Commit Graph

2090 Commits

Author SHA1 Message Date
David Blaikie 1def2579e1 PR51018: Remove explicit conversions from SmallString to StringRef to future-proof against C++23
C++23 will make these conversions ambiguous - so fix them to make the
codebase forward-compatible with C++23 (& a follow-up change I've made
will make this ambiguous/invalid even in <C++23 so we don't regress
this & it generally improves the code anyway)
2021-07-08 13:37:57 -07:00
Georgy Komarov c558b1fca7
[analyzer] Fix calculating offset for fields with an empty type
Fix offset calculation routines in padding checker to avoid assertion
errors described in bugzilla issue 50426. The fields that are subojbects
of zero size, marked with [[no_unique_address]] or empty bitfields will
be excluded from padding calculation routines.

Reviewed By: NoQ

Differential Revision: https://reviews.llvm.org/D104097
2021-07-04 06:57:11 +03:00
Martin Storsjö e5c7c171e5 [clang] Rename StringRef _lower() method calls to _insensitive()
This is mostly a mechanical change, but a testcase that contains
parts of the StringRef class (clang/test/Analysis/llvm-conventions.cpp)
isn't touched.
2021-06-25 00:22:01 +03:00
Balázs Kéri d7227a5bc7 [clang][Analyzer] Track null stream argument in alpha.unix.Stream .
The checker contains check for passing a NULL stream argument.
This change should make more easy to identify where the passed pointer
becomes NULL.

Reviewed By: NoQ

Differential Revision: https://reviews.llvm.org/D104640
2021-06-22 11:16:56 +02:00
Valeriy Savchenko 57006d2f6d [analyzer] Refactor trackExpressionValue to accept TrackingOptions
Differential Revision: https://reviews.llvm.org/D103633
2021-06-11 12:49:04 +03:00
Valeriy Savchenko b6bcf95322 [analyzer] Change FindLastStoreBRVisitor to use Tracker
Additionally, this commit completely removes any uses of
FindLastStoreBRVisitor from the analyzer except for the
one in Tracker.

The next step is actually removing this class altogether
from the header file.

Differential Revision: https://reviews.llvm.org/D103618
2021-06-11 12:49:03 +03:00
Matheus Izvekov aef5d8fdc7 [clang] NFC: Rename rvalue to prvalue
This renames the expression value categories from rvalue to prvalue,
keeping nomenclature consistent with C++11 onwards.

C++ has the most complicated taxonomy here, and every other language
only uses a subset of it, so it's less confusing to use the C++ names
consistently, and mentally remap to the C names when working on that
context (prvalue -> rvalue, no xvalues, etc).

Renames:
* VK_RValue -> VK_PRValue
* Expr::isRValue -> Expr::isPRValue
* SK_QualificationConversionRValue -> SK_QualificationConversionPRValue
* JSON AST Dumper Expression nodes value category: "rvalue" -> "prvalue"

Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>

Reviewed By: rsmith

Differential Revision: https://reviews.llvm.org/D103720
2021-06-09 12:27:10 +02:00
Valeriy Savchenko 92d03c20ea [analyzer] Add forwarding `addVisitor` method
The majority of all `addVisitor` callers follow the same pattern:
  addVisitor(std::make_unique<SomeVisitor>(arg1, arg2, ...));

This patches introduces additional overload for `addVisitor` to simplify
that pattern:
  addVisitor<SomeVisitor>(arg1, arg2, ...);

Differential Revision: https://reviews.llvm.org/D103457
2021-06-03 17:10:16 +03:00
Xuanda Yang 620cef9120 [analyzer] MallocSizeof: sizeof pointer type is compatible with void*
source: https://bugs.llvm.org/show_bug.cgi?id=50214

Make sizeof pointer type compatible with void* in MallocSizeofChecker.

Reviewed By: NoQ

Differential Revision: https://reviews.llvm.org/D103358
2021-05-30 09:51:41 +08:00
Valeriy Savchenko e273918038 [analyzer] Track leaking object through stores
Since we can report memory leaks on one variable, while the originally
allocated object was stored into another one, we should explain
how did it get there.

rdar://76645710

Differential Revision: https://reviews.llvm.org/D100852
2021-04-28 18:37:38 +03:00
Valeriy Savchenko 61ae2db2d7 [analyzer] Adjust the reported variable name in retain count checker
When reporting leaks, we try to attach the leaking object to some
variable, so it's easier to understand.  Before the patch, we always
tried to use the first variable that stored the object in question.
This can get very confusing for the user, if that variable doesn't
contain that object at the moment of the actual leak.  In many cases,
the warning is dismissed as false positive and it is effectively a
false positive when we fail to properly explain the warning to the
user.

This patch addresses the bigest issue in cases like this.  Now we
check if the variable still contains the leaking symbolic object.
If not, we look for the last variable to actually hold it and use
that variable instead.

rdar://76645710

Differential Revision: https://reviews.llvm.org/D100839
2021-04-28 18:37:37 +03:00
Valeriy Savchenko 1dad8c5036 [analyzer][NFC] Remove duplicated work from retain count leak report
Allocation site is the key location for the leak checker.  It is a
uniqueing location for the report and a source of information for
the warning's message.

Before this patch, we calculated and used it twice in bug report and
in bug report visitor.  Such duplication is not only harmful
performance-wise (not much, but still), but also design-wise.  Because
changing something about the end piece of the report should've been
repeated for description as well.

Differential Revision: https://reviews.llvm.org/D100626
2021-04-28 18:37:37 +03:00
Gabor Marton 4b99f9c7db [analyzer][StdLibraryFunctionsChecker] Track dependent arguments
When we report an argument constraint violation, we should track those
other arguments that participate in the evaluation of the violation. By
default, we depend only on the argument that is constrained, however,
there are some special cases like the buffer size constraint that might
be encoded in another argument(s).

Differential Revision: https://reviews.llvm.org/D101358
2021-04-27 15:35:58 +02:00
Gabor Marton a7cb951fa4 [Analyzer][StdLibraryFunctionsChecker] Describe arg constraints
In this patch, I provide a detailed explanation for each argument
constraint. This explanation is added in an extra 'note' tag, which is
displayed alongside the warning.
Since these new notes describe clearly the constraint, there is no need
to provide the number of the argument (e.g. 'Arg3') within the warning.
However, I decided to keep the name of the constraint in the warning (but
this could be a subject of discussion) in order to be able to identify
the different kind of constraint violations easily in a bug database
(e.g. CodeChecker).

Differential Revision: https://reviews.llvm.org/D101060
2021-04-23 17:27:54 +02:00
Valeriy Savchenko 663ac91ed1 [analyzer] Fix false positives in inner pointer checker (PR49628)
This patch supports std::data and std::addressof functions.

rdar://73463300

Differential Revision: https://reviews.llvm.org/D99260
2021-04-08 20:30:12 +03:00
Valeriy Savchenko 9f0d8bac14 [analyzer] Fix dead store checker false positive
It is common to zero-initialize not only scalar variables,
but also structs.  This is also defensive programming and
we shouldn't complain about that.

rdar://34122265

Differential Revision: https://reviews.llvm.org/D99262
2021-04-08 16:12:42 +03:00
Balázs Kéri bee4813789 [clang][Checkers] Fix PthreadLockChecker state cleanup at dead symbol.
It is possible that an entry in 'DestroyRetVal' lives longer
than an entry in 'LockMap' if not removed at checkDeadSymbols.
The added test case demonstrates this.

Reviewed By: NoQ

Differential Revision: https://reviews.llvm.org/D98504
2021-04-06 11:15:29 +02:00
Charusso 9b3df78b4c [analyzer] DynamicSize: Rename 'size' to 'extent' 2021-04-05 19:20:43 +02:00
Charusso 89d210fe1a [analyzer] DynamicSize: Debug facility
This patch adds two debug functions to ExprInspectionChecker to dump out
the dynamic extent and element count of symbolic values:
dumpExtent(), dumpElementCount().
2021-04-05 19:17:52 +02:00
Charusso df64f471d1 [analyzer] DynamicSize: Store the dynamic size
This patch introduces a way to store the size.

Reviewed By: NoQ

Differential Revision: https://reviews.llvm.org/D69726
2021-04-05 19:04:53 +02:00
Balázs Kéri df4fa53fdd [clang][Checkers] Extend PthreadLockChecker state dump (NFC).
Add printing of map 'DestroyRetVal'.

Reviewed By: steakhal

Differential Revision: https://reviews.llvm.org/D98502
2021-04-01 11:59:00 +02:00
Balázs Kéri ffcb4b43b7 Revert "[clang][Checkers] Extend PthreadLockChecker state dump (NFC)."
This reverts commit 49c0ab6d76.

Test failures showed up because non-deterministic output.
2021-03-31 15:28:53 +02:00
Balázs Kéri 49c0ab6d76 [clang][Checkers] Extend PthreadLockChecker state dump (NFC).
Add printing of map 'DestroyRetVal'.

Reviewed By: steakhal

Differential Revision: https://reviews.llvm.org/D98502
2021-03-31 11:19:42 +02:00
Valeriy Savchenko 90377308de [analyzer] Support allocClassWithName in OSObjectCStyleCast checker
`allocClassWithName` allocates an object with the given type.
The type is actually provided as a string argument (type's name).
This creates a possibility for not particularly useful warnings
from the analyzer.

In order to combat with those, this patch checks for casts of the
`allocClassWithName` results to types mentioned directly as its
argument.  All other uses of this method should be reasoned about
as before.

rdar://72165694

Differential Revision: https://reviews.llvm.org/D99500
2021-03-30 15:58:06 +03:00
Artem Dergachev c75b2261a0 [analyzer] Introduce common bug category "Unused code".
This category is generic enough to hold a variety of checkers.
Currently it contains the Dead Stores checker and an alpha unreachable
code checker.

Differential Revision: https://reviews.llvm.org/D98741
2021-03-17 20:58:27 -07:00
Vassil Vassilev 0cb7e7ca0c Make iteration over the DeclContext::lookup_result safe.
The idiom:
```
DeclContext::lookup_result R = DeclContext::lookup(Name);
for (auto *D : R) {...}
```

is not safe when in the loop body we trigger deserialization from an AST file.
The deserialization can insert new declarations in the StoredDeclsList whose
underlying type is a vector. When the vector decides to reallocate its storage
the pointer we hold becomes invalid.

This patch replaces a SmallVector with an singly-linked list. The current
approach stores a SmallVector<NamedDecl*, 4> which is around 8 pointers.
The linked list is 3, 5, or 7. We do better in terms of memory usage for small
cases (and worse in terms of locality -- the linked list entries won't be near
each other, but will be near their corresponding declarations, and we were going
to fetch those memory pages anyway). For larger cases: the vector uses a
doubling strategy for reallocation, so will generally be between half-full and
full. Let's say it's 75% full on average, so there's N * 4/3 + 4 pointers' worth
of space allocated currently and will be 2N pointers with the linked list. So we
break even when there are N=6 entries and slightly lose in terms of memory usage
after that. We suspect that's still a win on average.

Thanks to @rsmith!

Differential revision: https://reviews.llvm.org/D91524
2021-03-17 08:59:04 +00:00
Aaron Puchert 1cb15b10ea Correct Doxygen syntax for inline code
There is no syntax like {@code ...} in Doxygen, @code is a block command
that ends with @endcode, and generally these are not enclosed in braces.
The correct syntax for inline code snippets is @c <code>.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D98665
2021-03-16 15:17:45 +01:00
Adam Balogh bcc662484a [analyzer] Crash fix for alpha.cplusplus.IteratorRange
If the non-iterator side of an iterator operation
`+`, `+=`, `-` or `-=` is `UndefinedVal` an assertions happens.
This small fix prevents this.

Patch by Adam Balogh.

Reviewed By: NoQ

Differential Revision: https://reviews.llvm.org/D85424
2021-03-10 12:42:24 +01:00
Valeriy Savchenko c7635040ce [analyzer] Fix StdLibraryFunctionsChecker performance issue
`initFunctionSummaries` lazily initializes a data structure with
function summaries for standard library functions.  It is called for
every pre-, post-, and eval-call events, i.e. 3 times for each call on
the path.  If the initialization doesn't find any standard library
functions in the translation unit, it will get re-tried (with the same
effect) many times even for small translation units.

For projects not using standard libraries, the speed-up can reach 50%
after this patch.

Differential Revision: https://reviews.llvm.org/D98244
2021-03-10 10:44:04 +03:00
Artem Dergachev 3e206a5922 [analyzer] NFC: Introduce reusable bug category for "C++ move semantics".
Currently only used by MoveChecker but ideally all checkers
should have reusable categories.
2021-01-27 03:39:18 -08:00
Simon Pilgrim 879c12d95a Fix null dereference static analysis warning. NFCI.
Replace cast_or_null<> with cast<> as we immediately dereference the pointer afterward so we're not expecting a null pointer.
2021-01-26 16:19:18 +00:00
Daniel Hwang 8deaec122e [analyzer] Update Fuchsia checker to catch releasing unowned handles.
Certain Fuchsia functions may return handles that are not owned by the
current closure. This adds a check in order to determine when these
handles are released.

Differential Revision: https://reviews.llvm.org/D93868
2021-01-06 16:23:49 -08:00
Barry Revzin 92310454bf Make LLVM build in C++20 mode
Part of the <=> changes in C++20 make certain patterns of writing equality
operators ambiguous with themselves (sorry!).
This patch goes through and adjusts all the comparison operators such that
they should work in both C++17 and C++20 modes. It also makes two other small
C++20-specific changes (adding a constructor to a type that cases to be an
aggregate, and adding casts from u8 literals which no longer have type
const char*).

There were four categories of errors that this review fixes.
Here are canonical examples of them, ordered from most to least common:

// 1) Missing const
namespace missing_const {
    struct A {
    #ifndef FIXED
        bool operator==(A const&);
    #else
        bool operator==(A const&) const;
    #endif
    };

    bool a = A{} == A{}; // error
}

// 2) Type mismatch on CRTP
namespace crtp_mismatch {
    template <typename Derived>
    struct Base {
    #ifndef FIXED
        bool operator==(Derived const&) const;
    #else
        // in one case changed to taking Base const&
        friend bool operator==(Derived const&, Derived const&);
    #endif
    };

    struct D : Base<D> { };

    bool b = D{} == D{}; // error
}

// 3) iterator/const_iterator with only mixed comparison
namespace iter_const_iter {
    template <bool Const>
    struct iterator {
        using const_iterator = iterator<true>;

        iterator();

        template <bool B, std::enable_if_t<(Const && !B), int> = 0>
        iterator(iterator<B> const&);

    #ifndef FIXED
        bool operator==(const_iterator const&) const;
    #else
        friend bool operator==(iterator const&, iterator const&);
    #endif
    };

    bool c = iterator<false>{} == iterator<false>{} // error
          || iterator<false>{} == iterator<true>{}
          || iterator<true>{} == iterator<false>{}
          || iterator<true>{} == iterator<true>{};
}

// 4) Same-type comparison but only have mixed-type operator
namespace ambiguous_choice {
    enum Color { Red };

    struct C {
        C();
        C(Color);
        operator Color() const;
        bool operator==(Color) const;
        friend bool operator==(C, C);
    };

    bool c = C{} == C{}; // error
    bool d = C{} == Red;
}

Differential revision: https://reviews.llvm.org/D78938
2020-12-17 10:44:10 +00:00
Artem Dergachev 8c5ca7c6e6 [analyzer] OSObjectCStyleCast: Improve warning message.
Suggest OSRequiredCast as a closer alternative to C-style cast.
Explain how to decide.
2020-12-10 19:46:33 -08:00
Gabor Marton febe75032f [analyzer][StdLibraryFunctionsChecker] Add more return value contraints
This time, we add contraints to functions that either return with [0, -1] or
with a file descriptor.

Differential Revision: https://reviews.llvm.org/D92771
2020-12-08 17:04:29 +01:00
Gabor Marton d14c631673 [analyzer][StdLibraryFunctionsChecker] Make close and mmap to accept -1 as fd
close:
It is quite often that users chose to call close even if the fd is
negative. Theoretically, it would be nicer to close only valid fds, but
in practice the implementations of close just returns with EBADF in case
of a non-valid fd param. So, we can eliminate many false positives if we
let close to take -1 as an fd. Other negative values are very unlikely,
because open and other fd factories return with -1 in case of failure.

mmap:
In the case of MAP_ANONYMOUS flag (which is supported e.g. in Linux) the
mapping is not backed by any file; its contents are initialized to zero.
The fd argument is ignored; however, some implementations require fd to
be -1 if MAP_ANONYMOUS (or MAP_ANON) is specified, and portable
applications should ensure this.
Consequently, we must allow -1 as the 4th arg.

Differential Revision: https://reviews.llvm.org/D92764
2020-12-08 16:58:30 +01:00
Yu Shan 3ce78f54ed [analyzer] Ignore annotations if func is inlined.
When we annotating a function header so that it could be used by other
TU, we also need to make sure the function is parsed correctly within
the same TU. So if we can find the function's implementation,
ignore the annotations, otherwise, false positive would occur.
Move the escape by value case to post call and do not escape the handle
if the function is inlined and we have analyzed the handle.

Differential Revision: https://reviews.llvm.org/D91902
2020-12-07 11:28:11 -08:00
Gabor Marton b40b3196b3 [analyzer][StdLibraryFunctionsChecker] Add return value constraint to functions with BufferSize
Differential Revision: https://reviews.llvm.org/D92474
2020-12-02 17:54:48 +01:00
Balazs Benics ee073c7985 [analyzer][StdLibraryFunctionsChecker] Fix typos in summaries of mmap and mmap64
The fd parameter of
```
void *mmap(void *addr, size_t length, int prot, int flags, int fd, off_t offset)
```
should be constrained to the range [0, IntMax] as that is of type int.
Constraining to the range [0, Off_tMax] would result in a crash as that is
of a signed type with the value of 0xff..f (-1).

The crash would happen when we try to apply the arg constraints.
At line 583: assert(Min <= Max), as 0 <= -1 is not satisfied

The mmap64 is fixed for the same reason.

Reviewed By: martong, vsavchenko

Differential Revision: https://reviews.llvm.org/D92307
2020-11-30 18:06:28 +01:00
Haowei Wu 914f6c4ff8 [StaticAnalyzer] Support struct annotations in FuchsiaHandleChecker
Support adding handle annotations to sturucture that contains
handles. All the handles referenced by the structure (direct
value or ptr) would be treated as containing the
release/use/acquire annotations directly.

Patch by Yu Shan

Differential Revision: https://reviews.llvm.org/D91223
2020-11-21 19:59:51 -08:00
Artem Dergachev f8f6d6455f Revert "Revert "[analyzer] NFC: Move IssueHash to libAnalysis.""
This reverts commit 662ed9e67a.
2020-11-17 16:01:49 -08:00
Kirstóf Umann 22e7182002 [analyzer][ReturnPtrRangeChecker] Fix a false positive on end() iterator
ReturnPtrRange checker emits a report if a function returns a pointer which
points out of the buffer. However, end() iterator of containers is always such
a pointer, so this always results a false positive report. This false positive
case is now eliminated.

This patch resolves these tickets:
https://bugs.llvm.org/show_bug.cgi?id=20929
https://bugs.llvm.org/show_bug.cgi?id=25226
https://bugs.llvm.org/show_bug.cgi?id=27701

Patch by Tibor Brunner!

Differential Revision: https://reviews.llvm.org/D83678
2020-11-02 16:41:17 +01:00
Simon Pilgrim 2bc2e2e9fe [MallocChecker] Remove duplicate QCoreApplication::postEvent check. NFCI.
This appears to have been in the original patch in D14170.

Reported as "Snippet 11" in https://www.viva64.com/en/b/0771/
2020-10-27 13:14:54 +00:00
Duncan P. N. Exon Smith af4fb416bd clang/StaticAnalyzer: Stop using SourceManager::getBuffer
Update clang/lib/StaticAnalyzer to stop relying on a `MemoryBuffer*`,
using the `MemoryBufferRef` from `getBufferOrNone` or the
`Optional<MemoryBufferRef>` from `getBufferOrFake`, depending on whether
there's logic for checking validity of the buffer. The change to
clang/lib/StaticAnalyzer/Core/IssueHash.cpp is potentially a
functionality change, since the logic was wrong (it checked for
`nullptr`, which was never returned by the old API), but if that was
reachable the new behaviour should be better.

Differential Revision: https://reviews.llvm.org/D89414
2020-10-15 00:34:24 -04:00
Artem Dergachev 662ed9e67a Revert "[analyzer] NFC: Move IssueHash to libAnalysis."
This reverts commit b76dc111dd.
2020-10-13 12:07:28 -07:00
Artem Dergachev b76dc111dd [analyzer] NFC: Move IssueHash to libAnalysis.
IssueHash is an attempt to introduce stable warning identifiers
that won't change when code around them gets moved around.
Path diagnostic consumers print issue hashes for the emitted diagnostics.

This move will allow us to ultimately move path diagnostic consumers
to libAnalysis.

Differential Revision: https://reviews.llvm.org/D67421
2020-10-13 10:53:10 -07:00
Bevin Hansson 101309fe04 [AST] Change return type of getTypeInfoInChars to a proper struct instead of std::pair.
Followup to D85191.

This changes getTypeInfoInChars to return a TypeInfoChars
struct instead of a std::pair of CharUnits. This lets the
interface match getTypeInfo more closely.

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D86447
2020-10-13 13:26:56 +02:00
Nithin Vadukkumchery Rajendrakumar 0b4fe8086f [Analyzer] Fix for dereferece of smart pointer after branching on unknown inner pointer
Summary: Enabling warning after dereferece of smart pointer after branching on unknown inner pointer.

Reviewers: NoQ, Szelethus, vsavchenko, xazax.hun
Reviewed By: NoQ
Subscribers: martong, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D87043
2020-10-09 13:42:25 +02:00
Gabor Marton 11d2e63ab0 [analyzer][StdLibraryFunctionsChecker] Separate the signature from the summaries
The signature should not be part of the summaries as many FIXME comments
suggests. By separating the signature, we open up the way to a generic
matching implementation which could be used later under the hoods of
CallDescriptionMap.

Differential Revision: https://reviews.llvm.org/D88100
2020-09-23 10:59:34 +02:00
Gabor Marton d63a945a13 [analyzer][StdLibraryFunctionsChecker] Fix getline/getdelim signatures
It is no longer needed to add summaries of 'getline' for different
possible underlying types of ssize_t. We can just simply lookup the
type.

Differential Revision: https://reviews.llvm.org/D88092
2020-09-23 10:48:14 +02:00