When performing a type deduction from the return type, the FunctionDecl may be
attributed with a calling convention. In such a case, the retrieved type
location may be an AttributedTypeLoc. Performing a castAs<FunctionProtoTypeLoc>
on such a type loc would result in an assertion as they are not derived types.
Ensure that we correctly handle the attributed type location by looking through
it to the modified type loc.
Fixes an assertion triggered in C++14 mode.
llvm-svn: 219851
Summary:
This fixes PR20023. In order to implement this scoping rule, we piggy
back on the existing LabelDecl machinery, by creating LabelDecl's that
will carry the "internal" name of the inline assembly label, which we
will rewrite the asm label to.
Reviewers: rnk
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D4589
llvm-svn: 218230
The warning warns on TypedefNameDecls -- typedefs and C++11 using aliases --
that are !isReferenced(). Since the isReferenced() bit on TypedefNameDecls
wasn't used for anything before this warning it wasn't always set correctly,
so this patch also adds a few missing MarkAnyDeclReferenced() calls in
various places for TypedefNameDecls.
This is made a bit complicated due to local typedefs possibly being used only
after their local scope has closed. Consider:
template <class T>
void template_fun(T t) {
typename T::Foo s3foo; // YYY
(void)s3foo;
}
void template_fun_user() {
struct Local {
typedef int Foo; // XXX
} p;
template_fun(p);
}
Here the typedef in XXX is only used at end-of-translation unit, when YYY in
template_fun() gets instantiated. To handle this, typedefs that are unused when
their scope exits are added to a set of potentially unused typedefs, and that
set gets checked at end-of-TU. Typedefs that are still unused at that point then
get warned on. There's also serialization code for this set, so that the
warning works with precompiled headers and modules. For modules, the warning
is emitted when the module is built, for precompiled headers each time the
header gets used.
Finally, consider a function using C++14 auto return types to return a local
type defined in a header:
auto f() {
struct S { typedef int a; };
return S();
}
Here, the typedef escapes its local scope and could be used by only some
translation units including the header. To not warn on this, add a
RecursiveASTVisitor that marks all delcs on local types returned from auto
functions as referenced. (Except if it's a function with internal linkage, or
the decls are private and the local type has no friends -- in these cases, it
_is_ safe to warn.)
Several of the included testcases (most of the interesting ones) were provided
by Richard Smith.
(gcc's spelling -Wunused-local-typedefs is supported as an alias for this
warning.)
llvm-svn: 217298
Changes diagnostic options, language standard options, diagnostic identifiers, diagnostic wording to use c++14 instead of c++1y. It also modifies related test cases to use the updated diagnostic wording.
llvm-svn: 215982
Assigns indices to try blocks. These indices will used in constructing
tables that the mscrt function __except_handler3 reads during SEH.
Testing will occur once we actually emit the tables, in a subsequent
patch.
llvm-svn: 213437
is unused (this is match behavior when property-dot syntax is used to
use same getter). rdar://17514245
Patch by Anders Carlsson with minor refactoring by me.
llvm-svn: 213423
Give scope a SEHTryScope bit, set that in ParseSEHTry(), and let Sema
walk the scope chain to find the SEHTry parent on __leave statements.
(They are rare enough that it seems better to do the walk instead of
giving Scope a SEHTryParent pointer -- this is similar to AtCatchScope.)
llvm-svn: 212422
The compilation pipeline doesn't actually need to know about the high-level
concept of diagnostic mappings, and hiding the final computed level presents
several simplifications and other potential benefits.
The only exceptions are opportunistic checks to see whether expensive code
paths can be avoided for diagnostics that are guaranteed to be ignored at a
certain SourceLocation.
This commit formalizes that invariant by introducing and using
DiagnosticsEngine::isIgnored() in place of individual level checks throughout
lex, parse and sema.
llvm-svn: 211005
This patch implements semantic analysis to make sure that the loop is in OpenMP canonical form.
This is the form required for 'omp simd', 'omp for' and other loop pragmas.
Differential revision: http://reviews.llvm.org/D3778
llvm-svn: 210095
A return type is the declared or deduced part of the function type specified in
the declaration.
A result type is the (potentially adjusted) type of the value of an expression
that calls the function.
Rule of thumb:
* Declarations have return types and parameters.
* Expressions have result types and arguments.
llvm-svn: 200082
Due to statement expressions supported as GCC extension, it is possible
to put 'break' or 'continue' into a loop/switch statement but outside
its body, for example:
for ( ; ({ if (first) { first = 0; continue; } 0; }); )
This code is rejected by GCC if compiled in C mode but is accepted in C++
code. GCC bug 44715 tracks this discrepancy. Clang used code generation
that differs from GCC in both modes: only statement of the third
expression of 'for' behaves as if it was inside loop body.
This change makes code generation more close to GCC, considering 'break'
or 'continue' statement in condition and increment expressions of a
loop as it was inside the loop body. It also adds error for the cases
when 'break'/'continue' appear outside loop due to this syntax. If
code generation differ from GCC, warning is issued.
Differential Revision: http://llvm-reviews.chandlerc.com/D2518
llvm-svn: 199897
This involved making CheckReturnStackAddr into a static function, which
is now called by a top-level return value checking routine called
CheckReturnValExpr.
llvm-svn: 199790
pointer, since this invokes undefined behavior. Based on a patch by Artyom
Skrobov! Handling of dependent exception specifications and some additional
testcases by me.
llvm-svn: 199452
This commit changes -Wassign-enum to compare unqualified types. One could
think that this does not matter much, because who wants a value of enum type
that is const-qualified? But this breaks the intended pattern to silence this
warning with an explicit cast:
static const enum Foo z = (enum Foo) 42;
In this case, source type is 'enum Foo', and destination type is 'const enum
Foo', and if we compare qualified types, they don't match, so we used warn.
llvm-svn: 196548
the following pattern.
If 'case' expression refers to a static const variable of the correct enum
type, then we count this as a sufficient declaration of intent by the user,
so we silence the warning.
llvm-svn: 196546
function parameter that has array type. Such a parameter will be treated as
a pointer type instead, resulting in a missing begin function error is a
suggestion to dereference the pointer. This provides a different,
more informative diagnostic as well as point to the parameter declaration.
llvm-svn: 192512
When an AST file is built based on another AST file, it can use a decl from
the fist file, and therefore mark the "isUsed" bit. We need to note this in
the AST file so that the bit is set correctly when the second AST file is
loaded.
This patch introduces the distinction between setIsUsed() and markUsed() so
that we don't call into the ASTMutationListener callback when it wouldn't
be appropriate.
Fixes PR16635.
llvm-svn: 190016
- Some documenation were added.
- Usages of OpaquePtr<A>.getAsVal<A>() were replaced by OpaquePtr<A>.get().
- Methods getAs and getAsVal were renamed to getPtrTo and getPtrAs respectively.
llvm-svn: 189346
Specifically, the following features are not included in this commit:
- any sort of capturing within generic lambdas
- nested lambdas
- conversion operator for captureless lambdas
- ensuring all visitors are generic lambda aware
As an example of what compiles:
template <class F1, class F2>
struct overload : F1, F2 {
using F1::operator();
using F2::operator();
overload(F1 f1, F2 f2) : F1(f1), F2(f2) { }
};
auto Recursive = [](auto Self, auto h, auto ... rest) {
return 1 + Self(Self, rest...);
};
auto Base = [](auto Self, auto h) {
return 1;
};
overload<decltype(Base), decltype(Recursive)> O(Base, Recursive);
int num_params = O(O, 5, 3, "abc", 3.14, 'a');
Please see attached tests for more examples.
Some implementation notes:
- Add a new Declarator context => LambdaExprParameterContext to
clang::Declarator to allow the use of 'auto' in declaring generic
lambda parameters
- Augment AutoType's constructor (similar to how variadic
template-type-parameters ala TemplateTypeParmDecl are implemented) to
accept an IsParameterPack to encode a generic lambda parameter pack.
- Add various helpers to CXXRecordDecl to facilitate identifying
and querying a closure class
- LambdaScopeInfo (which maintains the current lambda's Sema state)
was augmented to house the current depth of the template being
parsed (id est the Parser calls Sema::RecordParsingTemplateParameterDepth)
so that Sema::ActOnLambdaAutoParameter may use it to create the
appropriate list of corresponding TemplateTypeParmDecl for each
auto parameter identified within the generic lambda (also stored
within the current LambdaScopeInfo). Additionally,
a TemplateParameterList data-member was added to hold the invented
TemplateParameterList AST node which will be much more useful
once we teach TreeTransform how to transform generic lambdas.
- SemaLambda.h was added to hold some common lambda utility
functions (this file is likely to grow ...)
- Teach Sema::ActOnStartOfFunctionDef to check whether it
is being called to instantiate a generic lambda's call
operator, and if so, push an appropriately prepared
LambdaScopeInfo object on the stack.
- Teach Sema::ActOnStartOfLambdaDefinition to set the
return type of a lambda without a trailing return type
to 'auto' in C++1y mode, and teach the return type
deduction machinery in SemaStmt.cpp to process either
C++11 and C++14 lambda's correctly depending on the flag.
- various tests were added - but much more will be needed.
A greatful thanks to all reviewers including Eli Friedman,
James Dennett and the ever illuminating Richard Smith. And
yet I am certain that I have allowed unidentified bugs to creep in;
bugs, that I will do my best to slay, once identified!
Thanks!
llvm-svn: 188977
loop variable has a type containing 'auto', set the declaration to be invalid
(because we couldn't deduce its type) to prevent follow-on errors.
llvm-svn: 188853
referenced as a member of the current instantiation. In that case, deduce the
type of the function to a dependent type rather than exposing an undeduced auto
type to the rest of the current instantiation.
The standard doesn't really say that the type is dependent in this case; I'll
bring this up with CWG.
llvm-svn: 188410
common function. The C++1y contextual implicit conversion rules themselves are
not yet implemented, however.
This also fixes a subtle bug where template instantiation context notes were
dropped for diagnostics coming from conversions for integral constant
expressions -- we were implicitly slicing a SemaDiagnosticBuilder into a
DiagnosticBuilder when producing these diagnostics, and losing their context
notes in the process.
llvm-svn: 182406
a FieldDecl from it, and propagate both into the closure type and the
LambdaExpr.
You can't do much useful with them yet -- you can't use them within the body
of the lambda, because we don't have a representation for "the this of the
lambda, not the this of the enclosing context". We also don't have support or a
representation for a nested capture of an init-capture yet, which was intended
to work despite not being allowed by the current standard wording.
llvm-svn: 181985
Move the creation of CapturedStmt parameters out of CodeGen and into
Sema, making it easier to customize the outlined function. The
ImplicitParamDecls are stored in the CapturedDecl using an
ASTContext-allocated array.
Differential Revision: http://llvm-reviews.chandlerc.com/D722
llvm-svn: 181043
the actual parser and support arbitrary id-expressions.
We're actually basically set up to do arbitrary expressions here
if we wanted to.
Assembly operands permit things like A::x to be written regardless
of language mode, which forces us to embellish the evaluation
context logic somewhat. The logic here under template instantiation
is incorrect; we need to preserve the fact that an expression was
unevaluated. Of course, template instantiation in general is fishy
here because we have no way of delaying semantic analysis in the
MC parser. It's all just fishy.
I've also fixed the serialization of MS asm statements.
This commit depends on an LLVM commit.
llvm-svn: 180976
are now two distinct canonical 'AutoType's: one is the undeduced 'auto'
placeholder type, and the other is a deduced-but-dependent type. All
deduced-to-a-non-dependent-type cases are still non-canonical.
llvm-svn: 180789
Add a CapturedStmt.h similar to Lambda.h to reduce the typing required to get
to the CapturedRegionKind enum. This also allows codegen to access this enum
without including Sema/ScopeInfo.h.
Also removes some duplicated code for capturing 'this' between CapturedStmt and
Lambda.
Differential Revision: http://llvm-reviews.chandlerc.com/D712
llvm-svn: 180710
Still to do here:
- we have a collection of syntactic accepts-invalids to diagnose
- support non-PODs in VLAs, including dynamic initialization /
destruction
- runtime checks (and throw std::bad_array_length) for bad bound
- support VLA capture by reference in lambdas
- properly support VLAs in range-based for (don't recompute bound)
llvm-svn: 179962
Add CapturedDecl to be the DeclContext for CapturedStmt, and perform semantic
analysis. Currently captures all variables by reference.
TODO: templates
Author: Ben Langmuir <ben.langmuir@intel.com>
Differential Revision: http://llvm-reviews.chandlerc.com/D433
llvm-svn: 179618
http://lab.llvm.org:8011/builders/clang-x86_64-darwin10-gdb went back green
before it processed the reverted 178663, so it could not have been the culprit.
Revert "Revert 178663."
This reverts commit 4f8a3eb2ce5d4ba422483439e20c8cbb4d953a41.
llvm-svn: 178682
For variables and functions clang used to store two storage classes. The one
"as written" in the code and a patched one, which, for example, propagates
static to the following decls.
This apparently is from the days clang lacked linkage computation. It is now
redundant and this patch removes it.
llvm-svn: 178663
picking up cleanups from earlier in the statement. Also fix a
crash-on-invalid where a reference to an invalid decl from an
enclosing scope was causing an expression to fail to build, but
only *after* a cleanup was registered from that statement,
causing an assertion downstream.
The crash-on-valid is rdar://13459289.
llvm-svn: 177692
The TypeLoc hierarchy used the llvm::cast machinery to perform undefined
behavior by casting pointers/references to TypeLoc objects to derived types
and then using the derived copy constructors (or even returning pointers to
derived types that actually point to the original TypeLoc object).
Some context is in this thread:
http://lists.cs.uiuc.edu/pipermail/llvmdev/2012-December/056804.html
Though it's spread over a few months which can be hard to read in the mail
archive.
llvm-svn: 175462
This is inspired by a number of false positives in real code, including
PR14968. I've added test cases reduced from these false positives to
test/Sema/unused-expr.c, as well as corresponding test cases that pass the
offending expressions as arguments to a no-op macro to ensure that we do warn
there.
This also removes my previous tweak from r166522/r166534, so that we warn on
unused cast expressions in macro arguments.
There were several test cases that were using -Wunused-value to test general
diagnostic emission features; I changed those to use other warnings or warn on
a macro argument expression. I stared at the test case for PR14399 for a while
with Richard Smith and we believe the new test case exercises the same
codepaths as before.
llvm-svn: 172696
it apart from [[gnu::noreturn]] / __attribute__((noreturn)), since their
semantics are not equivalent (for instance, we treat [[gnu::noreturn]] as
affecting the function type, whereas [[noreturn]] does not).
llvm-svn: 172691
ActOnFinishFullExpr that some of its checks only apply to discarded-value
expressions. This adds missing checks for unexpanded variadic template
parameter packs to a handful of constructs.
llvm-svn: 172485
Previously, -Wunused-comparison ignored comparisons in both macro bodies and
macro arguments, but we would still emit a -Wunused-value warning for either.
Now we correctly emit -Wunused-comparison for expressions in macro arguments.
Also, add isMacroBodyExpansion to SourceManager, to go along with
isMacroArgExpansion.
llvm-svn: 172279
in case condition type. // rdar://11577384.
Test is conditionalized on x86_64-apple triple as
I am not sure if the INT_MAX/LONG_MAX values in the test
will pass this test for other hosts.
llvm-svn: 172016
uncovered.
This required manually correcting all of the incorrect main-module
headers I could find, and running the new llvm/utils/sort_includes.py
script over the files.
I also manually added quite a few missing headers that were uncovered by
shuffling the order or moving headers up to be main-module-headers.
llvm-svn: 169237
but can be dereferenced to form an expression which does have viable begin/end
functions, then typo-correct the range, even if something else goes wrong with
the statement (such as inaccessible begin/end or the wrong type of loop
variable).
In order to ensure we recover correctly and produce any followup diagnostics in
this case, redo semantic analysis on the for-range statement outside of the
diagnostic trap, after issuing the typo-correction.
llvm-svn: 164323
The old error message stating that 'begin' was an undeclared identifier
is replaced with a new message explaining that the error is in the range
expression, along with which of the begin() and end() functions was
problematic if relevant.
Additionally, if the range was a pointer type or defines operator*,
attempt to dereference the range, and offer a FixIt if the modified range
works.
llvm-svn: 162248
These require special handling, which we don't currently handle. This is being
put in place to ensure we don't do invalid symbol table lookups or try to parse
invalid assembly. The test cases just makes sure the latter isn't happening.
llvm-svn: 162050
variables, function or label references. The former is a potential clobber.
The latter is either an input or an output. Unfortunately, it's difficult to
test this patch at the moment, but the added test case will eventually do so.
llvm-svn: 162026
statement. For example,
if (x)
__asm out dx, ax __asm out dx, ax
results in a single inline asm statement (i.e., both "out dx, ax" statements are
predicated on if(x)).
llvm-svn: 161986
The AsmParser expects a single asm instruction, but valid ms-style inline asm
statements may contain multiple instructions.
This happens with asm blocks
__asm {
mov ebx, eax
mov ecx, ebx
}
or when multiple asm statements are adjacent to one another
__asm mov ebx, eax
__asm mov ecx, ebx
and
__asm mov ebx, eax __asm mov ecx, ebx
Currently, asm blocks are not properly handled.
llvm-svn: 161780
asm statements are those that don't reference variable names, function names,
and labels.
Add logic to generate a patched AsmString that will eventually be consumed by
the AsmParser. No functional change at this point, so unfortunately no test
case.
llvm-svn: 161508
Also, fix a subtle bug, which occurred due to lookupPrivateMethod
defined in DeclObjC.h not looking up the method inside parent's
categories.
Note, the code assumes that Class's parent object has the same methods
as what's in the Root class of a the hierarchy, which is a heuristic
that might not hold for hierarchies which do not descend from NSObject.
Would be great to fix this in the future.
llvm-svn: 160885
In C, enum constants have the type of the enum's underlying integer type,
rather than the type of the enum. (This is not true in C++.) Thus, when a
block's return type is inferred from an enum constant, it is incompatible
with expressions that return the enum type.
In r158899, I told block returns to pretend that enum constants have enum
type, like in C++. Doug Gregor pointed out that this can break existing code.
Now, we don't check the types of return statements until the end of the block.
This lets us go back and add implicit casts in blocks with mixed enum
constants and enum-typed expressions.
<rdar://problem/11662489> (again)
llvm-svn: 159591
In C, enum constants have the type of the enum's underlying integer type,
rather than the type of the enum. (This is not true in C++.) This leads to
odd warnings when returning enum constants directly in blocks with inferred
return types. The easiest way out of this is to pretend that, like C++, enum
constants have enum type when being returned from a block.
<rdar://problem/11662489>
llvm-svn: 158899
error was asserting on anything that included Windows.h. MS-style inline asm is
still dropped, but at least now we're not completely silent about it.
llvm-svn: 158833
In addition, I've made the pointer and reference typedef 'void' rather than T*
just so they can't get misused. I would've omitted them entirely but
std::distance likes them to be there even if it doesn't use them.
This rolls back r155808 and r155869.
Review by Doug Gregor incorporating feedback from Chandler Carruth.
llvm-svn: 158104
@throw expression; l2r conversion can introduce new cleanups
in certain cases, like when the expression is an ObjC property
reference of retainable type in ARC.
llvm-svn: 156425
Sema::ConvertToIntegralOrEnumerationType() from PartialDiagnostics to
abstract "diagnoser" classes. Not much of a win here, but we're
-several PartialDiagnostics.
llvm-svn: 156217
off PartialDiagnostic. PartialDiagnostic is rather heavyweight for
something that is in the critical path and is rarely used. So, switch
over to an abstract-class-based callback mechanism that delays most of
the work until a diagnostic is actually produced. Good for ~11k code
size reduction in the compiler and 1% speedup in -fsyntax-only on the
code in <rdar://problem/11004361>.
llvm-svn: 156176
filter_decl_iterator had a weird mismatch where both op* and op-> returned T*
making it difficult to generalize this filtering behavior into a reusable
library of any kind.
This change errs on the side of value, making op-> return T* and op* return
T&.
(reviewed by Richard Smith)
llvm-svn: 155808
attached. Since we do not support any attributes which appertain to a statement
(yet), testing of this is necessarily quite minimal.
Patch by Alexander Kornienko!
llvm-svn: 154723
NSNumber, and boolean literals. This includes both Sema and Codegen support.
Included is also support for new Objective-C container subscripting.
My apologies for the large patch. It was very difficult to break apart.
The patch introduces changes to the driver as well to cause clang to link
in additional runtime support when needed to support the new language features.
Docs are forthcoming to document the implementation and behavior of these features.
llvm-svn: 152137
* if, switch, range-based for: warn if semicolon is on the same line.
* for, while: warn if semicolon is on the same line and either next
statement is compound statement or next statement has more
indentation.
Replacing the semicolon with {} or moving the semicolon to the next
line will always silence the warning.
Tests from SemaCXX/if-empty-body.cpp merged into SemaCXX/warn-empty-body.cpp.
llvm-svn: 150515
value of class type, look for a unique conversion operator converting to
integral or unscoped enumeration type and use that. Implements [expr.const]p5.
Sema::VerifyIntegerConstantExpression now performs the conversion and returns
the converted result. Some important callers of Expr::isIntegralConstantExpr
have been switched over to using it (including all of those required for C++11
conformance); this switch brings a side-benefit of improved diagnostics and, in
several cases, simpler code. However, some language extensions and attributes
have not been moved across and will not perform implicit conversions on
constant expressions of literal class type where an ICE is required.
In passing, fix static_assert to perform a contextual conversion to bool on its
argument.
llvm-svn: 149776
array new expression. This lays some groundwork for the implicit conversion to
integral or unscoped enumeration which C++11 ICEs undergo.
llvm-svn: 149772
Fix some review comments.
Add a test for deduction when std::initializer_list isn't available yet.
Fix redundant error messages. This fixes and outstanding FIXME too.
llvm-svn: 148735
Clang previously implemented -Wswitch-enum the same as -Wswitch. This patch
corrects the behavior to match GCC's. The critical/only difference being that
-Wswitch-enum is not silenced by the presence of a default case in the switch.
llvm-svn: 148679
For consistency with GCC & reasonable sanity. The FIXME suggests that the
original author was perhaps using the default check for some other purpose,
not realizing the more obvious limitation/false-negatives it creates, but this
doesn't seem to produce any regressions & fixes the included test.
llvm-svn: 148649
This warning acts as the complement to the main -Wswitch-enum warning (which
warns whenever a switch over enum without a default doesn't cover all values of
the enum) & has been an an-doc coding convention in LLVM and Clang in my
experience. The purpose is to ensure there's never a "dead" default in a
switch-over-enum because this would hide future -Wswitch-enum errors.
The name warning has a separate flag name so it can be disabled but it's grouped
under -Wswitch-enum & is on-by-default because of this.
The existing violations of this rule in test cases have had the warning disabled
& I've added a specific test for the new behavior (many negative cases already
exist in the same test file - and none regressed - so I didn't add more).
Reviewed by Ted Kremenek ( http://lists.cs.uiuc.edu/pipermail/cfe-commits/Week-of-Mon-20120116/051690.html )
llvm-svn: 148640
values and non-type template arguments of integral and enumeration types.
This change causes some legal C++98 code to no longer compile in C++11 mode, by
enforcing the C++11 rule that narrowing integral conversions are not permitted
in the final implicit conversion sequence for the above cases.
llvm-svn: 148439
Objective-C classes. This has two purposes: to consistently provide
"forward declaration here" notes when we hit an incomplete type, and
to give LLDB a chance to complete the type.
RequireCompleteType bits from Sean Callanan!
llvm-svn: 144573
property references to use a new PseudoObjectExpr
expression which pairs a syntactic form of the expression
with a set of semantic expressions implementing it.
This should significantly reduce the complexity required
elsewhere in the compiler to deal with these kinds of
expressions (e.g. IR generation's special l-value kind,
the static analyzer's Message abstraction), at the lower
cost of specifically dealing with the odd AST structure
of these expressions. It should also greatly simplify
efforts to implement similar language features in the
future, most notably Managed C++'s properties and indexed
properties.
Most of the effort here is in dealing with the various
clients of the AST. I've gone ahead and simplified the
ObjC rewriter's use of properties; other clients, like
IR-gen and the static analyzer, have all the old
complexity *and* all the new complexity, at least
temporarily. Many thanks to Ted for writing and advising
on the necessary changes to the static analyzer.
I've xfailed a small diagnostics regression in the static
analyzer at Ted's request.
llvm-svn: 143867
implicitly perform an lvalue-to-rvalue conversion if used on an lvalue
expression. Also improve the documentation of Expr::Evaluate* to indicate which
of them will accept expressions with side-effects.
llvm-svn: 143263
rvalue. An assertion to catch this is in ImpCastExprToType will follow, but
vector operations currently trip over this (due to omitting the usual arithmetic
conversions). Also add an assert to catch missing lvalue-to-rvalue conversions
on the LHS of ->.
llvm-svn: 143155
expressions: expressions which refer to a logical rather
than a physical l-value, where the logical object is
actually accessed via custom getter/setter code.
A subsequent patch will generalize the AST for these
so that arbitrary "implementing" sub-expressions can
be provided.
Right now the only client is ObjC properties, but
this should be generalizable to similar language
features, e.g. Managed C++'s __property methods.
llvm-svn: 142914
statements. As noted in the documentation for the AST node, the
semantics of __if_exists/__if_not_exists are somewhat different from
the way Visual C++ implements them, because our parsed-template
representation can't accommodate VC++ semantics without serious
contortions. Hopefully this implementation is "good enough".
llvm-svn: 142901
- Remodel Expr::EvaluateAsInt to behave like the other EvaluateAs* functions,
and add Expr::EvaluateKnownConstInt to capture the current fold-or-assert
behaviour.
- Factor out evaluation of bitfield bit widths.
- Fix a few places which would evaluate an expression twice: once to determine
whether it is a constant expression, then again to get the value.
llvm-svn: 141561
builtin types (When requested). This is another step toward making
ASTUnit build the ASTContext as needed when loading an AST file,
rather than doing so after the fact. No actual functionality change (yet).
llvm-svn: 138985
-Wunused was a mistake. It resulted in duplicate warnings and lots of
other hacks. Instead, this should be a special sub-category to
-Wunused-value, much like -Wunused-result is.
Moved to -Wunused-comparison, moved the implementation to piggy back on
the -Wunused-value implementation instead of rolling its own, different
mechanism for catching all of the "interesting" statements.
I like the unused-value mechanism for this better, but its currently
missing several top-level statements. For now, I've FIXME-ed out those
test cases. I'll enhance the generic infrastructure to catch these
statements in a subsequent patch.
This patch also removes the cast-to-void fixit hint. This hint isn't
available on any of the other -Wunused-value diagnostics, and if we want
it to be, we should add it generically rather than in one specific case.
llvm-svn: 137822
code is very likely to be buggy, but its going to require more
significant changes on the part of the user to correct it in this case.
llvm-svn: 137820
a complement to the warnings we provide in condition expressions. Much
like we warn on conditions such as:
int x, y;
...
if (x = y) ... // Almost always a typo of '=='
This warning applies the complementary logic to "top-level" statements,
or statements whose value is not consumed or used in some way:
int x, y;
...
x == y; // Almost always a type for '='
We also mirror the '!=' vs. '|=' logic.
The warning is designed to fire even for overloaded operators for two reasons:
1) Especially in the presence of widespread templates that assume
operator== and operator!= perform the expected comparison operations,
it seems unreasonable to suppress warnings on the offchance that
a user has written a class that abuses these operators, embedding
side-effects or other magic within them.
2) There is a trivial source modification to silence the warning for
truly exceptional cases:
(void)(x == y); // No warning
A (greatly reduced) form of this warning has already caught a number of
bugs in our codebase, so there is precedent for it actually firing. That
said, its currently off by default, but enabled under -Wall.
There are several fixmes left here that I'm working on in follow-up
patches, including de-duplicating warnings from -Wunused, sharing code
with -Wunused's implementation (and creating a nice place to hook
diagnostics on "top-level" statements), and handling cases where a proxy
object with a bool conversion is returned, hiding the operation in the
cleanup AST nodes.
Suggestions for any of this code more than welcome. Also, I'd really
love suggestions for better naming than "top-level".
llvm-svn: 137819
ActOnStartOfSwitchStmt (i.e. before binding up a full-expression)
instead of ActOnFinishSwitchStmt.
Among other things, this means that property l-values are properly
converted inside the full-expression.
llvm-svn: 137014
for-in statements; specifically, make sure to close over any
temporaries or cleanups it might require. In ARC, this has
implications for the lifetime of the collection, so emit it
with a retain and release it upon exit from the loop.
rdar://problem/9817306
llvm-svn: 136204
throw-expressions, such that we don't consider the NRVO when the
non-volatile automatic object comes from outside the innermost try
scope (C++0x [class.copymove]p13). In C++98/03, our ASTs were
incorrect but it didn't matter because IR generation doesn't actually
apply the NRVO here. In C++0x, however, we were moving from an object
when in fact we should have copied from it. Fixes PR10142 /
<rdar://problem/9714312>.
llvm-svn: 134548
