When processing ArrayToPointerDecay, we expect the array to be a location, not a LazyCompoundVal.
Special case the rvalue arrays by using a location to represent them. This case is handled similarly
elsewhere in the code.
Fixes PR16206.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@183359 91177308-0d34-0410-b5e6-96231b3b80d8
In C, 'void' is treated like any other incomplete type, and though it is
never completed, you can cast the address of a void-typed variable to do
something useful. (In C++ it's illegal to declare a variable with void type.)
Previously we asserted on this code; now we just treat it like any other
incomplete type.
And speaking of incomplete types, we don't know their extent. Actually
check that in TypedValueRegion::getExtent, though that's not being used
by any checkers that are on by default.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@182880 91177308-0d34-0410-b5e6-96231b3b80d8
...and don't consider '0' to be a null pointer constant if it's the
initializer for a float!
Apparently null pointer constant evaluation looks through both
MaterializeTemporaryExpr and ImplicitCastExpr, so we have to be more
careful about types in the callers. For RegionStore this just means giving
up a little more; for ExprEngine this means handling the
MaterializeTemporaryExpr case explicitly.
Follow-up to r180894.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@180944 91177308-0d34-0410-b5e6-96231b3b80d8
Previously, this was scattered across Environment (literal expressions),
ExprEngine (default arguments), and RegionStore (global constants). The
former special-cased several kinds of simple constant expressions, while
the latter two deferred to the AST's constant evaluator.
Now, these are all unified as SValBuilder::getConstantVal(). To keep
Environment fast, the special cases for simple constant expressions have
been left in, but the main benefits are that (a) unusual constants like
ObjCStringLiterals now work as default arguments and global constant
initializers, and (b) we're not duplicating code between ExprEngine and
RegionStore.
This actually caught a bug in our test suite, which is awesome: we stop
tracking allocated memory if it's passed as an argument along with some
kind of callback, but not if the callback is 0. We were testing this in
a case where the callback parameter had a default value, but that value
was 0. After this change, the analyzer now (correctly) flags that as a
leak!
<rdar://problem/13773117>
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@180894 91177308-0d34-0410-b5e6-96231b3b80d8
Add a CXXDefaultInitExpr, analogous to CXXDefaultArgExpr, and use it both in
CXXCtorInitializers and in InitListExprs to represent a default initializer.
There's an additional complication here: because the default initializer can
refer to the initialized object via its 'this' pointer, we need to make sure
that 'this' points to the right thing within the evaluation.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@179958 91177308-0d34-0410-b5e6-96231b3b80d8
A C++ overloaded operator may be implemented as an instance method, and
that instance method may be called on an rvalue object, which has no
associated region. The analyzer handles this by creating a temporary region
just for the evaluation of this call; however, it is possible that /by
creating the region/, the analyzer ends up in a previously-explored state.
In this case we don't need to continue along this path.
This doesn't actually show any behavioral change now, but it starts being
used with the next commit and prevents an assertion failure there.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@179766 91177308-0d34-0410-b5e6-96231b3b80d8
While we don't do anything intelligent with pointers-to-members today,
it's perfectly legal to need a temporary of pointer-to-member type to, say,
pass by const reference. Tweak an assertion to allow this.
PR15742 and PR15747
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@179563 91177308-0d34-0410-b5e6-96231b3b80d8
Previously, the analyzer used isIntegerType() everywhere, which uses the C
definition of "integer". The C++ predicate with the same behavior is
isIntegerOrUnscopedEnumerationType().
However, the analyzer is /really/ using this to ask if it's some sort of
"integrally representable" type, i.e. it should include C++11 scoped
enumerations as well. hasIntegerRepresentation() sounds like the right
predicate, but that includes vectors, which the analyzer represents by its
elements.
This commit audits all uses of isIntegerType() and replaces them with the
general isIntegerOrEnumerationType(), except in some specific cases where
it makes sense to exclude scoped enumerations, or any enumerations. These
cases now use isIntegerOrUnscopedEnumerationType() and getAs<BuiltinType>()
plus BuiltinType::isInteger().
isIntegerType() is hereby banned in the analyzer - lib/StaticAnalysis and
include/clang/StaticAnalysis. :-)
Fixes real assertion failures. PR15703 / <rdar://problem/12350701>
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@179081 91177308-0d34-0410-b5e6-96231b3b80d8
The lifetime of a temporary can be extended when it is immediately bound
to a local reference:
const Value &MyVal = Value("temporary");
In this case, the temporary object's lifetime is extended for the entire
scope of the reference; at the end of the scope it is destroyed.
The analyzer was modeling this improperly in two ways:
- Since we don't model temporary constructors just yet, we create a fake
temporary region when it comes time to "materialize" a temporary into
a real object (lvalue). This wasn't taking base casts into account when
the bindings being materialized was Unknown; now it always respects base
casts except when the temporary region is itself a pointer.
- When actually destroying the region, the analyzer did not actually load
from the reference variable -- it was basically destroying the reference
instead of its referent. Now it does do the load.
This will be more useful whenever we finally start modeling temporaries,
or at least those that get bound to local reference variables.
<rdar://problem/13552274>
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@178697 91177308-0d34-0410-b5e6-96231b3b80d8
- Find the correct region to represent the first array element when
constructing a CXXConstructorCall.
- If the array is trivial, model the copy with a primitive load/store.
- Don't warn about the "uninitialized" subscript in the AST -- we don't use
the helper variable that Sema provides.
<rdar://problem/13091608>
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@178602 91177308-0d34-0410-b5e6-96231b3b80d8
Add a new callback that notifies checkers when a const pointer escapes. Currently, this only works
for const pointers passed as a top level parameter into a function. We need to differentiate the const
pointers escape from regular escape since the content pointed by const pointer will not change;
if it’s a file handle, a file cannot be closed; but delete is allowed on const pointers.
This should suppress several false positives reported by the NewDelete checker on llvm codebase.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@178310 91177308-0d34-0410-b5e6-96231b3b80d8
Due to improper modelling of copy constructors (specifically, their
const reference arguments), we were producing spurious leak warnings
for allocated memory stored in structs. In order to silence this, we
decided to consider storing into a struct to be the same as escaping.
However, the previous commit has fixed this issue and we can now properly
distinguish leaked memory that happens to be in a struct from a buffer
that escapes within a struct wrapper.
Originally applied in r161511, reverted in r174468.
<rdar://problem/12945937>
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@177571 91177308-0d34-0410-b5e6-96231b3b80d8
...in favor of this typedef:
typedef llvm::DenseMap<const ExplodedNode *, const ExplodedNode *>
InterExplodedGraphMap;
Use this everywhere the previous class and typedef were used.
Took the opportunity to ArrayRef-ize ExplodedGraph::trim while I'm at it.
No functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@177215 91177308-0d34-0410-b5e6-96231b3b80d8
Normally, we need to look through derived-to-base casts when creating
temporary object regions (added in r175854). However, if the temporary
is a pointer (rather than a struct/class instance), we need to /preserve/
the base casts that have been applied.
This also ensures that we really do create a new temporary region when
we need to: MaterializeTemporaryExpr and lvalue CXXDefaultArgExprs.
Fixes PR15342, although the test case doesn't include the crash because
I couldn't isolate it.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176069 91177308-0d34-0410-b5e6-96231b3b80d8
r175026 added support for default values, but didn't take reference
parameters into account, which expect the default argument to be an
lvalue. Use createTemporaryRegionIfNeeded if we can evaluate the default
expr as an rvalue but the expected result is an lvalue.
Fixes the most recent report of PR12915. The original report predates
default argument support, so that can't be it.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176042 91177308-0d34-0410-b5e6-96231b3b80d8
Use Optional<CFG*> where invalid states were needed previously. In the one case
where that's not possible (beginAutomaticObjDtorsInsert) just use a dummy
CFGAutomaticObjDtor.
Thanks for the help from Jordan Rose & discussion/feedback from Ted Kremenek
and Doug Gregor.
Post commit code review feedback on r175796 by Ted Kremenek.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175938 91177308-0d34-0410-b5e6-96231b3b80d8
This is a follow-up to r175830, which made sure a temporary object region
created for, say, a struct rvalue matched up with the initial bindings
being stored into it. This does the same for the case in which the AST
actually tells us that we need to create a temporary via a
MaterializeObjectExpr. I've unified the two code paths and moved a static
helper function onto ExprEngine.
This also caused a bit of test churn, causing us to go back to describing
temporary regions without a 'const' qualifier. This seems acceptable; it's
our behavior from a few months ago.
<rdar://problem/13265460> (part 2)
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175854 91177308-0d34-0410-b5e6-96231b3b80d8
When creating a temporary region (say, when a struct rvalue is used as
the base of a member expr), make sure we account for any derived-to-base
casts. We don't actually record these in the LazyCompoundVal that
represents the rvalue, but we need to make sure that the temporary region
we're creating (a) matches the bindings, and (b) matches its expression.
Most of the time this will do exactly the same thing as before, but it
fixes spurious "garbage value" warnings introduced in r175234 by the use
of lazy bindings to model trivial copy constructors.
<rdar://problem/13265460>
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175830 91177308-0d34-0410-b5e6-96231b3b80d8
This allows MemRegion and MemRegionManager to avoid asking over and over
again whether an class is a virtual base or a non-virtual base.
Minor optimization/cleanup; no functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175716 91177308-0d34-0410-b5e6-96231b3b80d8
Previously, we were handling only simple integer constants for globals and
the smattering of implicitly-valued expressions handled by Environment for
default arguments. Now, we can use any integer constant expression that
Clang can evaluate, in addition to everything we handled before.
PR15094 / <rdar://problem/12830437>
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175026 91177308-0d34-0410-b5e6-96231b3b80d8
The checkPointerEscape callback previously did not specify how a
pointer escaped. This change includes an enum which describes the
different ways a pointer may escape. This enum is passed to the
checkPointerEscape callback when a pointer escapes. If the escape
is due to a function call, the call is passed. This changes
previous behavior where the call is passed as NULL if the escape
was due to indirectly invalidating the region the pointer referenced.
A patch by Branden Archer!
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@174677 91177308-0d34-0410-b5e6-96231b3b80d8
This is a "quick fix".
The underlining issue is that when a const pointer to a struct is passed
into a function, we do not invalidate the pointer fields. This results
in false positives that are common in C++ (since copy constructors are
prevalent). (Silences two llvm false positives.)
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@174468 91177308-0d34-0410-b5e6-96231b3b80d8
When the analyzer sees an initializer, it checks if the initializer
contains a CXXConstructExpr. If so, it trusts that the CXXConstructExpr
does the necessary work to initialize the object, and performs no further
initialization.
This patch looks through any implicit wrapping expressions like
ExprWithCleanups to find the CXXConstructExpr inside.
Fixes PR15070.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@173557 91177308-0d34-0410-b5e6-96231b3b80d8
This better reflects when callback is called and what the checkers
are relying on. (Both names meant the same pre-IPA.)
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@171432 91177308-0d34-0410-b5e6-96231b3b80d8
Instead of using several callbacks to identify the pointer escape event,
checkers now can register for the checkPointerEscape.
Converted the Malloc checker to use the new callback.
SimpleStreamChecker will be converted next.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@170625 91177308-0d34-0410-b5e6-96231b3b80d8
Fixes a bug, where we were dropping the state modifications from the
checkBranchCondition checker callback.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@170232 91177308-0d34-0410-b5e6-96231b3b80d8
top level.
This heuristic is already turned on for non-ObjC methods
(inlining-mode=noredundancy). If a method has been previously analyzed,
while being inlined inside of another method, do not reanalyze it as top
level.
This commit applies it to ObjCMethods as well. The main caveat here is
that to catch the retain release errors, we are still going to reanalyze
all the ObjC methods but without inlining turned on.
Gives 21% performance increase on one heavy ObjC benchmark, which
suffered large performance regressions due to ObjC inlining.
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This doesn't seem to make much of a difference in practice, but it does
have the potential to avoid a trip through the constraint manager.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@169524 91177308-0d34-0410-b5e6-96231b3b80d8
This feature was probably intended to improve diagnostics, but was currently
only used when dumping the Environment. It shows what location a given value
was loaded from, e.g. when evaluating an LValueToRValue cast.
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uncovered.
This required manually correcting all of the incorrect main-module
headers I could find, and running the new llvm/utils/sort_includes.py
script over the files.
I also manually added quite a few missing headers that were uncovered by
shuffling the order or moving headers up to be main-module-headers.
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This allows us to properly remove dead bindings at the end of the top-level
stack frame, using the ReturnStmt, if there is one, to keep the return value
live. This in turn removes the need for a check::EndPath callback in leak
checkers.
This does cause some changes in the path notes for leak checkers. Previously,
a leak would be reported at the location of the closing brace in a function.
Now, it gets reported at the last statement. This matches the way leaks are
currently reported for inlined functions, but is less than ideal for both.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@168066 91177308-0d34-0410-b5e6-96231b3b80d8
This will simplify checkers that need to register for leaks. Currently,
they have to register for both: check dead and check end of path.
I've modified the SymbolReaper to consider everything on the stack dead
if the input StackLocationContext is 0.
(This is a bit disruptive, so I'd like to flash out all the issues
asap.)
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@167352 91177308-0d34-0410-b5e6-96231b3b80d8