When a temporary object is materialized and through that obtain lifetime that
is longer than the duration of the full-expression, it does not require a
temporary object destructor; it will be destroyed in a different manner.
Therefore it's not necessary to include CXXBindTemporaryExpr into the
construction context for such temporary in the CFG only to make clients
throw it away.
Differential Revision: https://reviews.llvm.org/D47667
llvm-svn: 335798
In code like
const int &x = A().x;
automatic destructor for the object A() lifetime-extended by reference 'x' was
not present in the clang CFG due to ad-hoc pattern-matching in
getReferenceInitTemporaryType().
Re-use skipRValueSubobjectAdjustments() again to find the lifetime-extended
object in the AST and emit the correct destructor.
Lifetime extension through aggregates with references still needs to be covered.
Differential Revision: https://reviews.llvm.org/D44238
llvm-svn: 333941
Loop condition variables, eg.
while (shared_ptr<int> P = getIntPtr()) { ... })
weren't handled in r324794 because they don't go through the common
CFGBuilder::VisitDeclStmt method. Which means that they regressed
after r324800.
Fix the regression by duplicating the necessary construction context scan in
the loop visiting code.
Differential Revision: https://reviews.llvm.org/D45706
llvm-svn: 330382
In order to bind a temporary to a const lvalue reference, a no-op cast is added
to make the temporary itself const, and only then the reference is taken
(materialized). Skip the no-op cast when looking for the construction context.
Differential Revision: https://reviews.llvm.org/D43481
llvm-svn: 326016
Constructors of C++ temporary objects that have destructors now can be queried
to discover that they're indeed constructing temporary objects.
The respective CXXBindTemporaryExpr, which is also repsonsible for destroying
the temporary at the end of full-expression, is now available at the
construction site in the CFG. This is all the context we need to provide for
temporary objects that are not lifetime extended. For lifetime-extended
temporaries, more context is necessary.
Differential Revision: https://reviews.llvm.org/D43056
llvm-svn: 325210
Constructors of simple variables now can be queried to discover that they're
constructing into simple variables.
Differential Revision: https://reviews.llvm.org/D42699
llvm-svn: 324794
Summary:
I've had a test failure here while experimenting and I've found that it's
impossible to find what is wrong with the previous structure of the file. So I
have grouped the expected output with the function that produces it, to make
searching for discrepancies more obvious.
Reviewers: jordan_rose
CC: cfe-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D1595
llvm-svn: 190037
While destructors will continue to not be inlined (unless the analyzer
config option 'c++-inlining' is set to 'destructors'), leaving them out
of the CFG is an incomplete model of the behavior of an object, and
can cause false positive warnings (like PR13751, now working).
Destructors for temporaries are still not on by default, since
(a) we haven't actually checked this code to be sure it's fully correct
(in particular, we probably need to be very careful with regard to
lifetime-extension when a temporary is bound to a reference,
C++11 [class.temporary]p5), and
(b) ExprEngine doesn't actually do anything when it sees a temporary
destructor in the CFG -- not even invalidate the object region.
To enable temporary destructors, set the 'cfg-temporary-dtors' analyzer
config option to '1'. The old -cfg-add-implicit-dtors cc1 option, which
controlled all implicit destructors, has been removed.
llvm-svn: 163264
instead push the terminator for the branch down into the basic blocks of the subexpressions of '&&' and '||'
respectively. This eliminates some artifical control-flow from the CFG and results in a more
compact CFG.
Note that this patch only alters the branches 'while', 'if' and 'for'. This was complex enough for
one patch. The remaining branches (e.g., do...while) can be handled in a separate patch, but they
weren't immediately tackled because they were less important.
It is possible that this patch introduces some subtle bugs, particularly w.r.t. to destructor placement.
I've tried to audit these changes, but it is also known that the destructor logic needs some refinement
in the area of '||' and '&&' regardless (i.e., their are known bugs).
llvm-svn: 160218
AnalysisConsumer.
As a result:
- We now analyze the C++ methods which are defined within the
class body. These were completely skipped before.
- Ensure that AST checkers are called on functions in the
order they are defined in the Translation unit.
llvm-svn: 152650
as aborted, but didn't treat such cases as sinks in the ExplodedGraph.
Along the way, add basic support for CXXCatchStmt, expanding the set of code we actually analyze (hopefully correctly).
Fixes: <rdar://problem/10892489>
llvm-svn: 152468
The motivation of this large change is to drastically simplify the logic in ExprEngine going forward.
Some fallout is that the output of some BugReporterVisitors is not as accurate as before; those will
need to be fixed over time. There is also some possible performance regression as RemoveDeadBindings
will be called frequently; this can also be improved over time.
llvm-svn: 136419
1) Change the CFG to include the DeclStmt for conditional variables, instead of using the condition itself as a faux DeclStmt.
2) Update ExprEngine (the static analyzer) to understand (1), so not to regress.
3) Update UninitializedValues.cpp to initialize all tracked variables to Uninitialized at the start of the function/method.
4) Only use the SelfReferenceChecker (SemaDecl.cpp) on global variables, leaving the dataflow analysis to handle other cases.
The combination of (1) and (3) allows the dataflow-based -Wuninitialized to find self-init problems when the initializer
contained control-flow.
llvm-svn: 128858
The relative checker package is 'debug':
'-dump-live-variables' is replaced by '-analyzer-checker=debug.DumpLiveVars'
'-cfg-view' is replaced by '-analyzer-checker=debug.ViewCFG'
'-cfg-dump' is replaced by '-analyzer-checker=debug.DumpCFG'
llvm-svn: 125780
- Adding LocalScope for CompoundStmt,
- Adding CFGAutomaticObjDtors for end of scope, return, goto, break, continue,
- Regression tests for above cases.
llvm-svn: 115252
Artem Dergachev