Several headers would fail to compile if other headers were not previously
included. The usual issue is that a class is forward declared, but the
full definition is needed. The requirement for the definition is use of
isa/dyn_cast or calling functions of pointer-packed data types such as
DenseMap or PointerIntPair. Add missing includes to these headers.
SVals.h required an out-of-line method definition in the .cpp file to avoid
circular inclusion of headers with BasicValueFactory.h
llvm-svn: 350913
We need to be able to emit the diagnostic at PreImplicitCall,
and the patch implements this functionality.
However, for now the need for emitting such diagnostics is not all that great:
it is only necessary to not crash when emitting a false positive due to an
unrelated issue of having dead symbol collection not working properly.
Coming up with a non-false-positive test seems impossible with the current
set of checkers, though it is likely to be needed for good things as well
in the future.
Differential Revision: https://reviews.llvm.org/D56042
rdar://problem/46911462
llvm-svn: 350907
The complicated machinery for passing the summary log around is actually
only used for one thing! To figure out whether the "dealloc" message was
sent.
Since I have tried to extend it for other uses and failed (it's actually
very hard to use), I think it's much better to simply use a tag and
remove the summary log altogether.
Differential Revision: https://reviews.llvm.org/D56228
llvm-svn: 350864
Make sure all checks for attributes go through a centralized function,
which checks whether attribute handling is enabled, and performs
validation. The type of the attribute is returned.
Sadly, metaprogramming is required as attributes have no sensible static
getters.
Differential Revision: https://reviews.llvm.org/D56222
llvm-svn: 350862
Summary: The LocationE parameter of evalStore is documented as "The location expression that is stored to". When storing from an increment / decrement operator this was not satisfied. In user code this causes an inconsistency between the SVal and Stmt parameters of checkLocation.
Reviewers: NoQ, dcoughlin, george.karpenkov
Reviewed By: NoQ
Subscribers: xazax.hun, baloghadamsoftware, szepet, a.sidorin, mikhail.ramalho, Szelethus, donat.nagy, dkrupp, cfe-commits
Differential Revision: https://reviews.llvm.org/D55701
llvm-svn: 350528
Previously, argument effects were stored in a method variable, which was
effectively global.
The global state was reset at each (hopefully) entrance point to the
summary construction,
and every function could modify it.
Differential Revision: https://reviews.llvm.org/D56036
llvm-svn: 350057
This patch is a different approach to landing the reverted r349701.
It is expected to have the same object (memory region) treated as if it has
different types in different program points. The correct behavior for
RegionStore when an object is stored as an object of type T1 but loaded as
an object of type T2 is to store the object as if it has type T1 but cast it
to T2 during load.
Note that the cast here is some sort of a "reinterpret_cast" (even in C). For
instance, if you store an integer and load a float, you won't get your integer
represented as a float; instead, you will get garbage.
Admit that we cannot perform the cast and return an unknown value.
Differential Revision: https://reviews.llvm.org/D55875
rdar://problem/45062567
llvm-svn: 349984
The fix done in D55465 did not previously apply when the function was inlined.
rdar://46889541
Differential Revision: https://reviews.llvm.org/D55976
llvm-svn: 349876
Previously, we were not printing a note at all if at least one of the parameters was not annotated.
rdar://46888422
Differential Revision: https://reviews.llvm.org/D55972
llvm-svn: 349875
If it ends with "Retain" like CFRetain and returns a CFTypeRef like CFRetain,
then it is not necessarily a CFRetain. But it is indeed true that these two
return something retained.
Differential Revision: https://reviews.llvm.org/D55907
rdar://problem/39390714
llvm-svn: 349862
This adds anchors to all of the documented checks so that you can directly link to a check by a stable name. This is useful because the SARIF file format has a field for specifying a URI to documentation for a rule and some viewers, like CodeSonar, make use of this information. These links are then exposed through the SARIF exporter.
llvm-svn: 349812
This reverts commit r349701.
The patch was incorrect. The whole point of CastRetrievedVal()
is to handle the case in which the type from which the cast is made
(i.e., the "type" of value `V`) has nothing to do with the type of
the region it was loaded from (i.e., `R->getValueType()`).
Differential Revision: https://reviews.llvm.org/D55875
rdar://problem/45062567
llvm-svn: 349798
Replace multiple comparisons of getOS() value with FreeBSD, NetBSD,
OpenBSD and DragonFly with matching isOS*BSD() methods. This should
improve the consistency of coding style without changing the behavior.
Direct getOS() comparisons were left whenever used in switch or switch-
like context.
Differential Revision: https://reviews.llvm.org/D55916
llvm-svn: 349752
It is expected to have the same object (memory region) treated as if it has
different types in different program points. The correct behavior for
RegionStore when an object is stored as an object of type T1 but loaded as
an object of type T2 is to store the object as if it has type T1 but cast it
to T2 during load.
Note that the cast here is some sort of a "reinterpret_cast" (even in C). For
instance, if you store a float and load an integer, you won't have your float
rounded to an integer; instead, you will have garbage.
Admit that we cannot perform the cast as long as types we're dealing with are
non-trivial (neither integers, nor pointers).
Of course, if the cast is not necessary (eg, T1 == T2), we can still load the
value just fine.
Differential Revision: https://reviews.llvm.org/D55875
rdar://problem/45062567
llvm-svn: 349701
Static Analyzer processes the program function-by-function, sometimes diving
into other functions ("inlining" them). When an object is returned from an
inlined function, Return Value Optimization is modeled, and the returned object
is constructed at its return location directly.
When an object is returned from the function from which the analysis has started
(the top stack frame of the analysis), the return location is unknown. Model it
with a SymbolicRegion based on a conjured symbol that is specifically tagged for
that purpose, because this is generally the correct way to symbolicate
unknown locations in Static Analyzer.
Fixes leak false positives when an object is returned from top frame in C++17:
objects that are put into a SymbolicRegion-based memory region automatically
"escape" and no longer get reported as leaks. This only applies to C++17 return
values with destructors, because it produces a redundant CXXBindTemporaryExpr
in the call site, which confuses our liveness analysis. The actual fix
for liveness analysis is still pending, but it is no longer causing problems.
Additionally, re-enable temporary destructor tests in C++17.
Differential Revision: https://reviews.llvm.org/D55804
rdar://problem/46217550
llvm-svn: 349696
It turns out that it's not all that uncommon to have a C++ override of, say,
memcpy that receives a structure (or two) by reference (or by value, if it's
being copied from) and copies memory from it (or into it, if it's passed
by reference). In this case the argument will be of structure type (recall that
expressions of reference type do not exist: instead, C++ classifies expressions
into prvalues and lvalues and xvalues).
In this scenario we crash because we are trying to assume that, say,
a memory region is equal to an empty CompoundValue (the non-lazy one; this is
what makeZeroVal() return for compound types and it represents prvalue of
an object that is initialized with an empty initializer list).
Add defensive checks.
Differential Revision: https://reviews.llvm.org/D55873
rdar://problem/45366551
llvm-svn: 349682
Accidentally commited earlier with the same commit title, but really it
should've been
"Revert rC349283 '[analyzer][MallocChecker] Improve warning messages on double-delete errors'"
llvm-svn: 349344
Re-using a moved-from local variable is most likely a bug because there's
rarely a good motivation for not introducing a separate variable instead.
We plan to keep emitting such warnings by default.
Introduce a flag that allows disabling warnings on local variables that are
not of a known move-unsafe type. If it doesn't work out as we expected,
we'll just flip the flag.
We still warn on move-unsafe objects and unsafe operations on known move-safe
objects.
Differential Revision: https://reviews.llvm.org/D55730
llvm-svn: 349327
This re-applies commit r349226 that was reverted in r349233 due to failures
on clang-x64-windows-msvc.
Specify enum type as unsigned for use in bit field. Otherwise overflows
may cause UB.
Differential Revision: https://reviews.llvm.org/D55388
llvm-svn: 349326
StaticAnalyzer uses the CFG-based RelaxedLiveVariables analysis in order to,
in particular, figure out values of which expressions are still needed.
When the expression becomes "dead", it is garbage-collected during
the dead binding scan.
Expressions that constitute branches/bodies of control flow statements,
eg. `E1' in `if (C1) E1;' but not `E2' in `if (C2) { E2; }', were kept alive
for too long. This caused false positives in MoveChecker because it relies
on cleaning up loop-local variables when they go out of scope, but some of those
live-for-too-long expressions were keeping a reference to those variables.
Fix liveness analysis to correctly mark these expressions as dead.
Add a debug checker, debug.DumpLiveStmts, in order to test expressions liveness.
Differential Revision: https://reviews.llvm.org/D55566
llvm-svn: 349320
This patch merely reorganizes some things, and features no functional change.
In detail:
* Provided documentation, or moved existing documentation in more obvious
places.
* Added dividers. (the //===----------===// thing).
* Moved getAllocationFamily, printAllocDeallocName, printExpectedAllocName and
printExpectedDeallocName in the global namespace on top of the file where
AllocationFamily is declared, as they are very strongly related.
* Moved isReleased and MallocUpdateRefState near RefState's definition for the
same reason.
* Realloc modeling was very poor in terms of variable and structure naming, as
well as documentation, so I renamed some of them and added much needed docs.
* Moved function IdentifierInfos to a separate struct, and moved isMemFunction,
isCMemFunction adn isStandardNewDelete inside it. This makes the patch affect
quite a lot of lines, should I extract it to a separate one?
* Moved MallocBugVisitor out of MallocChecker.
* Preferred switches to long else-if branches in some places.
* Neatly organized some RUN: lines.
Differential Revision: https://reviews.llvm.org/D54823
llvm-svn: 349281
Now that CheckerRegistry lies in Frontend, we can finally eliminate
ClangCheckerRegistry. Fortunately, this also provides us with a
DiagnosticsEngine, so I went ahead and removed some parameters from it's
methods.
Differential Revision: https://reviews.llvm.org/D54437
llvm-svn: 349280
ClangCheckerRegistry is a very non-obvious, poorly documented, weird concept.
It derives from CheckerRegistry, and is placed in lib/StaticAnalyzer/Frontend,
whereas it's base is located in lib/StaticAnalyzer/Core. It was, from what I can
imagine, used to circumvent the problem that the registry functions of the
checkers are located in the clangStaticAnalyzerCheckers library, but that
library depends on clangStaticAnalyzerCore. However, clangStaticAnalyzerFrontend
depends on both of those libraries.
One can make the observation however, that CheckerRegistry has no place in Core,
it isn't used there at all! The only place where it is used is Frontend, which
is where it ultimately belongs.
This move implies that since
include/clang/StaticAnalyzer/Checkers/ClangCheckers.h only contained a single function:
class CheckerRegistry;
void registerBuiltinCheckers(CheckerRegistry ®istry);
it had to re purposed, as CheckerRegistry is no longer available to
clangStaticAnalyzerCheckers. It was renamed to BuiltinCheckerRegistration.h,
which actually describes it a lot better -- it does not contain the registration
functions for checkers, but only those generated by the tblgen files.
Differential Revision: https://reviews.llvm.org/D54436
llvm-svn: 349275
Renaming collectCheckers to getEnabledCheckers
Changing the functionality to acquire all enabled checkers, rather then collect
checkers for a specific CheckerOptInfo (for example, collecting all checkers for
{ "core", true }, which meant enabling all checkers from the core package, which
was an unnecessary complication).
Removing CheckerOptInfo, instead of storing whether the option was claimed via a
field, we handle errors immediately, as getEnabledCheckers can now access a
DiagnosticsEngine. Realize that the remaining information it stored is directly
accessible through AnalyzerOptions.CheckerControlList.
Fix a test with -analyzer-disable-checker -verify accidentally left in.
llvm-svn: 349274
Right now they report to have one parameter with null decl,
because initializing an ArrayRef of pointers with a nullptr
yields an ArrayRef to an array of one null pointer.
Fixes a crash in the OSObject section of RetainCountChecker.
Differential Revision: https://reviews.llvm.org/D55671
llvm-svn: 349229
The checker wasn't prepared to see the dealloc message sent to the class itself
rather than to an instance, as if it was +dealloc.
Additionally, it wasn't prepared for pure-unknown or undefined self values.
The new guard covers that as well, but it is annoying to test because
both kinds of values shouldn't really appear and we generally want to
get rid of all of them (by modeling unknown values with symbols and
by warning on use of undefined values before they are used).
The CHECK: directive for FileCheck at the end of the test looks useless,
so i removed it.
Differential Revision: https://reviews.llvm.org/D55680
llvm-svn: 349228
Use trackExpressionValue() (previously known as trackNullOrUndefValue())
to track index value in the report, so that the user knew
what Static Analyzer thinks the index is.
Additionally, implement printState() to help debugging the checker later.
Differential Revision: https://reviews.llvm.org/D55458
llvm-svn: 349227
Calling operator*() or operator->() on a null STL smart pointer is
undefined behavior.
Smart pointers are specified to become null after being moved from.
So we can't warn on arbitrary method calls, but these two operators
definitely make no sense.
The new bug is fatal because it's an immediate UB,
unlike other use-after-move bugs.
The work on a more generic null smart pointer dereference checker
is still pending.
Differential Revision: https://reviews.llvm.org/D55388
llvm-svn: 349226
Some C++ standard library classes provide additional guarantees about their
state after move. Suppress warnings on such classes until a more precise
behavior is implemented. Warnings for locals are not suppressed anyway
because it's still most likely a bug.
Differential Revision: https://reviews.llvm.org/D55307
llvm-svn: 349191
If a moved-from object is passed into a conservatively evaluated function
by pointer or by reference, we assume that the function may reset its state.
Make sure it doesn't apply to const pointers and const references. Add a test
that demonstrates that it does apply to rvalue references.
Additionally, make sure that the object is invalidated when its contents change
for reasons other than invalidation caused by evaluating a call conservatively.
In particular, when the object's fields are manipulated directly, we should
assume that some sort of reset may be happening.
Differential Revision: https://reviews.llvm.org/D55289
llvm-svn: 349190
Functional changes include:
* The run.files property is now an array instead of a mapping.
* fileLocation objects now have a fileIndex property specifying the array index into run.files.
* The resource.rules property is now an array instead of a mapping.
* The result object was given a ruleIndex property that is an index into the resource.rules array.
* rule objects now have their "id" field filled out in addition to the name field.
* Updated the schema and spec version numbers to 11-28.
llvm-svn: 349188
- explicit_bzero has limited scope/usage only for security/crypto purposes but is non-optimisable version of memset/0 and bzero.
- explicit_memset has similar signature and semantics as memset but is also a non-optimisable version.
Reviewers: NoQ
Reviewed By: NoQ
Differential Revision: https://reviews.llvm.org/D54592
llvm-svn: 348884
Memoization dose not seem to be necessary, as other statement visitors
run just fine without it,
and in fact seems to be causing memory corruptions.
Just removing it instead of investigating the root cause.
rdar://45945002
Differential Revision: https://reviews.llvm.org/D54921
llvm-svn: 348822
This is currently a diagnostics, but might be upgraded to an error in the future,
especially if we introduce os_return_on_success attributes.
rdar://46359592
Differential Revision: https://reviews.llvm.org/D55530
llvm-svn: 348820
Escaping to void * / uint64_t / others non-OSObject * should stop tracking,
as such functions can have heterogeneous semantics depending on context,
and can not always be annotated.
rdar://46439133
Differential Revision: https://reviews.llvm.org/D55465
llvm-svn: 348675
Allow enabling and disabling tracking of ObjC/CF objects
separately from tracking of OS objects.
Differential Revision: https://reviews.llvm.org/D55400
llvm-svn: 348638
The option has no tests, is not used anywhere, and is actually
incorrect: it prints the line number without the reference to a file,
which can be outright incorrect.
Differential Revision: https://reviews.llvm.org/D55385
llvm-svn: 348637
Summary:
With a new switch we may be able to print to stderr if a new TU is being loaded
during CTU. This is very important for higher level scripts (like CodeChecker)
to be able to parse this output so they can create e.g. a zip file in case of
a Clang crash which contains all the related TU files.
Reviewers: xazax.hun, Szelethus, a_sidorin, george.karpenkov
Subscribers: whisperity, baloghadamsoftware, szepet, rnkovacs, a.sidorin, mikhail.ramalho, donat.nagy, dkrupp,
Differential Revision: https://reviews.llvm.org/D55135
llvm-svn: 348594
Previously, the iterator range checker only warned upon dereferencing of
iterators outside their valid range as well as increments and decrements of
out-of-range iterators where the result remains out-of-range. However, the C++
standard is more strict than this: decrementing begin() or incrementing end()
results in undefined behaviour even if the iterator is not dereferenced
afterwards. Coming back to the range once out-of-range is also undefined.
This patch corrects the behaviour of the iterator range checker: warnings are
given for any operation whose result is ahead of begin() or past the end()
(which is the past-end iterator itself, thus now we are speaking of past
past-the-end).
Differential Revision: https://reviews.llvm.org/D53812
llvm-svn: 348245
If an iterator is represented by a derived C++ class but its comparison operator
is for its base the iterator checkers cannot recognize the iterators compared.
This results in false positives in very straightforward cases (range error when
dereferencing an iterator after disclosing that it is equal to the past-the-end
iterator).
To overcome this problem we always use the region of the topmost base class for
iterators stored in a region. A new method called getMostDerivedObjectRegion()
was added to the MemRegion class to get this region.
Differential Revision: https://reviews.llvm.org/D54466
llvm-svn: 348244
Includes "resize" and "shrink" because they can reset the object to a known
state in certain circumstances.
Differential Revision: https://reviews.llvm.org/D54563
llvm-svn: 348235
The warning piece traditionally describes the bug itself, i.e.
"The bug is a _____", eg. "Attempt to delete released memory",
"Resource leak", "Method call on a moved-from object".
Event pieces produced by the visitor are usually in a present tense, i.e.
"At this moment _____": "Memory is released", "File is closed",
"Object is moved".
Additionally, type information is added into the event pieces for STL objects
(in order to highlight that it is in fact an STL object), and the respective
event piece now mentions that the object is left in an unspecified state
after it was moved, which is a vital piece of information to understand the bug.
Differential Revision: https://reviews.llvm.org/D54560
llvm-svn: 348229
In general case there use-after-move is not a bug. It depends on how the
move-constructor or move-assignment is implemented.
In STL, the convention that applies to most classes is that the move-constructor
(-assignment) leaves an object in a "valid but unspecified" state. Using such
object without resetting it to a known state first is likely a bug. Objects
Local value-type variables are special because due to their automatic lifetime
there is no intention to reuse space. If you want a fresh object, you might
as well make a new variable, no need to move from a variable and than re-use it.
Therefore, it is not always a bug, but it is obviously easy to suppress when it
isn't, and in most cases it indeed is - as there's no valid intention behind
the intentional use of a local after move.
This applies not only to local variables but also to parameter variables,
not only of value type but also of rvalue reference type (but not to lvalue
references).
Differential Revision: https://reviews.llvm.org/D54557
llvm-svn: 348210
The checker had extra code to clean up memory regions that were sticking around
in the checker without ever being cleaned up due to the bug that was fixed in
r347953. Because of that, if a region was moved from, then became dead,
and then reincarnated, there were false positives.
Why regions are even allowed to reincarnate is a separate story. Luckily, this
only happens for local regions that don't produce symbols when loaded from.
No functional change intended. The newly added test demonstrates that even
though no cleanup is necessary upon destructor calls, the early return
cannot be removed. It was not failing before the patch.
Differential Revision: https://reviews.llvm.org/D54372
llvm-svn: 348208
This follows the Static Analyzer's tradition to name checkers after
things in which they find bugs, not after bugs they find.
Differential Revision: https://reviews.llvm.org/D54556
llvm-svn: 348201
This continues the work that was started in r342313, which now gets applied to
object-under-construction tracking in C++. Makes it possible to debug
temporaries by dumping exploded graphs again.
Differential Revision: https://reviews.llvm.org/D54459
llvm-svn: 348200
Buildbot failures were caused by an unrelated UB that was introduced in r347943
and fixed in r347970.
Also the revision was incorrectly specified as r344580 during revert.
Differential Revision: https://reviews.llvm.org/D54017
llvm-svn: 348188
It seems the two failing tests can be simply fixed after r348037
Fix 3 cases in Analysis/builtin-functions.cpp
Delete the bad CodeGen/builtin-constant-p.c for now
llvm-svn: 348053
Kept the "indirect_builtin_constant_p" test case in test/SemaCXX/constant-expression-cxx1y.cpp
while we are investigating why the following snippet fails:
extern char extern_var;
struct { int a; } a = {__builtin_constant_p(extern_var)};
llvm-svn: 348039
In earlier patches regarding AnalyzerOptions, a lot of effort went into
gathering all config options, and changing the interface so that potential
misuse can be eliminited.
Up until this point, AnalyzerOptions only evaluated an option when it was
querried. For example, if we had a "-no-false-positives" flag, AnalyzerOptions
would store an Optional field for it that would be None up until somewhere in
the code until the flag's getter function is called.
However, now that we're confident that we've gathered all configs, we can
evaluate off of them before analysis, so we can emit a error on invalid input
even if that prticular flag will not matter in that particular run of the
analyzer. Another very big benefit of this is that debug.ConfigDumper will now
show the value of all configs every single time.
Also, almost all options related class have a similar interface, so uniformity
is also a benefit.
The implementation for errors on invalid input will be commited shorty.
Differential Revision: https://reviews.llvm.org/D53692
llvm-svn: 348031
From what I can see, this should be the last patch needed to replicate macro
argument expansions.
Differential Revision: https://reviews.llvm.org/D52988
llvm-svn: 348025
During the review of D41938 a condition check with an early exit accidentally
slipped into a branch, leaving the other branch unprotected. This may result in
an assertion later on. This hotfix moves this contition check outside of the
branch.
Differential Revision: https://reviews.llvm.org/D55051
llvm-svn: 347981
Don't generate a checker-tagged node unconditionally on the first
checkDeadSymbols callback when no pointers are tracked.
This is a tiny performance optimization; it may change the behavior slightly
by making Static Analyzer bail out on max-nodes one node later (which is good)
but any test would either break for no good reason or become useless
every time someone sneezes.
Differential Revision: https://reviews.llvm.org/D54013
llvm-svn: 347955
The checker suppresses warnings on paths on which a nonnull value is assumed
to be nullable. This probably deserves a warning, but it's a separate story.
Now, because dead symbol collection fires in pretty random moments,
there sometimes was a situation when dead symbol collection fired after
computing a parameter but before actually evaluating call enter into the
function, which triggered the suppression when the argument was null
in the first place earlier than the obvious warning for null-to-nonnull
was emitted, causing false negatives.
Only trigger the suppression for symbols, not for concrete values.
It is impossible to constrain a concrete value post-factum because
it is impossible to constrain a concrete value at all.
This covers all the necessary cases because by the time we reach the call,
symbolic values should be either not constrained to null, or already collapsed
into concrete null values. Which in turn happens because they are passed through
the Store, and the respective collapse is implemented as part of getSVal(),
which is also weird.
Differential Revision: https://reviews.llvm.org/D54017
llvm-svn: 347954
It's an old bug that consists in stale references to symbols remaining in the
GDM if they disappear from other program state sections as a result of any
operation that isn't the actual dead symbol collection. The most common example
here is:
FILE *fp = fopen("myfile.txt", "w");
fp = 0; // leak of file descriptor
In this example the leak were not detected previously because the symbol
disappears from the public part of the program state due to evaluating
the assignment. For that reason the checker never receives a notification
that the symbol is dead, and never reports a leak.
This patch not only causes leak false negatives, but also a number of other
problems, including false positives on some checkers.
What's worse, even though the program state contains a finite number of symbols,
the set of symbols that dies is potentially infinite. This means that is
impossible to compute the set of all dead symbols to pass off to the checkers
for cleaning up their part of the GDM.
No longer compute the dead set at all. Disallow iterating over dead symbols.
Disallow querying if any symbols are dead. Remove the API for marking symbols
as dead, as it is no longer necessary. Update checkers accordingly.
Differential Revision: https://reviews.llvm.org/D18860
llvm-svn: 347953
The "free" call frees the object immediately, ignoring the reference count.
Sadly, it is actually used in a few places, so we need to model it.
Differential Revision: https://reviews.llvm.org/D55092
llvm-svn: 347950
Move visitors to the implementation file, move a complicated logic into
a function.
Differential Revision: https://reviews.llvm.org/D55036
llvm-svn: 347946
Attempt to get a fully qualified name from AST if an SVal corresponding
to the object is not available.
Differential Revision: https://reviews.llvm.org/D55034
llvm-svn: 347944
If the object is a temporary, and there is no variable it binds to,
let's at least print out the object name in order to help differentiate
it from other temporaries.
rdar://45175098
Differential Revision: https://reviews.llvm.org/D55033
llvm-svn: 347943
Richard Trieu