When a '>>' token is split into two '>' tokens (in C++11 onwards), or (as an
extension) when we do the same for other tokens starting with a '>', we can't
just use a location pointing to the first '>' as the location of the split
token, because that would result in our miscomputing the length and spelling
for the token. As a consequence, for example, a refactoring replacing 'A<X>'
with something else would sometimes replace one character too many, and
similarly diagnostics highlighting a template-id source range would highlight
one character too many.
Fix this by creating an expansion range covering the first character of the
'>>' token, whose spelling is '>'. For this to work, we generalize the
expansion range of a macro FileID to be either a token range (the common case)
or a character range (used in this new case).
llvm-svn: 331155
Avoid crash when the sub-expression of operator delete[] is of array type.
This is not the same as simply using a delete[] syntax.
We're still not properly calling destructors in this case in the analyzer.
Differential Revision: https://reviews.llvm.org/D46146
llvm-svn: 331014
If 'A' is a C++ aggregate with a reference field of type 'C', in code like
A a = { C() };
C() is lifetime-extended by 'a'. The analyzer wasn't expecting this pattern and
crashing. Additionally, destructors aren't added in the CFG for this case,
so for now we shouldn't be inlining the constructor for C().
Differential Revision: https://reviews.llvm.org/D46037
llvm-svn: 330882
Normally the analyzer begins path-sensitive analysis from functions within
the main file, even though the path is allowed to go through any functions
within the translation unit.
When a recent version of WebKit is compiled, the "unified sources" technique
is used, that assumes #including multiple code files into a single main file.
Such file would have no functions defined in it, so the analyzer wouldn't be
able to find any entry points for path-sensitive analysis.
This patch pattern-matches unified file names that are similar to those
used by WebKit and allows the analyzer to find entry points in the included
code files. A more aggressive/generic approach is being planned as well.
Differential Revision: https://reviews.llvm.org/D45839
llvm-svn: 330876
Note diagnostic pieces are an additional way of highlighting code sections to
the user. They aren't part of the normal path diagnostic sequence. They can
also be attached to path-insensitive reports.
Notes are already supported by the text output and scan-build.
Expanding our machine-readable plist output format to be able to represent notes
opens up the possibility for various analyzer GUIs to pick them up.
Patch by Umann Kristóf!
Differential Revision: https://reviews.llvm.org/D45407
llvm-svn: 330766
Printing of ConcreteInts with size >64 bits resulted in assertion failure
in get[Z|S]ExtValue() because these methods are only allowed to be used
with integers of 64 max bit width. This patch fixes the issue.
llvm-svn: 330605
Summary: `TaintBugVisitor` is a universal visitor, and many checkers rely on it, such as `ArrayBoundCheckerV2.cpp`, `DivZeroChecker.cpp` and `VLASizeChecker.cpp`. Moving `TaintBugVisitor` to `BugReporterVisitors.h` enables other checker can also track where `tainted` value came from.
Reviewers: NoQ, george.karpenkov, xazax.hun
Reviewed By: george.karpenkov
Subscribers: szepet, rnkovacs, a.sidorin, cfe-commits, MTC
Differential Revision: https://reviews.llvm.org/D45682
llvm-svn: 330596
If a pointer cast fails (evaluates to an UnknownVal, i.e. not implemented in the
analyzer) and such cast is in fact the last use of the pointer, the pointer
symbol is no longer referenced by the program state and a leak is
(mis-)diagnosed.
"Escape" the pointer upon a failed cast, i.e. inform the checker that we can no
longer reliably track it.
Differential Revision: https://reviews.llvm.org/D45698
llvm-svn: 330380
Summary:
`this` pointer is not an l-value, although we have modeled `CXXThisRegion` for `this` pointer, we can only bind it once, which is when we start to inline method. And this patch fixes https://bugs.llvm.org/show_bug.cgi?id=35506.
In addition, I didn't find any other cases other than loop-widen that could invalidate `this` pointer.
Reviewers: NoQ, george.karpenkov, a.sidorin, seaneveson, szepet
Reviewed By: NoQ
Subscribers: xazax.hun, rnkovacs, cfe-commits, MTC
Differential Revision: https://reviews.llvm.org/D45491
llvm-svn: 330095
Expression rearrangement in SValBuilder (see rL329780) crashes with an assert if the type of the integer is different from the type of the symbol. This fix adds a check that prevents rearrangement in such cases.
Differential Revision: https://reviews.llvm.org/D45557
llvm-svn: 330064
Since the range-based constraint manager (default) is weak in handling comparisons where symbols are on both sides it is wise to rearrange them to have symbols only on the left side. Thus e.g. A + n >= B + m becomes A - B >= m - n which enables the constraint manager to store a range m - n .. MAX_VALUE for the symbolic expression A - B. This can be used later to check whether e.g. A + k == B + l can be true, which is also rearranged to A - B == l - k so the constraint manager can check whether l - k is in the range (thus greater than or equal to m - n).
The restriction in this version is the the rearrangement happens only if both the symbols and the concrete integers are within the range [min/4 .. max/4] where min and max are the minimal and maximal values of their type.
The rearrangement is not enabled by default. It has to be enabled by using -analyzer-config aggressive-relational-comparison-simplification=true.
Co-author of this patch is Artem Dergachev (NoQ).
Differential Revision: https://reviews.llvm.org/D41938
llvm-svn: 329780
Found via codespell -q 3 -I ../clang-whitelist.txt
Where whitelist consists of:
archtype
cas
classs
checkk
compres
definit
frome
iff
inteval
ith
lod
methode
nd
optin
ot
pres
statics
te
thru
Patch by luzpaz! (This is a subset of D44188 that applies cleanly with a few
files that have dubious fixes reverted.)
Differential revision: https://reviews.llvm.org/D44188
llvm-svn: 329399
removeUnneededCalls() is responsible for removing path diagnostic pieces within
functions that don't contain "interesting" events. It makes bug reports
much tidier.
When a stack frame is known to be interesting, the function doesn't descend
into it to prune anything within it, even other callees that are totally boring.
Fix the function to prune boring callees in interesting stack frames.
Differential Revision: https://reviews.llvm.org/D45117
llvm-svn: 329102
Summary:
The original implementation in the `LoopUnrolling.cpp` didn't consider the case where the counter is unsigned. This case is only handled in `simpleCondition()`, but this is not enough, we also need to deal with the unsinged counter with the counter initialization.
Since `IntegerLiteral` is `signed`, there is a `ImplicitCastExpr<IntegralCast>` in `unsigned counter = IntergerLiteral`. This patch add the `ignoringParenImpCasts()` in the `IntegerLiteral` matcher.
Reviewers: szepet, a.sidorin, NoQ, george.karpenkov
Reviewed By: szepet, george.karpenkov
Subscribers: xazax.hun, rnkovacs, cfe-commits, MTC
Differential Revision: https://reviews.llvm.org/D45086
llvm-svn: 328919
Achieves almost a 200% speedup on the example where the performance of
visitors was problematic.
Performance on sqlite3 is unaffected.
rdar://38818362
Differential Revision: https://reviews.llvm.org/D45113
llvm-svn: 328911
Pointer arithmetic on null or undefined pointers results in null or undefined
pointers. This is obvious for undefined pointers; for null pointers it follows
from our incorrect-but-somehow-working approach that declares that 0 (Loc)
doesn't necessarily represent a pointer of numeric address value 0, but instead
it represents any pointer that will cause a valid "null pointer dereference"
issue when dereferenced.
For now we've been seeing through pointer arithmetic at the original dereference
expression, i.e. in bugreporter::getDerefExpr(), but not during further
investigation of the value's origins in bugreporter::trackNullOrUndefValue().
The patch fixes it.
Differential Revision: https://reviews.llvm.org/D45071
llvm-svn: 328896
Not enough work has been done so far to ensure correctness of construction
contexts in the CFG when C++17 copy elision is in effect, so for now we
should drop construction contexts in the CFG and in the analyzer when
they seem different from what we support anyway.
This includes initializations with conditional operators and return values
across multiple stack frames.
Differential Revision: https://reviews.llvm.org/D44854
llvm-svn: 328893
r327219 added wrappers to std::sort which randomly shuffle the container before
sorting. This will help in uncovering non-determinism caused due to undefined
sorting order of objects having the same key.
To make use of that infrastructure we need to invoke llvm::sort instead of
std::sort.
llvm-svn: 328636
Extended the matched assignment operators when checking for bound changes in a body of the loop by using the freshly added isAssignmentOperator matcher.
This covers all the (current) possible assignments, tests added as well.
Differential Revision: https://reviews.llvm.org/D38921
llvm-svn: 328619
Changes the analyzer to believe that methods annotated with _Nonnull
from system frameworks indeed return non null objects.
Local methods with such annotation are still distrusted.
rdar://24291919
Differential Revision: https://reviews.llvm.org/D44341
llvm-svn: 328282
Current location is very confusing, especially because there is already
WorkList.h, and other code in CoreEngine.cpp is not related to work list
implementation.
Differential Revision: https://reviews.llvm.org/D44759
llvm-svn: 328280
When a temporary is constructed with a proper construction context, it should
be safe to inline the destructor. We have added suppressions for some of the
common false positives caused by such inlining, so there should be - and from my
observations there indeed is - more benefit than harm from enabling destructor
inlining.
Differential Revision: https://reviews.llvm.org/D44721
llvm-svn: 328258
CXXCtorInitializer-based constructors are also affected by the C++17 mandatory
copy elision, like variable constructors and return value constructors.
Extend r328248 to support those.
Differential Revision: https://reviews.llvm.org/D44763
llvm-svn: 328255
Function return values can be constructed directly in variables or passed
directly into return statements, without even an elidable copy in between.
This is how the C++17 mandatory copy elision AST behaves. The behavior we'll
have in such cases is the "old" behavior that we've had before we've
implemented destructor inlining and proper lifetime extension support.
Differential Revision: https://reviews.llvm.org/D44755
llvm-svn: 328253
In C++17 copy elision is mandatory for variable and return value constructors
(as long as it doesn't involve type conversion) which results in AST that does
not contain elidable constructors in their usual places. In order to provide
construction contexts in this scenario we need to cover more AST patterns.
This patch makes the CFG prepared for these scenarios by:
- Fork VariableConstructionContext and ReturnedValueConstructionContext into
two different sub-classes (each) one of which indicates the C++17 case and
contains a reference to an extra CXXBindTemporaryExpr.
- Allow CFGCXXRecordTypedCall element to accept VariableConstructionContext and
ReturnedValueConstructionContext as its context.
Differential Revision: https://reviews.llvm.org/D44597
llvm-svn: 328248
Also use the opportunity to clean up the code and remove unnecessary duplication.
rdar://37625895
Differential Revision: https://reviews.llvm.org/D44594
llvm-svn: 327926
My compiler (clang-3.8) complains that the RCC variable is unused.
That's not really true, as it's checked by the if-declaration, but it's
also kinda true, because we don't need to declaration if we only check
it in the if statement.
In reality, all this means that the dyn_cast<> can be replaced by isa<>,
so that's what I do here.
llvm-svn: 327491
Properly perform destruction and lifetime extension of such temporaries.
C++ object-type return values of conservatively evaluated functions are now
represented as compound values of well-defined temporary object regions. The
function creates a region that represents the temporary object and will later
be used for destruction or materialization, invalidates it, and returns the
invalidated compound value of the object.
Differential Revision: https://reviews.llvm.org/D44131
llvm-svn: 327348
This patch uses the newly added CFGCXXRecordTypedCall element at the call site
of the caller to construct the return value within the callee directly into the
caller's stack frame. This way it is also capable of populating the temporary
destructor and lifetime extension maps for the temporary, which allows
temporary destructors and lifetime extension to work correctly.
This patch does not affect temporaries that were returned from conservatively
evaluated functions.
Differential Revision: https://reviews.llvm.org/D44124
llvm-svn: 327345
This patch adds a new CFGStmt sub-class, CFGCXXRecordTypedCall, which replaces
the regular CFGStmt for the respective CallExpr whenever the CFG has additional
information to provide regarding the lifetime of the returned value.
This additional call site information is represented by a ConstructionContext
(which was previously used for CFGConstructor elements) that provides references
to CXXBindTemporaryExpr and MaterializeTemporaryExpr that surround the call.
This corresponds to the common C++ calling convention solution of providing
the target address for constructing the return value as an auxiliary implicit
argument during function call.
One of the use cases for such extra context at the call site would be to perform
any sort of inter-procedural analysis over the CFG that involves functions
returning objects by value. In this case the elidable constructor at the return
site would construct the object explained by the context at the call site, and
its lifetime would also be managed by the caller, not the callee.
The extra context would also be useful for properly handling the return-value
temporary at the call site, even if the callee is not being analyzed
inter-procedurally.
Differential Revision: https://reviews.llvm.org/D44120
llvm-svn: 327343
This patch adds two new CFG elements CFGScopeBegin and CFGScopeEnd that indicate
when a local scope begins and ends respectively. We use first VarDecl declared
in a scope to uniquely identify it and add CFGScopeBegin and CFGScopeEnd elements
into corresponding basic blocks.
Differential Revision: https://reviews.llvm.org/D16403
llvm-svn: 327258
Previously, iteration through nil objects which resulted from
objc-messages being set to nil were modeled incorrectly.
There are a couple of notes about this patch:
In principle, ExprEngineObjC might be left untouched IFF osx.loops
checker is enabled.
I however think that we should not do something
completely incorrect depending on what checkers are left on.
We should evaluate and potentially remove altogether the isConsumedExpr
performance heuristic, as it seems very fragile.
rdar://22205149
Differential Revision: https://reviews.llvm.org/D44178
llvm-svn: 326982
Proper modeling still remains to be done.
Note that BindingDecl#getHoldingVar() is almost always null, and this
should probably be handled by dealing with DecompositionDecl beforehand.
rdar://36852163
Differential Revision: https://reviews.llvm.org/D44183
llvm-svn: 326951
Summary:
There is a problem with analyzer that a wrong value is given when modeling the increment operator of the operand with type bool. After `rL307604` is applied, a unsigned overflow may occur.
Example:
```
void func() {
bool b = true;
// unsigned overflow occur, 2 -> 0 U1b
b++;
}
```
The use of an operand of type bool with the ++ operators is deprecated but valid untill C++17. And if the operand of the increment operator is of type bool, it is set to true.
This patch includes two parts:
- If the operand of the increment operator is of type bool or type _Bool, set to true.
- Modify `BasicValueFactory::getTruthValue()`, use `getIntWidth()` instead `getTypeSize()` and use `unsigned` instead `signed`.
Reviewers: alexshap, NoQ, dcoughlin, george.karpenkov
Reviewed By: NoQ
Subscribers: xazax.hun, szepet, a.sidorin, cfe-commits, MTC
Differential Revision: https://reviews.llvm.org/D43741
llvm-svn: 326776
Don't enable c++-temp-dtor-inlining by default yet, due to this reference
counting pointe problem.
Otherwise the new mode seems stable and allows us to incrementally fix C++
problems in much less hacky ways.
Differential Revision: https://reviews.llvm.org/D43804
llvm-svn: 326461
Richard Smith