It seems this somehow made -Wempty-body fire in some macro cases where
it didn't before, e.g.
../../third_party/ffmpeg/libavcodec/bitstream.c(169,5): error: if statement has empty body [-Werror,-Wempty-body]
ff_dlog(NULL, "new table index=%d size=%d\n", table_index, table_size);
^
../../third_party/ffmpeg\libavutil/internal.h(276,80): note: expanded from macro 'ff_dlog'
# define ff_dlog(ctx, ...) do { if (0) av_log(ctx, AV_LOG_DEBUG, __VA_ARGS__); } while (0)
^
../../third_party/ffmpeg/libavcodec/bitstream.c(169,5): note: put the
semicolon on a separate line to silence this warning
Reverting until this can be figured out.
> Do not show it when `if` or `else` come from macros.
> E.g.,
>
> #define USED(A) if (A); else
> #define SOME_IF(A) if (A)
>
> void test() {
> // No warnings are shown in those cases now.
> USED(0);
> SOME_IF(0);
> }
>
> Patch by Ilya Biryukov!
>
> Differential Revision: https://reviews.llvm.org/D40185
llvm-svn: 318665
Do not show it when `if` or `else` come from macros.
E.g.,
#define USED(A) if (A); else
#define SOME_IF(A) if (A)
void test() {
// No warnings are shown in those cases now.
USED(0);
SOME_IF(0);
}
Patch by Ilya Biryukov!
Differential Revision: https://reviews.llvm.org/D40185
llvm-svn: 318556
Treat typedef enum as named enums instead of anonymous enums. Anonymous enums
are ignored by the warning, so previously, typedef enums were ignored as well.
llvm-svn: 312842
Summary:
Currently we build the co_await expressions on the wrong implicit statements of the implicit ranged for; Specifically we build the co_await expression wrapping the range declaration, but it should wrap the begin expression.
This patch fixes co_await on range for.
Reviewers: rsmith, GorNishanov
Reviewed By: GorNishanov
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D34021
llvm-svn: 305363
Summary:
If the first parameter of the function is the ImplicitParamDecl, codegen
automatically marks it as an implicit argument with `this` or `self`
pointer. Added internal kind of the ImplicitParamDecl to separate
'this', 'self', 'vtt' and other implicit parameters from other kind of
parameters.
Reviewers: rjmccall, aaron.ballman
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D33735
llvm-svn: 305075
The warning for unchanged loop variables outputted a diagnostic that was
dependent on iteration order from a pointer set, which is not always
deterministic. Switch to a set vector, which allows fast querying and
preserves ordering.
Also make other minor changes in this area.
Use more range-based for-loops.
Remove limitation on SourceRanges that no logner exists.
llvm-svn: 304519
https://bugs.llvm.org/show_bug.cgi?id=32933
Turns out clang wasn't really handling vla's (*) in C++11's for-range entirely correctly.
For e.g. This would lead to generation of buggy IR:
void foo(int b) {
int vla[b];
b = -1; // This store would affect the '__end = vla + b'
for (int &c : vla)
c = 0;
}
Additionally, code-gen would get confused when VLA's were reference-captured by lambdas, and then used in a for-range, which would result in an attempt to generate IR for '__end = vla + b' within the lambda's body - without any capture of 'b' - hence the assertion.
This patch modifies clang, so that for VLA's it translates the end pointer approximately into:
__end = __begin + sizeof(vla)/sizeof(vla->getElementType())
As opposed to the __end = __begin + b;
I considered passing a magic value into codegen - or having codegen special case the '__end' variable when it referred to a variably-modified type, but I decided against that approach, because it smelled like I would be increasing a complicated form of coupling, that I think would be even harder to maintain than the above approach (which can easily be optimized (-O1) to refer to the run-time bound that was calculated upon array's creation or copied into the lambda's closure object).
(*) why oh why gcc would you enable this by default?! ;)
llvm-svn: 303026
- also replace direct equality checks against the ConstantEvaluated enumerator with isConstantEvaluted(), in anticipation of adding finer granularity to the various ConstantEvaluated contexts and reinstating certain restrictions on where lambda expressions can occur in C++17.
- update the clang tablegen backend that uses these Enumerators, and add the relevant scope where needed.
llvm-svn: 299316
for unused values.
This fixes a regression caused by r298676, where constructor calls to
classes with non-trivial dtor were marked as unused if the first
argument is an initializer list. This is inconsistent (as the test
shows) and also warns on a reasonbly common code pattern where people
just call constructors to create and immediately destroy an object.
llvm-svn: 298853
This commit adds support for a new attribute that will be used to
distinguish between extensible and inextensible enums. There are three
main purposes of this attribute:
1. Give better control over when enum-related warnings are issued.
For example, in the code below, clang will not issue a -Wassign-enum
warning if the enum is marked "open":
enum __attribute__((enum_extensibility(closed))) EnumClosed {
B0 = 1, B1 = 10
};
enum __attribute__((enum_extensibility(open))) EnumOpen {
C0 = 1, C1 = 10
};
enum EnumClosed ec = 100; // warning issued
enum EnumOpen eo = 100; // no warning
2. Enable code-completion and debugging tools to offer better
suggestions.
3. Make it easier for swift's clang importer to determine which swift
type an enum should be mapped to.
For more details, see the discussion I started on cfe-dev:
http://lists.llvm.org/pipermail/cfe-dev/2017-February/052748.html
rdar://problem/12764379
rdar://problem/23145650
Differential Revision: https://reviews.llvm.org/D30766
llvm-svn: 298332
instantiation.
In preparation for converting the template stack to a more general context
stack (so we can include context notes for other kinds of context).
llvm-svn: 295686
r274291 made changes to prefer calling a move constructor to calling a
copy constructor when returning from a function. This caused programs to
crash when a __block variable in the heap was moved out and used later.
This commit fixes the bug by disallowing moving out of __block variables
implicitly.
rdar://problem/28181080
Differential Revision: https://reviews.llvm.org/D29908
llvm-svn: 295150
This flag serves no purpose other than to prevent us walking through a type to
check whether it contains an 'auto' specifier; this duplication of information
is error-prone, does not appear to provide any performance benefit, and will
become less practical once we support C++1z deduced class template types and
eventually constrained types from the Concepts TS.
No functionality change intended.
llvm-svn: 291737
This commit ensures that the switch warning "case value not in enumerated type"
isn't shown for opaque enums. We don't know the actual list of values in opaque
enums, so that warning is incorrect.
rdar://29230764
Differential Revision: https://reviews.llvm.org/D27299
llvm-svn: 289055
Summary:
Together these let you easily create diagnostics that
- are never emitted for host code
- are always emitted for __device__ and __global__ functions, and
- are emitted for __host__ __device__ functions iff these functions are
codegen'ed.
At the moment there are only three diagnostics that need this treatment,
but I have more to add, and it's not sustainable to write code for emitting
every such diagnostic twice, and from a special wrapper in SemaCUDA.cpp.
While we're at it, don't emit the function name in
err_cuda_device_exceptions: It's not necessary to print it, and making
this work in the new framework in the face of a null value for
dyn_cast<FunctionDecl>(CurContext) isn't worth the effort.
Reviewers: rnk
Subscribers: cfe-commits, tra
Differential Revision: https://reviews.llvm.org/D25139
llvm-svn: 284143
CheckSingleAssignmentConstraints. These no longer produce ExprError() when they
have not emitted an error, and reliably inform the caller when they *have*
emitted an error.
This fixes some serious issues where we would fail to emit any diagnostic for
invalid code and then attempt to emit code for an invalid AST, and conversely
some issues where we would emit two diagnostics for the same problem.
llvm-svn: 283508
This commit adds a traversal of the AST after Sema of a function that diagnoses
unguarded references to declarations that are partially available (based on
availability attributes). This traversal is only done when we would otherwise
emit -Wpartial-availability.
This commit is part of a feature I proposed here:
http://lists.llvm.org/pipermail/cfe-dev/2016-July/049851.html
Differential revision: https://reviews.llvm.org/D23003
llvm-svn: 278826
No semantic analysis yet.
This is a pain to disambiguate correctly, because the parsing rules for the
declaration form of a condition and of an init-statement are quite different --
for a token sequence that looks like a declaration, we frequently need to
disambiguate all the way to the ')' or ';'.
We could do better here in some cases by stopping disambiguation once we've
decided whether we've got an expression or not (rather than keeping going until
we know whether it's an init-statement declaration or a condition declaration),
by unifying our parsing code for the two types of declaration and moving the
syntactic checks into Sema; if this has a measurable impact on parsing
performance, I'll look into that.
llvm-svn: 274169
-Wfor-loop-analysis warnings for a for-loop with a condition variable. In such
a case, the loop condition variable is modified on each iteration of the loop
by definition.
Original commit message:
Rearrange condition handling so that semantic checks on a condition variable
are performed before the other substatements of the construct are parsed,
rather than deferring them until the end. This allows better error recovery
from semantic errors in the condition, improves diagnostic order, and is a
prerequisite for C++17 constexpr if.
llvm-svn: 273600
are performed before the other substatements of the construct are parsed,
rather than deferring them until the end. This allows better error recovery
from semantic errors in the condition, improves diagnostic order, and is a
prerequisite for C++17 constexpr if.
llvm-svn: 273548
classes.
MSVC actively uses unqualified lookup in dependent bases, lookup at the
instantiation point (non-dependent names may be resolved on things
declared later) etc. and all this stuff is the main cause of
incompatibility between clang and MSVC.
Clang tries to emulate MSVC behavior but it may fail in many cases.
clang could store lexed tokens for member functions definitions within
ClassTemplateDecl for later parsing during template instantiation.
It will allow resolving many possible issues with lookup in dependent
base classes and removing many already existing MSVC-specific
hacks/workarounds from the clang code.
llvm-svn: 272774
These ExprWithCleanups are added for holding a RunCleanupsScope not
for destructor calls; rather, they are for lifetime marks. This requires
ExprWithCleanups to keep a bit to indicate whether it have cleanups with
side effects (e.g. dtor calls).
Differential Revision: http://reviews.llvm.org/D20498
llvm-svn: 272296
For better performance and to unify code with offloading part we pass
scalar firstprivate values by value, instead of by reference. It will
remove some extra copying operations.
llvm-svn: 269751
Summary:
For PseudoObjectExpr, the DeclMatcher need to search only all the semantics
but also need to search pass OpaqueValueExpr for all potential uses for the
Decl.
Reviewers: thakis, rtrieu, rjmccall, doug.gregor
Subscribers: xazax.hun, rjmccall, doug.gregor, cfe-commits
Differential Revision: http://reviews.llvm.org/D17627
llvm-svn: 263087
-Wcomma will detect and warn on most uses of the builtin comma operator. It
currently whitelists the first and third statements of the for-loop. For other
cases, the warning can be silenced by casting the first operand of the comma
operator to void.
Differential Revision: http://reviews.llvm.org/D3976
llvm-svn: 261278
If the typo happens after a successful deduction for an earlier
return statement, we should check if the deduced type is null
before using it.
The typo correction happens after we try to deduce the return
type and we ignore the deduction from the typo and continue
to typo correction.
rdar://24342247
llvm-svn: 259820
is complete (with an error produced if not) and a function that merely queries
whether the type is complete. Either way we'll trigger instantiation if
necessary, but only the former will diagnose and recover from missing module
imports.
The intent of this change is to prevent a class of bugs where code would call
RequireCompleteType(..., 0) and then ignore the result. With modules, we must
check the return value and use it to determine whether the definition of the
type is visible.
This also fixes a debug info quality issue: calls to isCompleteType do not
trigger the emission of debug information for a type in limited-debug-info
mode. This allows us to avoid emitting debug information for type definitions
in more cases where we believe it is safe to do so.
llvm-svn: 256049
Summary:
This patch implements the 4.5 specification for the implicit data maps. OpenMP 4.5 specification changes the default way data is captured into a target region. All the non-aggregate kinds are passed by value by default. This required activating the capturing by value during SEMA for the target region. All the non-aggregate values that can be encoded in the size of a pointer are properly casted and forwarded to the runtime library. On top of fixing the previous weird behavior for mapping pointers in nested data regions (an explicit map was always required), this also improves performance as the number of allocations/transactions to the device per non-aggregate map are reduced from two to only one - instead of passing a reference and the value, only the value passed.
Explicit maps will be added later on once firstprivate, private, and map clauses' SEMA and parsing are available.
Reviewers: hfinkel, rjmccall, ABataev
Subscribers: cfe-commits, carlo.bertolli
Differential Revision: http://reviews.llvm.org/D14940
llvm-svn: 254521
1. Make the warning more strict in C mode. r172696 added code to suppress
warnings from macro expansions in system headers, which checks
`SourceMgr.isMacroBodyExpansion(E->IgnoreParens()->getExprLoc())`. Consider
this snippet:
#define FOO(x) (x)
void f(int a) {
FOO(a);
}
In C, the line `FOO(a)` is an `ImplicitCastExpr(ParenExpr(DeclRefExpr))`,
while it's just a `ParenExpr(DeclRefExpr)` in C++. So in C++,
`E->IgnoreParens()` returns the `DeclRefExpr` and the check tests the
SourceLoc of `a`. In C, the `ImplicitCastExpr` has the effect of checking the
SourceLoc of `FOO`, which is a macro body expansion, which causes the
diagnostic to be skipped. It looks unintentional that clang does different
things for C and C++ here, so use `IgnoreParenImpCasts` instead of
`IgnoreParens` here. This has the effect of the warning firing more often
than previously in C code – it now fires as often as it fires in C++ code.
2. Suppress the warning if it would warn on `UNREFERENCED_PARAMETER`.
`UNREFERENCED_PARAMETER` is a commonly used macro on Windows and it happens
to uselessly trigger -Wunused-value. As discussed in the thread
"rfc: winnt.h's UNREFERENCED_PARAMETER() vs clang's -Wunused-value" on
cfe-dev, fix this by special-casing this specific macro. (This costs a string
comparison and some fast-path lexing per warning, but the warning is emitted
rarely. It fires once in Windows.h itself, so this code runs at least once
per TU including Windows.h, but it doesn't run hundreds of times.)
http://reviews.llvm.org/D13969
llvm-svn: 251441
Objective-C ARC lifetime qualifiers are dropped when canonicalizing
function types. Perform the same adjustment before comparing the
deduced result types of lambdas. Fixes rdar://problem/22344904.
llvm-svn: 249065
This lets us pass functors (and lambdas) without void * tricks. On the
downside we can't pass CXXRecordDecl's Find* members (which are now type
safe) to lookupInBases directly, but a lambda trampoline is a small
price to pay. No functionality change intended.
llvm-svn: 243217
Move the diagnostic back to codegen so that we can compile ATL on the
self-host bot. We don't actually end up emitting code for the __try, so
the diagnostic won't be hit.
llvm-svn: 241761
This reverts commit r241244, but restricts SEH support to Win64.
This way, Chromium builds will still fall back on TUs with SEH, and
Clang developers can work on this incrementally upstream while patching
this small predicate locally. It'll also make it easier to review small
fixes.
llvm-svn: 241533
This re-lands r236052 and adds support for __exception_code().
In 32-bit SEH, the exception code is not available in eax. It is only
available in the filter function, and now we arrange to load it and
store it into an escaped variable in the parent frame.
As a consequence, we have to disable the "catch i8* null" optimization
on 32-bit and always generate a filter function. We can re-enable the
optimization if we detect an __except block that doesn't use the
exception code, but this probably isn't worth optimizing.
Reviewers: majnemer
Differential Revision: http://reviews.llvm.org/D10852
llvm-svn: 241171
This patch implements the functionality specified by DR948.
The changes are two fold. First, the parser was modified
to allow 'constexpr's to appear in condition declarations
(which was a hard error before). Second, Sema was modified
to cleanup maybe odr-used declarations by way of a call to
'ActOnFinishFullExpr'. As 'constexpr's were not allowed in
condition declarations before the cleanup wasn't necessary
(such declarations were always odr-used).
This fixes PR22491.
Differential Revision: http://reviews.llvm.org/D8978
llvm-svn: 240707
The patch is generated using this command:
$ tools/extra/clang-tidy/tool/run-clang-tidy.py -fix \
-checks=-*,llvm-namespace-comment -header-filter='llvm/.*|clang/.*' \
work/llvm/tools/clang
To reduce churn, not touching namespaces spanning less than 10 lines.
llvm-svn: 240270
This is just the clang-side of 32-bit SEH. LLVM still needs work, and it
will determinstically fail to compile until it's feature complete.
On x86, all outlined handlers have no parameters, but they do implicitly
take the EBP value passed in and use it to address locals of the parent
frame. We model this with llvm.frameaddress(1).
This works (mostly), but __finally block inlining can break it. For now,
we apply the 'noinline' attribute. If we really want to inline __finally
blocks on 32-bit x86, we should teach the inliner how to untangle
frameescape and framerecover.
Promote the error diagnostic from codegen to sema. It now rejects SEH on
non-Windows platforms. LLVM doesn't implement SEH on non-x86 Windows
platforms, but there's nothing preventing it.
llvm-svn: 236052
-Wrange-loop-analysis is a subgroup of -Wloop-analysis and will warn when
a range-based for-loop makes copies of the elements in the range. If possible,
suggest the proper type to prevent copies, or the non-reference to help
distinguish copy versus non-copy forms. Existing warnings in -Wloop-analysis
are moved to -Wfor-loop-analysis, also a subgroup of -Wloop-analysis.
Differential Revision: http://reviews.llvm.org/D4169
llvm-svn: 234804
The previous implementation would copy the attribute from the class to
functions that have the class as their return type when the functions
are first declared. This proved to have two flaws:
1) if the class is forward-declared without the attribute and a
function or method with the class as a its return type is declared,
and afterward the class is defined with warn_unused_result, the
function or method would never inherit the attribute, and
2) the check simply failed for functions and methods that are part of
a template instantiation, regardless of whether the class with
warn_unused_result is part of a specific instantiation or part of
the template itself (presumably because those function/method
declaration does not hit the same code path as a non-template one
and so never inherits the attribute).
The new approach is to instead modify the two places where a function or
method call is checked for the warn_unused_result attribute on the decl
by extending the checks to also look for the attribute on the decl's
return type.
Additionally, the check for return types that have the warn_unused_result
now excludes pointers and references to such types, as such return types do
not necessarily imply a transfer of ownership for the underlying object
being referred to by the return value. This does not change the behavior
of functions that are directly given the warn_unused_result attribute.
llvm-svn: 234526
Now that SmallString is a first-class citizen, most SmallString::str()
calls are not required. This patch removes a whole bunch of them, yet
there are lots more.
There are two use cases where str() is really needed:
1) To use one of StringRef member functions which is not available in
SmallString.
2) To convert to std::string, as StringRef implicitly converts while
SmallString do not. We may wish to change this, but it may introduce
ambiguity.
llvm-svn: 232622
ParseCompoundStatement() currently never returns StmtError, but if it did,
Sema would keep the __finally scope on its stack indefinitely. Explicitly
add an error callback that clears it.
llvm-svn: 231625
Since continue, break, return are much more common than __finally, this tries
to keep the work for continue, break, return O(1). Sema keeps a stack of active
__finally scopes (to do this, ActOnSEHFinally() is split into
ActOnStartSEHFinally() and ActOnFinishSEHFinally()), and the various jump
statements then check if the current __finally scope (if present) is deeper
than then destination scope of the jump.
The same warning for goto statements is still missing.
This is the moral equivalent of MSVC's C4532.
llvm-svn: 231623
After r228258, Clang started emitting C++ EH IR that LLVM wasn't ready
to deal with, even when exceptions were disabled with /EHs-. This time,
make /EHs- turn off -fexceptions while still emitting exceptional
constructs in functions using __try. Since Sema rejects C++ exception
handling constructs before CodeGen, landingpads should only appear in
such functions as the result of a __try.
llvm-svn: 228329
It caused a chromium base unittest that tests throwing and catching SEH
exceptions to fail (http://crbug.com/455488) and I suspect it might also
be the cause of the chromium clang win 64-bit shared release builder timing
out during compiles. So revert to see if that's true.
llvm-svn: 228262
There are four major kinds of declarations that cause code generation:
- FunctionDecl (includes CXXMethodDecl etc)
- ObjCMethodDecl
- BlockDecl
- CapturedDecl
This patch tracks __try usage on FunctionDecls and diagnoses __try usage
in other decls. If someone wants to use __try from ObjC, they can use it
from a free function, since the ObjC code will need an ObjC-style EH
personality.
Eventually we will want to look through CapturedDecls and track SEH
usage on the parent FunctionDecl, if present.
llvm-svn: 228058
This check does not apply when Borland extensions are enabled, as they
have a checked in test case indicating that mixed usage of SEH and C++
is supported.
llvm-svn: 227876
Hans Wennborg