Summary:
Outputs from an asm goto block cannot be used on the indirect branch.
It's not supported and may result in invalid code generation.
Reviewers: jyknight, nickdesaulniers, hfinkel
Reviewed By: nickdesaulniers
Subscribers: martong, cfe-commits, rnk, craig.topper, hiraditya, rsmith
Tags: #clang
Differential Revision: https://reviews.llvm.org/D71314
Summary:
According to documentations, after an `fclose` call any other stream
operations cause undefined behaviour, regardless if the close failed
or not.
This change adds the check for the opened state before all other
(applicable) operations.
Reviewers: Szelethus
Reviewed By: Szelethus
Subscribers: xazax.hun, baloghadamsoftware, szepet, a.sidorin, mikhail.ramalho, Szelethus, donat.nagy, dkrupp, gamesh411, Charusso, martong, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D75614
The output of subprocess.check_output is decode()'d through the rest of
this python program, but one appears to have been missed for the output
of the call to "clang -print-file-name=include".
On Windows, with Python 3.6, this leads to the 'args' array being a mix of
bytes and strings, which causes exceptions later down the line.
I can't easily test with python2 on Windows, but python2 on Ubuntu 18.04
was happy with this change.
Summary: The new way of checking fix-its is `%check_analyzer_fixit`.
Reviewed By: NoQ, Szelethus, xazax.hun
Differential Revision: https://reviews.llvm.org/D73729
Summary:
This patch introduces a way to apply the fix-its by the Analyzer:
`-analyzer-config apply-fixits=true`.
The fix-its should be testable, therefore I have copied the well-tested
`check_clang_tidy.py` script. The idea is that the Analyzer's workflow
is different so it would be very difficult to use only one script for
both Tidy and the Analyzer, the script would diverge a lot.
Example test: `// RUN: %check-analyzer-fixit %s %t -analyzer-checker=core`
When the copy-paste happened the original authors were:
@alexfh, @zinovy.nis, @JonasToth, @hokein, @gribozavr, @lebedev.ri
Reviewed By: NoQ, alexfh, zinovy.nis
Differential Revision: https://reviews.llvm.org/D69746
Summary:
This patch introduces the `clang_analyzer_isTainted` expression inspection
check for checking taint.
Using this we could query the analyzer whether the expression used as the
argument is tainted or not. This would be useful in tests, where we don't want
to issue warning for all tainted expressions in a given file
(like the `debug.TaintTest` would do) but only for certain expressions.
Example usage:
```lang=c++
int read_integer() {
int n;
clang_analyzer_isTainted(n); // expected-warning{{NO}}
scanf("%d", &n);
clang_analyzer_isTainted(n); // expected-warning{{YES}}
clang_analyzer_isTainted(n + 2); // expected-warning{{YES}}
clang_analyzer_isTainted(n > 0); // expected-warning{{YES}}
int next_tainted_value = n; // no-warning
return n;
}
```
Reviewers: NoQ, Szelethus, baloghadamsoftware, xazax.hun, boga95
Reviewed By: Szelethus
Subscribers: martong, rnkovacs, whisperity, xazax.hun,
baloghadamsoftware, szepet, a.sidorin, mikhail.ramalho, donat.nagy,
Charusso, cfe-commits, boga95, dkrupp, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D74131
Summary:
Right now we annotate C++'s `operator new` with `noalias` attribute,
which very much is healthy for optimizations.
However as per [[ http://eel.is/c++draft/basic.stc.dynamic.allocation | `[basic.stc.dynamic.allocation]` ]],
there are more promises on global `operator new`, namely:
* non-`std::nothrow_t` `operator new` *never* returns `nullptr`
* If `std::align_val_t align` parameter is taken, the pointer will also be `align`-aligned
* ~~global `operator new`-returned pointer is `__STDCPP_DEFAULT_NEW_ALIGNMENT__`-aligned ~~ It's more caveated than that.
Supplying this information may not cause immediate landslide effects
on any specific benchmarks, but it for sure will be healthy for optimizer
in the sense that the IR will better reflect the guarantees provided in the source code.
The caveat is `-fno-assume-sane-operator-new`, which currently prevents emitting `noalias`
attribute, and is automatically passed by Sanitizers ([[ https://bugs.llvm.org/show_bug.cgi?id=16386 | PR16386 ]]) - should it also cover these attributes?
The problem is that the flag is back-end-specific, as seen in `test/Modules/explicit-build-flags.cpp`.
But while it is okay to add `noalias` metadata in backend, we really should be adding at least
the alignment metadata to the AST, since that allows us to perform sema checks on it.
Reviewers: erichkeane, rjmccall, jdoerfert, eugenis, rsmith
Reviewed By: rsmith
Subscribers: xbolva00, jrtc27, atanasyan, nlopes, cfe-commits
Tags: #llvm, #clang
Differential Revision: https://reviews.llvm.org/D73380
So far we've been dropping coverage every time we've encountered
a CXXInheritedCtorInitExpr. This patch attempts to add some
initial support for it.
Constructors for arguments of a CXXInheritedCtorInitExpr are still
not fully supported.
Differential Revision: https://reviews.llvm.org/D74735
Exactly what it says on the tin! I decided not to merge this with the patch that
changes all these to a CallDescriptionMap object, so the patch is that much more
trivial.
Differential Revision: https://reviews.llvm.org/D68163
Currently, using negative numbers in iterator operations (additions and
subractions) results in advancements with huge positive numbers due to
an error. This patch fixes it.
Differential Revision: https://reviews.llvm.org/D74760
Summary:
Clang's "asm goto" feature didn't initially support outputs constraints. That
was the same behavior as gcc's implementation. The decision by gcc not to
support outputs was based on a restriction in their IR regarding terminators.
LLVM doesn't restrict terminators from returning values (e.g. 'invoke'), so
it made sense to support this feature.
Output values are valid only on the 'fallthrough' path. If an output value's used
on an indirect branch, then it's 'poisoned'.
In theory, outputs *could* be valid on the 'indirect' paths, but it's very
difficult to guarantee that the original semantics would be retained. E.g.
because indirect labels could be used as data, we wouldn't be able to split
critical edges in situations where two 'callbr' instructions have the same
indirect label, because the indirect branch's destination would no longer be
the same.
Reviewers: jyknight, nickdesaulniers, hfinkel
Reviewed By: jyknight, nickdesaulniers
Subscribers: MaskRay, rsmith, hiraditya, llvm-commits, cfe-commits, craig.topper, rnk
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D69876
Summary:
This patch introduces a new checker:
`alpha.security.cert.pos.34c`
This checker is implemented based on the following rule:
https://wiki.sei.cmu.edu/confluence/x/6NYxBQ
The check warns if `putenv` function is
called with automatic storage variable as an argument.
Differential Revision: https://reviews.llvm.org/D71433
This is useful for performing custom build system integration that works by appending '--analyze --analyzer-output html' to all clang build commands.
For such users there is now still a way to have the fancy index.html file
in the output.
Differential Revision: https://reviews.llvm.org/D74467
In the path-sensitive vfork() checker that keeps a list of operations
allowed after a successful vfork(), unforget to include execve() in the list.
Patch by Jan Včelák!
Differential Revision: https://reviews.llvm.org/D73629
Converting a pointer to an integer whose result cannot represented in the
integer type is undefined behavior is C and prohibited in C++. C++ already
has a diagnostic when casting. This adds a diagnostic for C.
Since this diagnostic uses the range of the conversion it also modifies
int-to-pointer-cast diagnostic to use a range.
Fixes PR8718: No warning on casting between pointer and non-pointer-sized int
Differential Revision: https://reviews.llvm.org/D72231
Summary:
Both EOF and the max value of unsigned char is platform dependent. In this
patch we try our best to deduce the value of EOF from the Preprocessor,
if we can't we fall back to -1.
Reviewers: Szelethus, NoQ
Subscribers: whisperity, xazax.hun, kristof.beyls, baloghadamsoftware, szepet, rnkovacs, a.sidorin, mikhail.ramalh
Tags: #clang
Differential Revision: https://reviews.llvm.org/D74473
Summary:
Due to a recent (but retroactive) C++ rule change, only sufficiently
C-compatible classes are permitted to be given a typedef name for
linkage purposes. Add an enabled-by-default warning for these cases, and
rephrase our existing error for the case where we encounter the typedef
name for linkage after we've already computed and used a wrong linkage
in terms of the new rule.
Reviewers: rjmccall
Subscribers: cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D74103
STL Algorithms are usually implemented in a tricky for performance
reasons which is too complicated for the analyzer. Furthermore inlining
them is costly. Instead of inlining we should model their behavior
according to the specifications.
This patch is the first step towards STL Algorithm modeling. It models
all the `find()`-like functions in a simple way: the result is either
found or not. In the future it can be extended to only return success if
container modeling is also extended in a way the it keeps track of
trivial insertions and deletions.
Differential Revision: https://reviews.llvm.org/D70818
The tool is now looked for in the source directory rather than in the
install directory, which should exclude the problems with not being able
to find it.
The tests still aren't being run on Windows, but they hopefully will run
on other platforms that have shell, which hopefully also means Perl.
Differential Revision: https://reviews.llvm.org/D69781
Iterator modeling depends on container modeling,
but not vice versa. This enables the possibility
to arrange these two modeling checkers into
separate layers.
There are several advantages for doing this: the
first one is that this way we can keep the
respective modeling checkers moderately simple
and small. Furthermore, this enables creation of
checkers on container operations which only
depend on the container modeling. Thus iterator
modeling can be disabled together with the
iterator checkers if they are not needed.
Since many container operations also affect
iterators, container modeling also uses the
iterator library: it creates iterator positions
upon calling the `begin()` or `end()` method of
a containter (but propagation of the abstract
position is left to the iterator modeling),
shifts or invalidates iterators according to the
rules upon calling a container modifier and
rebinds the iterator to a new container upon
`std::move()`.
Iterator modeling propagates the abstract
iterator position, handles the relations between
iterator positions and models iterator
operations such as increments and decrements.
Differential Revision: https://reviews.llvm.org/D73547
These are mostly trivial additions as both of them are reusing existing
PThreadLockChecker logic. I only needed to add the list of functions to
check and do some plumbing to make sure that we display the right
checker name in the diagnostic.
Differential Revision: https://reviews.llvm.org/D73376
Summary:
This checker verifies if default placement new is provided with pointers
to sufficient storage capacity.
Noncompliant Code Example:
#include <new>
void f() {
short s;
long *lp = ::new (&s) long;
}
Based on SEI CERT rule MEM54-CPP
https://wiki.sei.cmu.edu/confluence/display/cplusplus/MEM54-CPP.+Provide+placement+new+with+properly+aligned+pointe
This patch does not implement checking of the alignment.
Reviewers: NoQ, xazax.hun
Subscribers: mgorny, whisperity, xazax.hun, baloghadamsoftware, szepet,
rnkovacs, a.sidorin, mikhail.ramalho, donat
Tags: #clang
Differential Revision: https://reviews.llvm.org/D71612
Method '-[NSCoder decodeValueOfObjCType:at:]' is not only deprecated
but also a security hazard, hence a loud check.
Differential Revision: https://reviews.llvm.org/D71728
MallocChecker warns when memory is passed into -[NSData initWithBytesNoCopy]
but isn't allocated by malloc(), because it will be deallocated by free().
However, initWithBytesNoCopy has an overload that takes an arbitrary block
for deallocating the object. If such overload is used, it is no longer
necessary to make sure that the memory is allocated by malloc().
This is useful for clients that are relying on linearized CFGs for evaluating
subexpressions and want the default initializer to be evaluated properly.
The upcoming lifetime analysis is using this but it might also be useful
for the static analyzer at some point.
Differential Revision: https://reviews.llvm.org/D71642
This canonicalizes the representation of unknown pointer symbols,
which reduces the overall confusion in pointer cast representation.
Patch by Vince Bridgers!
Differential Revision: https://reviews.llvm.org/D70836
Bill Wendling