Akira Hatanaka [Fri, 2 Mar 2018 01:53:15 +0000 (01:53 +0000)]
Add an option to disable tail-call optimization for escaping blocks.
This makes it easier to debug crashes and hangs in block functions since
users can easily find out where the block is called from. The option
doesn't disable tail-calls from non-escaping blocks since non-escaping
blocks are not as hard to debug as escaping blocks.
Always set dso_local in CodeGenModule::setDSOLocal.
This shouldn't change any results for now, but is more consistent with
how we set dllimport/dllexport and will make future changes easier.
Since clang produces IR as it parses, it can find out mid file that
something is dllimport. When that happens we have to drop
dso_local. This is not a problem right now because
CodeGenModule::setDSOLocal is called from relatively few places at
the moment.
Turns out, the type passed for the lambda capture was incorrect.
One more argument to abandon the getSVal overload which does not require the
type information.
David L. Jones [Fri, 2 Mar 2018 00:07:45 +0000 (00:07 +0000)]
[NFC] Move CommentOpts checks to the call sites that depend on it. (Re-applying r326501.)
When parsing comments, for example, for -Wdocumentation, slightly different
behaviour occurs when -fparse-all-comments is specified. However, these
differences are subtle:
1. All comments are saved during parsing, regardless of whether they are doc
comments or not.
2. "Maybe-doc" comments, like <, !, etc, are saved as such, instead of marking
them as ordinary comments. The maybe-doc type of comment is never saved
otherwise. (Warning on these is the impetus of -Wdocumentation.)
3. All comments are treated as doc comments in ASTContext, even if they are ordinary.
This change moves the logic for checking CommentOptions.ParseAllComments closer
to where it has an effect. The overall logic is unchanged, but checks of the
ParseAllComments flag are now done where the effect will be clearer.
David L. Jones [Thu, 1 Mar 2018 23:14:00 +0000 (23:14 +0000)]
Revert r326501 due to buildbot breakage.
Original change:
[NFC] Move CommentOpts checks to the call sites that depend on it.
When parsing comments, for example, for -Wdocumentation, slightly different
behaviour occurs when -fparse-all-comments is specified. However, these
differences are subtle:
1. All comments are saved during parsing, regardless of whether they are doc comments or not.
2. "Maybe-doc" comments, like //<, //!, etc, are saved as such, instead of marking them as ordinary comments. The maybe-doc type of comment is never saved otherwise. (Warning on these is the impetus of -Wdocumentation.)
3. All comments are treated as doc comments in ASTContext, even if they are ordinary.
This change moves the logic for checking CommentOptions.ParseAllComments closer
to where it has an effect. The overall logic is unchanged, but checks of the
ParseAllComments flag are now done where the effect will be clearer.
David L. Jones [Thu, 1 Mar 2018 22:41:53 +0000 (22:41 +0000)]
[NFC] Move CommentOpts checks to the call sites that depend on it.
When parsing comments, for example, for -Wdocumentation, slightly different
behaviour occurs when -fparse-all-comments is specified. However, these
differences are subtle:
1. All comments are saved during parsing, regardless of whether they are doc
comments or not.
2. "Maybe-doc" comments, like //<, //!, etc, are saved as such, instead of
marking them as ordinary comments. The maybe-doc type of comment is never
saved otherwise. (Warning on these is the impetus of -Wdocumentation.)
3. All comments are treated as doc comments in ASTContext, even if they are
ordinary.
This change moves the logic for checking CommentOptions.ParseAllComments closer
to where it has an effect. The overall logic is unchanged, but checks of the
ParseAllComments flag are now done where the effect will be clearer.
Chih-Hung Hsieh [Thu, 1 Mar 2018 22:26:19 +0000 (22:26 +0000)]
[Driver] Pass -f[no-]emulated-tls and set up ExplicitEmulatedTLS
Since LLVM r326341, default EmulatedTLS mode is decided in backend
according to target triple. Any front-end should pass -f[no]-emulated-tls
to backend and set up ExplicitEmulatedTLS only when the flags are used.
Martin Storsjo [Thu, 1 Mar 2018 20:22:57 +0000 (20:22 +0000)]
[RecordLayout] Only assert that fundamental type sizes are power of two on MSVC
Make types with sizes that aren't a power of two an error (that can
be disabled) in structs with ms_struct layout, except on mingw where
the situation is quite likely to occur and GCC handles it silently.
Ilya Biryukov [Thu, 1 Mar 2018 14:54:16 +0000 (14:54 +0000)]
Resubmit [analyzer] Support for naive cross translation unit analysis
Originally submitted as r326323 and r326324.
Reverted in r326432.
Reverting the commit was a mistake.
The breakage was due to invalid build files in our internal buildsystem,
CMakeLists did not have any cyclic dependencies.
Summary:
When disabled, this option allows removing the space before colon,
making it act more like the semi-colon. When enabled (default), the
current behavior is not affected.
This mostly affects C++11 loop, initializer list, inheritance list and
container literals:
class Foo: Bar {}
Foo::Foo(): a(a) {}
for (auto i: myList) {}
f({a: 1, b: 2, c: 3});
Serge Pavlov [Thu, 1 Mar 2018 07:04:11 +0000 (07:04 +0000)]
Function definition may have uninstantiated body
Current implementation of `FunctionDecl::isDefined` does not take into
account redeclarations that do not have bodies, but the bodies can be
instantiated from corresponding templated definition. This behavior does
not allow to detect function redefinition in the cases where friend
functions is defined in class templates. For instance, the code:
```
template<typename T> struct X { friend void f() {} };
X<int> xi;
void f() {}
```
compiles successfully but must fail due to redefinition of `f`. The
declaration of the friend `f` is created when the containing template
`X` is instantiated, but it does not have a body as per 14.5.4p4
because `f` is not odr-used.
With this change the function `Sema::CheckForFunctionRedefinition`
considers functions with uninstantiated bodies as definitions.
So I wrote a clang-tidy check to lint out redundant `isa`, `cast`, and
`dyn_cast`s for fun. This is a portion of what it found for clang; I
plan to do similar cleanups in LLVM and other subprojects when I find
time.
Because of the volume of changes, I explicitly avoided making any change
that wasn't highly local and obviously correct to me (e.g. we still have
a number of foo(cast<Bar>(baz)) that I didn't touch, since overloading
is a thing and the cast<Bar> did actually change the type -- just up the
class hierarchy).
I also tried to leave the types we were cast<>ing to somewhere nearby,
in cases where it wasn't locally obvious what we were dealing with
before.
Artem Dergachev [Thu, 1 Mar 2018 01:27:46 +0000 (01:27 +0000)]
[analyzer] Add a checker for mmap()s which are both writable and executable.
This is a security check that warns when both PROT_WRITE and PROT_EXEC are
set during mmap(). If mmap()ed memory is both writable and executable, it makes
it easier for the attacker to execute arbitrary code when contents of this
memory are compromised. Some applications require such mmap()s though, such as
different sorts of JIT.
Re-applied after a revert in r324167.
Temporarily stays in the alpha package because it needs a better way of
determining macro values that are not immediately available in the AST.
Artem Dergachev [Thu, 1 Mar 2018 01:09:24 +0000 (01:09 +0000)]
[CFG] [analyzer] Recall that we only skip NoOp casts in construction contexts.
For now. We should also add support for ConstructorConversion casts as presented
in the attached test case, but this requires more changes because AST around
them seems different.
The check was originally present but was accidentally lost during r326021.
Start setting dllimport/dllexport in setGVProperties.
This is the next step in setting dso_local for COFF.
The patches changes setGVProperties to first set dllimport/dllexport
and changes a few cases that were setting dllimport/dllexport
manually. With this a few more GVs are marked dso_local.
CodeGenObjCXX: handle inalloca appropriately for msgSend variant
objc_msgSend_stret takes a hidden parameter for the returned structure's
address for the construction. When the function signature is rewritten
for the inalloca passing, the return type is no longer marked as
indirect but rather inalloca stret. This enhances the test for the
indirect return to check for that case as well. This fixes the
incorrect return classification for Windows x86.
Nico Weber [Wed, 28 Feb 2018 19:49:07 +0000 (19:49 +0000)]
[clang-cl] Implement /X
/X makes cl stop looking in %INCLUDE%. Implement this for clang-cl.
As it turns out, the return in ToolChains/MSVC.cpp, AddClangSystemIncludeArgs()
for -nostdlibinc is already in the right place (but -nostdlibinc isn't exposed
by clang-cl), so just alias /X to that.
Gabor Horvath [Wed, 28 Feb 2018 13:23:10 +0000 (13:23 +0000)]
[analyzer] Support for naive cross translation unit analysis
The aim of this patch is to be minimal to enable incremental development of
the feature on the top of the tree. This patch should be an NFC when the
feature is turned off. It is turned off by default and still considered as
experimental.
Technical details are available in the EuroLLVM Talk:
http://llvm.org/devmtg/2017-03//2017/02/20/accepted-sessions.html#7
Note that the initial prototype was done by A. Sidorin et al.: http://lists.llvm.org/pipermail/cfe-dev/2015-October/045730.html
Contributions to the measurements and the new version of the code: Peter Szecsi, Zoltan Gera, Daniel Krupp, Kareem Khazem.
Akira Hatanaka [Wed, 28 Feb 2018 07:15:55 +0000 (07:15 +0000)]
[ObjC] Allow declaring __strong pointer fields in structs in Objective-C
ARC mode.
Declaring __strong pointer fields in structs was not allowed in
Objective-C ARC until now because that would make the struct non-trivial
to default-initialize, copy/move, and destroy, which is not something C
was designed to do. This patch lifts that restriction.
Special functions for non-trivial C structs are synthesized that are
needed to default-initialize, copy/move, and destroy the structs and
manage the ownership of the objects the __strong pointer fields point
to. Non-trivial structs passed to functions are destructed in the callee
function.
Richard Smith [Wed, 28 Feb 2018 03:02:23 +0000 (03:02 +0000)]
Fix a couple of cases where we would fail to correctly parse deduced class template specialization types.
Specifically, we would not properly parse these types within template arguments
(for non-type template parameters), and in tentative parses. Fixing both of
these essentially requires that we parse deduced template specialization types
as types in all contexts, even in template argument lists -- in particular,
tentative parsing may look ahead and annotate a deduced template specialization
type before we figure out that we're actually supposed to treat the tokens as a
template-name. We deal with this by simply permitting deduced template
specialization types when parsing template arguments, and converting them to
template template arguments.
Artem Dergachev [Tue, 27 Feb 2018 22:05:55 +0000 (22:05 +0000)]
[analyzer] UndefinedAssignmentChecker: Better warning message in implicit ctors.
When a class forgets to initialize a field in the constructor, and then gets
copied around, a warning is emitted that the value assigned to a specific field
is undefined.
When the copy/move constructor is implicit (not written out in the code) but not
trivial (is not a trivial memory copy, eg. because members have an explicit copy
constructor), the body of such constructor is auto-generated in the AST.
In this case the checker's warning message is squeezed at the top of
the class declaration, and it gets hard to guess which field is at fault.
Fix the warning message to include the name of the field.
- Expand GK_*s (i.e. GFX6 -> GFX600, GFX601, etc.)
- This allows us to choose features correctly in some cases (for example, fast fmaf is available on gfx600, but not gfx601)
- Move HasFMAF, HasFP64, HasLDEXPF to GPUInfo tables
- Add HasFastFMA, HasFastFMAF to GPUInfo tables
- Add missing tests
Artem Dergachev [Tue, 27 Feb 2018 21:19:33 +0000 (21:19 +0000)]
[analyzer] MallocChecker: Suppress false positives in shared pointers.
Throw away MallocChecker warnings that occur after releasing a pointer within a
destructor (or its callees) after performing C11 atomic fetch_add or fetch_sub
within that destructor (or its callees).
This is an indication that the destructor's class is likely a
reference-counting pointer. The analyzer is not able to understand that the
original reference count is usually large enough to avoid most use-after-frees.
Even when the smart pointer is a local variable, we still have these false
positives that this patch suppresses, because the analyzer doesn't currently
support atomics well enough.
Artem Dergachev [Tue, 27 Feb 2018 21:10:08 +0000 (21:10 +0000)]
[analyzer] Fix trivial copy for empty objects.
The SVal for any empty C++ object is an UnknownVal. Because RegionStore does
not have binding extents, binding an empty object to an UnknownVal may
potentially overwrite existing bindings at the same offset.
Therefore, when performing a trivial copy of an empty object, don't try to
take the value of the object and bind it to the copy. Doing nothing is accurate
enough, and it doesn't screw any existing bindings.
Artem Dergachev [Tue, 27 Feb 2018 21:02:58 +0000 (21:02 +0000)]
[analyzer] Track temporaries without construction contexts for destruction.
Sometimes it is not known at compile time which temporary objects will be
constructed, eg. 'x ? A() : B()' or 'C() || D()'. In this case we track which
temporary was constructed to know how to properly call the destructor.
Once the construction context for temporaries was introduced, we moved the
tracking code to the code that investigates the construction context.
Bring back the old mechanism because construction contexts are not always
available yet - eg. in the case where a temporary is constructed without a
constructor expression, eg. returned from a function by value. The mechanism
should still go away eventually.
Additionally, fix a bug in the temporary cleanup code for the case when
construction contexts are not available, which could lead to temporaries
staying in the program state and increasing memory consumption.
Artem Dergachev [Tue, 27 Feb 2018 20:54:40 +0000 (20:54 +0000)]
[analyzer] Don't crash when dynamic type of a variable is set via placement new.
If a variable or an otherwise a concrete typed-value region is being
placement-new'ed into, its dynamic type may change in arbitrary manners. And
when the region is used, there may be a third type that's different from both
the static and the dynamic type. It cannot be *completely* different from the
dynamic type, but it may be a base class of the dynamic type - and in this case
there isn't (and shouldn't be) any indication anywhere in the AST that there is
a derived-to-base cast from the dynamic type to the third type.
Perform a generic cast (evalCast()) from the third type to the dynamic type
in this case. From the point of view of the SVal hierarchy, this would have
produced non-canonical SVals if we used such generic cast in the normal case,
but in this case there doesn't seem to be a better option.
Artem Dergachev [Tue, 27 Feb 2018 20:03:35 +0000 (20:03 +0000)]
[CFG] NFC: Refactor ConstructionContext into a finite set of cases.
ConstructionContext is moved into a separate translation unit and is separated
into multiple classes. The "old" "raw" ConstructionContext is renamed into
ConstructionContextLayer - which corresponds to the idea of building the context
gradually layer-by-layer, but it isn't easy to use in the clients. Once
CXXConstructExpr is reached, layers that we've gathered so far are transformed
into the actual, "new-style" "flat" ConstructionContext, which is put into the
CFGConstructor element and has no layers whatsoever (until it actually needs
them, eg. aggregate initialization). The new-style ConstructionContext is
instead presented as a variety of sub-classes that enumerate different ways of
constructing an object in C++. There are 5 of these supported for now,
which is around a half of what needs to be supported.
The layer-by-layer buildup process is still a little bit weird, but it hides
all the weirdness in one place, that sounds like a good thing.
Artem Dergachev [Tue, 27 Feb 2018 19:47:49 +0000 (19:47 +0000)]
[analyzer] Introduce correct lifetime extension behavior in simple cases.
This patch uses the reference to MaterializeTemporaryExpr stored in the
construction context since r326014 in order to model that expression correctly.
When modeling MaterializeTemporaryExpr, instead of copying the raw memory
contents from the sub-expression's rvalue to a completely new temporary region,
that we conjure up for the lack of better options, we now have the better
option to recall the region into which the object was originally constructed
and declare that region to be the value of the expression, which is semantically
correct.
This only works when the construction context is available, which is worked on
independently.
The temporary region's liveness (in the sense of removeDeadBindings) is extended
until the MaterializeTemporaryExpr is resolved, in order to keep the store
bindings around, because it wouldn't be referenced from anywhere else in the
program state.
George Karpenkov [Tue, 27 Feb 2018 19:28:52 +0000 (19:28 +0000)]
[analyzer] Only attempt to get the value of locations of known type
Fixes https://bugs.llvm.org/show_bug.cgi?id=36474
In general, getSVal API should be changed so that it does not crash on
some non-obvious conditions.
It should either be updated to require a type, or to return Optional<SVal>.
Summary: This fixes a glitch where ``operator: value`` in a text proto would mess up the underlying formatting since it gets parsed as a kw_operator instead of an identifier.
Roman Lebedev [Tue, 27 Feb 2018 15:54:55 +0000 (15:54 +0000)]
Revert "[Tooling] [0/1] Refactor FrontendActionFactory::create() to return std::unique_ptr<>"
This reverts commit rL326201
This broke gcc4.8 builds, compiler just segfaults:¬
http://lab.llvm.org:8011/builders/clang-atom-d525-fedora-rel/builds/14909¬
http://lab.llvm.org:8011/builders/clang-x86_64-linux-abi-test/builds/22673¬
Roman Lebedev [Tue, 27 Feb 2018 15:19:20 +0000 (15:19 +0000)]
[Tooling] [0/1] Refactor FrontendActionFactory::create() to return std::unique_ptr<>
Summary:
Noticed during review of D41102.
I'm not sure whether there are any principal reasons why it returns raw owning pointer,
or it is just a old code that was not updated post-C++11.
I'm not too sure what testing i should do, because `check-all` is not error clean here for some reason,
but it does not //appear// asif those failures are related to these changes.
This is clang part.
Clang-tools-extra part is D43780.
Francois Ferrand [Tue, 27 Feb 2018 13:48:27 +0000 (13:48 +0000)]
clang-format: use AfterControlStatement to format ObjC control blocks
ObjC defines `@autoreleasepool` and `@synchronized` control blocks. These
used to be formatted according to the `AfterObjCDeclaration` brace-
wrapping flag, which is not very consistent.
This patch changes the behavior to use the `AfterControlStatement` flag
instead. This should not affect the behavior unless a custom brace
wrapping mode is used.
Francois Ferrand [Tue, 27 Feb 2018 13:48:21 +0000 (13:48 +0000)]
clang-format: fix formatting of ObjC @synchronized blocks
Summary:
The blocks used to be formatted using the "default" behavior, and would
thus be mistaken for function calls followed by blocks: this could lead
to unexpected inlining of the block and extra line-break before the
opening brace.
They are now formatted similarly to `@autoreleasepool` blocks, as
expected:
Martin Storsjo [Tue, 27 Feb 2018 06:27:06 +0000 (06:27 +0000)]
[RecordLayout] Don't align to non-power-of-2 sizes when using -mms-bitfields
When targeting GNU/MinGW for i386, the size of the "long double" data
type is 12 bytes (while it is 8 bytes in MSVC). When building
with -mms-bitfields to have struct layouts match MSVC, data types
are laid out in a struct with alignment according to their size.
However, this doesn't make sense for the long double type, since
it doesn't match MSVC at all, and aligning to a non-power-of-2
size triggers other asserts later.
This matches what GCC does, aligning a long double to 4 bytes
in structs on i386 even when -mms-bitfields is specified.
This fixes asserts when using the max_align_t data type when
building for MinGW/i386 with the -mms-bitfields flag.
Shoaib Meenai [Tue, 27 Feb 2018 06:04:23 +0000 (06:04 +0000)]
[Driver] Fix codeview-column-info on macOS
macOS home directory paths begin with /Users, and clang-cl interprets
the /U portion as a macro undefine rather than a path, causing test
failures on macOS. Use a -- to explicitly treat the input file as a path
and fix the test.
This effectively reverts r326168 and adds an alternative fix.
George Karpenkov [Mon, 26 Feb 2018 22:14:18 +0000 (22:14 +0000)]
[analyzer] Exploration strategy prioritizing unexplored nodes first
See D42775 for discussion. Turns out, just exploring nodes which
weren't explored first is not quite enough, as e.g. the first quick
traversal resulting in a report can mark everything as "visited", and
then subsequent traversals of the same region will get all the pitfalls
of DFS.
Priority queue-based approach in comparison shows much greater
increase in coverage and even performance, without sacrificing memory.
George Karpenkov [Mon, 26 Feb 2018 22:14:16 +0000 (22:14 +0000)]
[analyzer] Do not analyze bison-generated files
Bison/YACC generated files result in a very large number of (presumably)
false positives from the analyzer.
These false positives are "true" in a sense of the information analyzer
sees: assuming that the lexer can return any token at any point a number
of uninitialized reads does occur.
(naturally, the analyzer can not capture a complex invariant that
certain tokens can only occur under certain conditions).
Current fix simply stops analysis on those files.
I have examined a very large number of such auto-generated files, and
they do all start with such a comment.
Conversely, user code is very unlikely to contain such a comment.
A proper fix would be much harder, and would involve changing the
appropriate code in ExprEngine to be aware of the size limitations of
the type used for addressing.
This is failing on ASAN bots because asan expects column info,
and it's also failing on some linux bots for unknown reasons which
i need to investigate.
projects / clang / log