy binding reading a bit but is
necessary for type sanity when treating one class as another.
A bit of minor refactoring allowed these two checks to be unified in a nice
early-return-using helper function.
<rdar://problem/13239840>
llvm-svn: 175703
If a base object is at a 0 offset, RegionStoreManager may find a lazy
binding for the entire object, then try to attach a FieldRegion or
grandparent CXXBaseObjectRegion on top of that (skipping the intermediate
region). We now preserve as many layers of base object regions necessary
to make the types match.
<rdar://problem/13239840>
llvm-svn: 175556
The idea is to eventually place all analyzer options under
"analyzer-config". In addition, this lays the ground for introduction of
a high-level analyzer mode option, which will influence the
default setting for IPAMode.
llvm-svn: 173385
The actual change here is a little more complicated than the summary above.
What we want to do is have our generic inlining tests run under whatever
mode is the default. However, there are some tests that depend on the
presence of C++ inlining, which still has some rough edges. These tests have
been explicitly marked as -analyzer-ipa=inlining in preparation for a new
mode that limits inlining to C functions and blocks. This will be the
default until the false positives for C++ have been brought down to
manageable levels.
llvm-svn: 162317
This can occur with multiple inheritance, which jumps from one parent to
the other, and with virtual inheritance, since virtual base regions always
wrap the actual object and can't be nested within other base regions.
This also exposed some incorrect logic for multiple inheritance: even if B
is known not to derive from C, D might still derive from both of them.
llvm-svn: 161798
...and /do/ strip CXXBaseObjectRegions when casting to a virtual base class.
This allows us to enforce the invariant that a CXXBaseObjectRegion can always
provide an offset for its base region if its base region has a known class
type, by only allowing virtual bases and direct non-virtual bases to form
CXXBaseObjectRegions.
This does mean some slight problems for our modeling of dynamic_cast, which
needs to be resolved by finding a path from the current region to the class
we're trying to cast to.
llvm-svn: 161797
An ASTContext's RecordLayoutInfo can only be used to look up offsets of
direct base classes, and we need the offset to make non-symbolic bindings
in RegionStore. This change makes sure that we have one layer of
CXXBaseObjectRegion for each base we are casting through.
This was causing crashes on an internal buildbot.
llvm-svn: 161621
Jordan Rose