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4282 Commits

Author SHA1 Message Date
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
Bardia Mahjour 6eff12788e [DDG] Data Dependence Graph - DOT printer - recommit
This is being recommitted to try and address the MSVC complaint.

This patch implements a DDG printer pass that generates a graph in
the DOT description language, providing a more visually appealing
representation of the DDG. Similar to the CFG DOT printer, this
functionality is provided under an option called -dot-ddg and can
be generated in a less verbose mode under -dot-ddg-only option.

Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D90159
2020-12-16 12:37:36 -05:00
Bardia Mahjour a29ecca781 Revert "[DDG] Data Dependence Graph - DOT printer"
This reverts commit fd4a10732c, to
investigate the failure on windows: http://lab.llvm.org:8011/#/builders/127/builds/3274
2020-12-14 16:54:20 -05:00
Bardia Mahjour fd4a10732c [DDG] Data Dependence Graph - DOT printer
This patch implements a DDG printer pass that generates a graph in
the DOT description language, providing a more visually appealing
representation of the DDG. Similar to the CFG DOT printer, this
functionality is provided under an option called -dot-ddg and can
be generated in a less verbose mode under -dot-ddg-only option.

Differential Revision: https://reviews.llvm.org/D90159
2020-12-14 16:41:14 -05:00
Haojian Wu 5663bf201f Revert "[analyzer] NFC: Move path diagnostic consumer implementations to libAnalysis."
The patch introduced a cycle dependency:

clangAnalysis -> clangFrontend -> clangSema -> clangAnalysis

This reverts commit 00ffea77ad.
This reverts commit ea6641085d.
2020-12-11 10:16:13 +01:00
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
Artem Dergachev ea6641085d Revert "Revert "Revert "Revert "[analyzer] NFC: Move path diagnostic consumer implementations to libAnalysis.""""
This reverts commit 6a89cb8136.
2020-12-10 11:02:54 -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
Richard Smith 3fb0879867 Refactor and simplify class scope name lookup.
This is partly in preparation for an upcoming change that can change the
order in which DeclContext lookup results are presented.

In passing, fix some obvious errors where name lookup's notion of a
"static member function" missed static member function templates, and
where its notion of "same set of declarations" was confused by the same
declarations appearing in a different order.
2020-11-25 16:25:33 -08:00
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 6a89cb8136 Revert "Revert "Revert "[analyzer] NFC: Move path diagnostic consumer implementations to libAnalysis."""
This reverts commit 41bcc05e2a.
2020-11-17 18:59:21 -08:00
Artem Dergachev 41bcc05e2a Revert "Revert "[analyzer] NFC: Move path diagnostic consumer implementations to libAnalysis.""
This reverts commit 77bb3ebebb.
2020-11-17 18:45:09 -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
Nathan James d44edfc109
[clang][NFC] Use SmallString instead of SmallVector<char
Simplifies code in some places and is more explicit about what is being used.
No additional includes were added here so no impact on compile time.
2020-11-17 13:02:58 +00:00
Artem Dergachev 499bce3aba Revert "Revert "[analyzer] NFC: Separate PathDiagnosticConsumer options from AnalyzerOptions.""
This reverts commit 10f1ca99b4.

(cherry picked from commit c599fc738a70e482976c6cc0ea31bef561641279)
2020-11-16 14:37:50 -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
Mikhail Maltsev 443ab4d2e0 [clang][Basic] Integrate SourceLocation with FoldingSet, NFCI
This patch removes the necessity to access the SourceLocation internal
representation in several places that use FoldingSet objects.

Reviewed By: dexonsmith

Differential Revision: https://reviews.llvm.org/D69844
2020-10-27 10:43:39 +00:00
Denys Petrov 32efb81ea6 [analyzer] [NFC] Simplify SVal::getAsLocSymbol function using existing functions
Summary: Method of obtaining MemRegion from LocAsInteger/MemRegionVal already exists in SVal::getAsRegion function. Replace repetitive conditions in SVal::getAsLocSymbol with SVal::getAsRegion function.

Differential Revision: https://reviews.llvm.org/D89982
2020-10-26 17:00:29 +02:00
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 10f1ca99b4 Revert "[analyzer] NFC: Separate PathDiagnosticConsumer options from AnalyzerOptions."
This reverts commit fd4b3f123d.
2020-10-13 12:07:36 -07:00
Artem Dergachev 662ed9e67a Revert "[analyzer] NFC: Move IssueHash to libAnalysis."
This reverts commit b76dc111dd.
2020-10-13 12:07:28 -07:00
Artem Dergachev 77bb3ebebb Revert "[analyzer] NFC: Move path diagnostic consumer implementations to libAnalysis."
This reverts commit 44b7cf2983.
2020-10-13 12:03:04 -07:00
Artem Dergachev 44b7cf2983 [analyzer] NFC: Move path diagnostic consumer implementations to libAnalysis.
With this change, we're more or less ready to allow users outside
of the Static Analyzer to take advantage of path diagnostic consumers
for emitting their warnings in different formats.

Differential Revision: https://reviews.llvm.org/D67422
2020-10-13 10:53:10 -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
Artem Dergachev fd4b3f123d [analyzer] NFC: Separate PathDiagnosticConsumer options from AnalyzerOptions.
The AnalyzerOptions object contains too much information that's
entirely specific to the Analyzer. It is also being referenced by
path diagnostic consumers to tweak their behavior. In order for path
diagnostic consumers to function separately from the analyzer,
make a smaller options object that only contains relevant options.

Differential Revision: https://reviews.llvm.org/D67420
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
Bevin Hansson 9fa7f48459 [Fixed Point] Add fixed-point to floating point cast types and consteval.
Reviewed By: leonardchan

Differential Revision: https://reviews.llvm.org/D86631
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
Benjamin Kramer 6a1bca8798 [Analyzer] Fix unused variable warning in Release builds
clang/lib/StaticAnalyzer/Core/ExprEngineCXX.cpp:377:19: warning: unused variable 'Init'
2020-09-25 14:09:43 +02:00
Adam Balogh facad21b29 [Analyzer] Fix for `ExprEngine::computeObjectUnderConstruction()` for base and delegating consturctor initializers
For /C++/ constructor initializers `ExprEngine:computeUnderConstruction()`
asserts that they are all member initializers. This is not neccessarily
true when this function is used to get the return value for the
construction context thus attempts to fetch return values of base and
delegating constructor initializers result in assertions. This small
patch fixes this issue.

Differential Revision: https://reviews.llvm.org/D85351
2020-09-25 13:28:22 +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
Jan Korous 47e6851423 [Analyzer][WebKit] Use tri-state types for relevant predicates
Some of the predicates can't always be decided - for example when a type
definition isn't available. At the same time it's necessary to let
client code decide what to do about such cases - specifically we can't
just use true or false values as there are callees with
conflicting strategies how to handle this.

This is a speculative fix for PR47276.

Differential Revision: https://reviews.llvm.org/D88133
2020-09-22 21:57:24 -07:00
Jan Korous 8a64689e26 [Analyzer][WebKit] UncountedLocalVarsChecker
Differential Review: https://reviews.llvm.org/D83259
2020-09-22 11:05:04 -07:00
Chris Hamilton 2697d138a6 [Analyzer] GNU named variadic macros in Plister
Added support for GNU named variadic macros in
macro expansion for plist generation.

Fix for https://bugs.llvm.org/show_bug.cgi?id=44493

Reviewed By: Szelethus

Differential Revision: https://reviews.llvm.org/D87942
2020-09-21 15:38:28 -05:00
Gabor Marton 0c4f91f84b [analyzer][solver] Fix issue with symbol non-equality tracking
We should track non-equivalency (disequality) in case of greater-then or
less-then assumptions.

Differential Revision: https://reviews.llvm.org/D88019
2020-09-21 16:59:18 +02:00
Kristóf Umann dd1d5488e4 [analyzer][Liveness][NFC] Get rid of statement liveness, because such a thing doesn't exist
The summary and very short discussion in D82122 summarizes whats happening here.

In short, liveness talks about variables, or expressions, anything that
has a value. Well, statements just simply don't have a one.

Differential Revision: https://reviews.llvm.org/D82598
2020-09-15 17:43:02 +02:00
Gabor Marton a012bc4c42 [analyzer][StdLibraryFunctionsChecker] Elaborate the summary of fread and fwrite
Add the BufferSize argument constraint to fread and fwrite. This change
itself makes it possible to discover a security critical case, described
in SEI-CERT ARR38-C.

We also add the not-null constraint on the 3rd arguments.

In this patch, I also remove those lambdas that don't take any
parameters (Fwrite, Fread, Getc), thus making the code better
structured.

Differential Revision: https://reviews.llvm.org/D87081
2020-09-15 16:35:39 +02:00
Balazs Benics cdacffe4ac [analyzer][z3] Use more elaborate Z3 variable names
Previously, it was a tedious task to comprehend Z3 dumps.
We will use the same name prefix just as we use in the corresponding dump method

For all `SymbolData` values:
    `$###` -> `conj_$###`
    `$###` -> `derived_$###`
    `$###` -> `extent_$###`
    `$###` -> `meta_$###`
    `$###` -> `reg_$###`

Reviewed By: xazax.hun,mikhail.ramalho

Differential Revision: https://reviews.llvm.org/D86223
2020-09-14 08:43:56 +02:00
Balazs Benics 163863604f [analyzer] Evaluate PredefinedExpressions
We did not evaluate such expressions, just returned `Unknown` for such cases.
After this patch, we will be able to access a unique value identifying a template instantiation via the value of the `PRETTY_FUNCTION` predefined expression.

Reviewed By: vsavchenko

Differential Revision: https://reviews.llvm.org/D87004
2020-09-14 08:43:56 +02:00
Vitaly Buka a8503b87f7 [NFC] Remove unused static function 2020-09-11 16:50:30 -07:00
Kristóf Umann b9bca883c9 [analyzer][NFC] Don't bind values to ObjCForCollectionStmt, replace it with a GDM trait
Based on the discussion in D82598#2171312. Thanks @NoQ!

D82598 is titled "Get rid of statement liveness, because such a thing doesn't
exist", and indeed, expressions express a value, non-expression statements
don't.

if (a && get() || []{ return true; }())
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ has a value
    ~ has a value
    ~~~~~~~~~~ has a value
                  ~~~~~~~~~~~~~~~~~~~~ has a value
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ doesn't have a value

That is simple enough, so it would only make sense if we only assigned symbolic
values to expressions in the static analyzer. Yet the interface checkers can
access presents, among other strange things, the following two methods:

ProgramState::BindExpr(const Stmt *S, const LocationContext *LCtx, SVal V,
                       bool Invalidate=true)
ProgramState::getSVal(const Stmt *S, const LocationContext *LCtx)

So, what gives? Turns out, we make an exception for ReturnStmt (which we'll
leave for another time) and ObjCForCollectionStmt. For any other loops, in order
to know whether we should analyze another iteration, among other things, we
evaluate it's condition. Which is a problem for ObjCForCollectionStmt, because
it simply doesn't have one (CXXForRangeStmt has an implicit one!). In its
absence, we assigned the actual statement with a concrete 1 or 0 to indicate
whether there are any more iterations left. However, this is wildly incorrect,
its just simply not true that the for statement has a value of 1 or 0, we can't
calculate its liveness because that doesn't make any sense either, so this patch
turns it into a GDM trait.

Fixing this allows us to reinstate the assert removed in
https://reviews.llvm.org/rG032b78a0762bee129f33e4255ada6d374aa70c71.

Differential Revision: https://reviews.llvm.org/D86736
2020-09-11 15:58:48 +02:00
Kristóf Umann be0d79f329 [analyzer][MacroExpansion] Fix a crash where multiple parameters resolved to __VA_ARGS__
In short, macro expansions handled the case where a variadic parameter mapped to
multiple arguments, but not the other way around. An internal ticket was
submitted that demonstrated that we fail an assertion. Macro expansion so far
worked by lexing the source code token-by-token and using the Preprocessor to
turn these tokens into identifiers or just get their proper spelling, but what
this counter intuitively doesn't do, is actually expand these macros, so we have
to do the heavy lifting -- in this case, figure out what __VA_ARGS__ expands
into. Since this case can only occur in a nested macro, the information we
gathered from the containing macro does contain this information. If a parameter
resolves to __VA_ARGS__, we need to temporarily stop getting our tokens from the
lexer, and get the tokens from what __VA_ARGS__ maps to.

Differential Revision: https://reviews.llvm.org/D86135
2020-09-11 14:07:58 +02:00
Kirstóf Umann 26d9a94681 [analyzer][MacroExpansion][NFC] Fix incorrectly calling parameters arguments 2020-09-11 13:33:02 +02:00
Kirstóf Umann 1c08da3867 [analyzer][MacroExpansion] Add a few dumps functions 2020-09-11 13:29:14 +02:00