MaterializeTemporaryExpr captures a reference binding to a temporary
value, making explicit that the temporary value (a prvalue) needs to
be materialized into memory so that its address can be used. The
intended AST invariant here is that a reference will always bind to a
glvalue, and MaterializeTemporaryExpr will be used to convert prvalues
into glvalues for that binding to happen. For example, given
const int& r = 1.0;
The initializer of "r" will be a MaterializeTemporaryExpr whose
subexpression is an implicit conversion from the double literal "1.0"
to an integer value.
IR generation benefits most from this new node, since it was
previously guessing (badly) when to materialize temporaries for the
purposes of reference binding. There are likely more refactoring and
cleanups we could perform there, but the introduction of
MaterializeTemporaryExpr fixes PR9565, a case where IR generation
would effectively bind a const reference directly to a bitfield in a
struct. Addresses <rdar://problem/9552231>.
llvm-svn: 133521
an assembly file it worked correctly, while for a .c file it would given an
error about how --noexecstack is not a supported argument to -Wa.
llvm-svn: 133489
(or follow up) extern declaration with weak_import as
an actual definition. make clang follows this behavior.
// rdar://9538608
llvm-gcc treats an extern declaration with weak_import
llvm-svn: 133450
types printed in various diagnostics.
We could omit checking for the types, but that can mask errors where the
wrong type is streamed into the diagnostic. There was at least one of
these caught by this test already.
llvm-svn: 133429
pointers I found while working on the NULL arithmetic warning. We here
always assuming the LHS was the pointer, instead of using the selected
pointer expression.
llvm-svn: 133428
effectively that this abstraction simply doesn't exist. That is
highlighted by the fact that by using it we were papering over a more
serious error in this warning: the fact that we warned for *invalid*
constructs involving member pointers and block pointers.
I've fixed the obvious issues with the warning here, but this is
confirming an original suspicion that this warning's implementation is
flawed. I'm looking into how we can implement this more reasonably. WIP
on that front.
llvm-svn: 133425
ConvertType on InitListExprs as they are being converted. This is
needed for a forthcoming patch, and improves the IR generated anyway
(see additional type names in testcases).
This patch also converts a bunch of std::vector's in CGObjCMac to use
C arrays. There are a ton more that should be converted as well.
llvm-svn: 133413
Trieu, and fix them by checking for array and function types as well as
pointer types.
I've added a predicate method on Type to bundle together the logic we're
using here: isPointerLikeType(). I'd welcome better names for this
predicate, this is the best I came up with. It's implemented as a switch
to be a touch lighter weight than all the chained isa<...> casts that
would result otherwise.
llvm-svn: 133383
deducing template parameter types. Recently Clang began enforcing the
more strict checking that the argument type and the deduced function
parameter type (after substitution) match, but that only consideres
qualification conversions.
One problem with this patch is that we check noreturn conversions and
qualification conversions independently. If a valid conversion would
require *both*, perhaps interleaved with each other, it will be
rejected. If this actually occurs (I'm not yet sure it does) and is in
fact a problem (I'm not yet sure it is), there is a FIXME to implement
more intelligent conversion checking.
However, this step at least allows Clang to resume accepting valid code
we're seeing in the wild.
llvm-svn: 133327
silently dropped ownership qualifiers that were being applied to
ownership-qualified, substituted type that was *not* a substituted
template type parameter. We now provide a diagnostic in such cases,
and recover by dropping the added qualifiers.
Document this behavior in the ARC specification.
llvm-svn: 133309
qualifiers, so that an __unsafe_unretained-qualified type T in ARC code
will have the same mangling as T in non-ARC code, improving ABI
interoperability. This works now because we infer or require a
lifetime qualifier everywhere one can appear in an external
interface. Another part of <rdar://problem/9595486>.
llvm-svn: 133306
ownership-unqualified retainable object type as __strong. This allows
us to write, e.g.,
std::vector<id>
and we'll infer that the vector's element types have __strong
ownership semantics, which is far nicer than requiring:
std::vector<__strong id>
Note that we allow one to override the ownership qualifier of a
substituted template type parameter, e.g., given
template<typename T>
struct X {
typedef __weak T type;
};
X<id> is treated the same as X<__strong id>. At instantiation type,
the __weak in "__weak T" overrides the (inferred or specified)
__strong on the template argument type, so that we can still provide
metaprogramming transformations.
This is part of <rdar://problem/9595486>.
llvm-svn: 133303
separate aggregate temporary and then memcpy it over to the
destination. This fixes a regression I introduced with r133235, where
the compound literal on the RHS of an assignment makes use of the
structure on the LHS of the assignment.
I'm deeply suspicious of AggExprEmitter::VisitBinAssign()'s
optimization where it emits the RHS of an aggregate assignment
directly into the LHS lvalue without checking whether there is any
aliasing between the LHS/RHS. However, I'm not in a position to
revisit this now.
Big thanks to Eli for finding the regression!
llvm-svn: 133261
they should still be officially __strong for the purposes of errors,
block capture, etc. Make a new bit on variables, isARCPseudoStrong(),
and set this for 'self' and these enumeration-loop variables. Change
the code that was looking for the old patterns to look for this bit,
and change IR generation to find this bit and treat the resulting
variable as __unsafe_unretained for the purposes of init/destroy in
the two places it can come up.
llvm-svn: 133243
storage specifier is different from the storage specifier on the
template. If that storage specifier is the same, then we only warn.
Thanks to John for the prodding.
llvm-svn: 133236
C++, which means:
- binding the temporary as needed in Sema, so that we generate the
appropriate call to the destructor, and
- emitting the compound literal into the appropriate location for
the aggregate, rather than trying to emit it as a temporary and
memcpy() it.
Fixes PR10138 / <rdar://problem/9615901>.
llvm-svn: 133235
__builtin_ versions of these functions as well as the normal function
versions, so that it works on platforms where memset/memcpy/memmove
are macros that map down to the builtins (e.g., Darwin). Fixes
<rdar://problem/9372688>.
llvm-svn: 133173
checks that the deduced argument type for a function call matches the
actual argument type provided. The only place we've found where the
consistency checking should actually cause template argument deduction
failure is due to qualifier differences that don't fall into the realm
of qualification conversions (which are *not* checked when we
initially perform deduction). However, we're performing the full
checking as specified in the standard to ensure that no other cases
exist.
Fixes PR9233 / <rdar://problem/9039590>.
llvm-svn: 133163
and the programmer intended to write 'sizeof(*p)'. There are several
elements to the new version:
1) The actual expressions are compared in order to more accurately flag
the case where the pattern that works for an array has been used, or
a '*' has been omitted.
2) Only do a loose type-based check for record types. This prevents us
from warning when we happen to be copying around chunks of data the
size of a pointer and the pointer types for the sizeof and
source/dest match.
3) Move all the diagnostics behind the runtime diagnostic filter. Not
sure this is really important for this particular diagnostic, but
almost everything else in SemaChecking.cpp does so.
4) Make the wording of the diagnostic more precise and informative. At
least to my eyes.
5) Provide highlighting for the two expressions which had the unexpected
similarity.
6) Place this diagnostic under a flag: -Wsizeof-pointer-memaccess
This uses the Stmt::Profile system for computing #1. Because of the
potential cost, this is guarded by the warning flag. I'd be interested
in feedback on how bad this is in practice; I would expect it to be
quite cheap in practice. Ideas for a cheaper / better way to do this are
also welcome.
The diagnostic wording could likely use some further wordsmithing.
Suggestions welcome here. The goals I had were to: clarify that its the
interaction of 'memset' and 'sizeof' and give more reasonable
suggestions for a resolution.
An open question is whether these diagnostics should have the note
attached for silencing by casting the dest/source pointer to void*.
llvm-svn: 133155
argument types for mem{set,cpy,move}. Character pointers, much like void
pointers, often point to generic "memory", so trying to check whether
they match the type of the argument to 'sizeof' (or other checks) is
unproductive and often results in false positives.
Nico, please review; does this miss any of the bugs you were trying to
find with this warning? The array test case you had should be caught by
the array-specific sizeof warning I think.
llvm-svn: 133136
pretty. In particular this makes it much easier for me to read messages
such as:
x.cc:42: ?: has lower ...
Where I'm inclined to associate the third ':' with a missing column
number, but in fact column numbers have been turned off. Similar
punctuation collisions happened elsewhere as well.
llvm-svn: 133121
Language-design credit goes to a lot of people, but I particularly want
to single out Blaine Garst and Patrick Beard for their contributions.
Compiler implementation credit goes to Argyrios, Doug, Fariborz, and myself,
in no particular order.
llvm-svn: 133103
were just punting on template argument deduction for a number of type
nodes. Most of them, obviously, didn't matter.
As a consequence of this, make extended vector types (via the
ext_vector_type attribute) actually work properly for several
important cases:
- If the attribute appears in a type-id (i.e, not attached to a
typedef), actually build a proper vector type
- Build ExtVectorType whenever the size is constant; previously, we
were building DependentSizedExtVectorType when the size was constant
but the type was dependent, which makes no sense at all.
- Teach template argument deduction to handle
ExtVectorType/DependentSizedExtVectorType.
llvm-svn: 133060
before the template parameters have acquired a proper context (e.g.,
because the enclosing context has yet to be built), provide empty
parameter lists for all outer template parameter scopes to inhibit any
substitution for those template parameters. Fixes PR9643 /
<rdar://problem/9251019>.
llvm-svn: 133055
- (bounded copies) Be more conservative about how much is being copied.
- (str(n)cat) If we can't compute the exact final length of an append operation, we can still lower-bound it.
- (stpcpy) Fix the conjured return value at the end to actually be returned.
This requires these supporting changes:
- C string metadata symbols are still live even when buried in a SymExpr.
- "Hypothetical" C string lengths, to represent a value that /will/ be passed to setCStringLength() if all goes well. (The idea is to allow for temporary constrainable symbols that may end up becoming permanent.)
- The 'checkAdditionOverflow' helper makes sure that the two strings being appended in a strcat don't overflow size_t. This should never *actually* happen; the real effect is to keep the final string length from "wrapping around" in the constraint manager.
This doesn't actually test the "bounded" operations (strncpy and strncat) because they can leave strings unterminated. Next on the list!
llvm-svn: 133046
Change the output for -Wshift-overflow and
-Wshift-sign-overflow to an unsigned hexadecimal. It makes
more sense for looking at bits than a signed decimal does.
Also, change the diagnostic's wording from "overrides"
to "sets".
This uses a new optional argument in APInt::toString()
that adds the '0x' prefix to hexademical numbers.
This fixes PR 9651.
Patch by nobled@dreamwidth.org!
llvm-svn: 133033
in a noexcept exception specification because it isn't part of the
canonical type. This ensures that we keep the exact expression written
in the noexcept exception specification, rather than accidentally
"adopting" a previously-written and canonically "equivalent" function
prototype. Fixes PR10087.
llvm-svn: 132998
as constant size arrays. This has slightly different semantics in some insane cases, but allows
us to accept some constructs that GCC does. Continue to be pedantic in -std=c99 and other
modes. This addressed rdar://8733881 - error "variable-sized object may not be initialized"; g++ accepts same code
llvm-svn: 132983
- Move a test from test/SemaTemplate/instantiate-expr-3.cpp, it did not belong there
- Incomplete and abstract types are considered hard errors
llvm-svn: 132979
This patch tries relatively hard to avoid creating an extra copy if it can be avoided (see test3 in the included testcase), but it is not possible to avoid in some cases (like test2 in the included testcase).
rdar://9483886
llvm-svn: 132957
- Move the diagnostic to the case statement instead of at the end of the switch
- Add a fix-it hint as to how to fix the compilation error
llvm-svn: 132903
struct {
typedef int A = 0;
};
According to the C++11 standard, this is not ill-formed, but does not have any ascribed meaning. We can't reasonably accept it, so treat it as ill-formed.
Also switch C++ from an incorrect 'fields can only be initialized in constructors' diagnostic for this case to C's 'illegal initializer (only variables can be initialized)'
llvm-svn: 132890
Related result types apply Cocoa conventions to the type of message
sends and property accesses to Objective-C methods that are known to
always return objects whose type is the same as the type of the
receiving class (or a subclass thereof), such as +alloc and
-init. This tightens up static type safety for Objective-C, so that we
now diagnose mistakes like this:
t.m:4:10: warning: incompatible pointer types initializing 'NSSet *'
with an
expression of type 'NSArray *' [-Wincompatible-pointer-types]
NSSet *array = [[NSArray alloc] init];
^ ~~~~~~~~~~~~~~~~~~~~~~
/System/Library/Frameworks/Foundation.framework/Headers/NSObject.h:72:1:
note:
instance method 'init' is assumed to return an instance of its
receiver
type ('NSArray *')
- (id)init;
^
It also means that we get decent type inference when writing code in
Objective-C++0x:
auto array = [[NSMutableArray alloc] initWithObjects:@"one", @"two",nil];
// ^ now infers NSMutableArray* rather than id
llvm-svn: 132868
Also, have Environment stop looking through NoOp casts; it didn't match the behavior of LiveVariables. And once that's gone, the whole cast block of that switch is unnecessary.
llvm-svn: 132840
- Removed fix-it hints from template instaniations since changes to the
templates are rarely helpful.
- Changed the caret in template instaniations from the class/struct name to the
class/struct keyword, matching the other warnings.
- Do not offer fix-it hints when multiple declarations disagree. Warnings are
still given.
- Once a definition is found, offer a fix-it hint to all previous declarations
with wrong tag.
- Declarations that disagree with a previous definition will get a fix-it hint
to change the declaration.
llvm-svn: 132831
This is a follow-up to r132565, and should address the rest of PR9969:
Warn about cases such as
int foo(A a, bool b) {
return a + b ? 1 : 2; // user probably meant a + (b ? 1 : 2);
}
also when + is an overloaded operator call.
llvm-svn: 132784
namespace set algorithm (re-)introduced. We may not have seen the 'std'
namespace, but we should still suggested associated namespaces. Easy
fix, but a bit annoying to test.
llvm-svn: 132744
specializations within an explicit instantiation to default to off
(enabled by -pedantic). Nobody else seem to implement C++
[temp.explicit]p3. Fixes PR10093.
llvm-svn: 132704
specializing a member of an unspecialized template, and recover from
such errors without crashing. Fixes PR10024 / <rdar://problem/9509761>.
llvm-svn: 132677
compared even when one is a reference binding and the other is not
(<rdar://problem/9173984>), but the definition of an identity sequence
does not involve lvalue-to-rvalue adjustments (PR9507). Fix both
inter-related issues.
llvm-svn: 132660
return <expression> ;
in blocks with a 'void' result type, so long as <expression> has type
'void'. This follows the rules for C++ functions.
llvm-svn: 132658
with a type-dependent expression, infer the placeholder type
'Context.DependentTy' to indicate that this is just a
placeholder. Fixes PR9982 / <rdar://problem/9486685>.
llvm-svn: 132657
__builtin_astype(): Used to reinterpreted as another data type of the same size using for both scalar and vector data types.
Added test case.
llvm-svn: 132612
Warn in cases such as "x + someCondition ? 42 : 0;",
where the condition expression looks arithmetic, and has
a right-hand side that looks boolean.
This (partly) addresses http://llvm.org/bugs/show_bug.cgi?id=9969
llvm-svn: 132565
In code such as "char* volatile const j()", Clang warns that "volatile
const" will be ignored. Make it point to the first ignored qualifier,
and simplify the code a bit.
llvm-svn: 132563
Sema::RequireCompleteExprType() a bit more, setting the point of
instantiation if needed, and skipping explicit specializations entirely.
llvm-svn: 132547
diagnostic group to cover the cases where we have definitively bad
behavior: dynamic classes.
It also rips out the existing support for POD-based checking. This
didn't work well, and triggered too many false positives. I'm looking
into a possibly more principled way to warn on the fundamental buggy
construct here. POD-ness isn't the critical aspect anyways, so a clean
slate is better. This also removes some silliness from the code until
the new checks arrive.
llvm-svn: 132534
of incomplete array type, attempt to complete the array type. This was
made much easier by Chandler's addition of RequireCompleteExprType(),
which I've tweaked (slightly) to improve the consistency of the
DeclRefExpr. Fixes PR7985.
llvm-svn: 132530
the template parameter, perform the checking as a "specified" template
argument rather than a "deduced" template argument; the latter implies
stricter type checking that is not permitted for default template
arguments.
Also, cleanup our handling of substitution of explicit template
arguments for a function template. We were actually performing some
substitution of default arguments at this point!
Fixes PR10069.
llvm-svn: 132529
+keyPathsForValuesAffecting<Key> completion was mislabeled as an
instance method, and +automaticallyNotifiesObserversOf<Key> was
missing entirely. Fixes <rdar://problem/9516762>.
llvm-svn: 132452
a file was modified since the time the PCH was created.
The parser is not fit to deal with stale PCHs, too many invariants do not hold up. rdar://9530587.
llvm-svn: 132389
tools that match on the C++ ASTs. The main interface is in ASTMatchers.h,
an example implementation of a tool that removes redundant .c_str() calls
is in the example RemoveCStrCalls.cpp.
Various contributions:
Zhanyong Wan, Chandler Carruth, Marcin Kowalczyk, Wei Xu, James Dennett.
llvm-svn: 132374
class type (or array thereof), eliminating some redundant checks
(thanks Eli!) and adding some tests where the behavior differs in
C++98/03 vs. C++0x.
llvm-svn: 132218
to be careful to emit landing pads that are always prepared to handle a
cleanup path. This is correct mostly because of the fix to the LLVM
inliner, r132200.
llvm-svn: 132209
so that it looks at the initializer of a local variable of class type
(or array thereof) to determine whether it's just an implicit
invocation of the trivial default constructor. Fixes PR10034.
llvm-svn: 132191
within class templates when they are necessary to complete the type of
the member. The canonical example is code like:
template <typename T> struct S {
static const int arr[];
static const int x;
static int f();
};
template <typename T> const int S<T>::arr[] = { 1, 2, 3 };
template <typename T> const int S<T>::x = sizeof(arr) / sizeof(arr[0]);
template <typename T> int S<T>::f() { return x; }
int x = S<int>::f();
We need to instantiate S<T>::arr's definition to pick up its initializer
and complete the array type. This involves new code to specially handle
completing the type of an expression where the type alone is
insufficient. It also requires *updating* the expression with the newly
completed type. Fortunately, all the other infrastructure is already in
Clang to do the instantiation, do the completion, and prune out the
unused bits of code that result from this instantiation.
This addresses the initial bug in PR10001, and will be a step to
fleshing out other cases where we need to work harder to complete an
expression's type. Who knew we still had missing C++03 "features"?
llvm-svn: 132172
parameter types to be ill-formed. However, it relies on the
completeness of method parameter types when producing metadata, e.g.,
for a protocol, leading IR generating to crash in such cases.
Since there's no real way to tighten down the semantics of Objective-C
here without breaking existing code, do something safe but lame:
suppress the generation of metadata when this happens.
Fixes <rdar://problem/9123036>.
llvm-svn: 132171
makes it into a special member function. This is very bad and can lead
to all sorts of nastiness including implicit member functions violating
the One Definition Rule. This should probably be made ill-formed in a
later version of the standard, but for now we'll just warn.
llvm-svn: 132104
type that turns one type into another. This is used as the basis to
implement __underlying_type properly - with TypeSourceInfo and proper
behavior in the face of templates.
llvm-svn: 132017
that the unevaluated subexpressions of &&, ||, and ? : are not
considered when determining whether the expression is a constant
expression. Also, turn the "used in its own initializer" warning into
a runtime-behavior warning, so that it doesn't fire when a variable is
used as part of an unevaluated subexpression of its own initializer.
Fixes PR9999.
llvm-svn: 131968
through sugared types when testing for TagTypes. This was the actual
cause of the only false positive in Clang+LLVM.
Next evaluation will be over a much larger selection of code including
large amounts of open source code.
llvm-svn: 131957
issues and also add a test.
We should now handle defaulted members of templates properly. No
comment as to whether or not this also holds for templated functions,
but defaulting those is kind of insane.
llvm-svn: 131938
fixes PR9965, but we're not out of the water yet, as we do not
successfully handle out-of-line definitions, due to my utter
misunderstanding of how we manage templates.
llvm-svn: 131920
Example:
class A { public: int f(); };
class B : public A { private: using A::f; };
class C : public B { private: using B::f; };
Here, B::f is private so this should fail in Standard C++, but because B::f refers to A::f which is public MSVC accepts it.
This fixes 1 error when parsing MFC code with clang.
llvm-svn: 131896
generator will give it something sufficient. This is important because
the mid-level optimizer doesn't know what alignment is required otherwise.
llvm-svn: 131879
header. Getting it in the wrong order generated incorrect line markers in -E
mode. In the testcase from PR9861 we used to generate:
# 1 "test.c" 2
# 1 "./foobar.h" 1
# 0 "./foobar.h"
# 0 "./foobar.h" 3
# 2 "test.c" 2
now we properly produce:
# 1 "test.c" 2
# 1 "./foobar.h" 1
# 1 "./foobar.h" 3
# 2 "test.c" 2
This fixes PR9861.
llvm-svn: 131871
minor issues along the way:
- Non-type template parameters of type 'std::nullptr_t' were not
permitted.
- We didn't properly introduce built-in operators for nullptr ==,
!=, <, <=, >=, or > as candidate functions .
To my knowledge, there's only one (minor but annoying) part of nullptr
that hasn't been implemented: catching a thrown 'nullptr' as a pointer
or pointer-to-member, per C++0x [except.handle]p4.
llvm-svn: 131813
non-POD/non-trivial object throuugh a C-style varargs. The warning
itself was default-mapped to error, but can be downgraded, but we were
treating it in Sema like a hard error, silently dropping the call.
Instead, treat this problem like a warning, and do what the warning
says we do: abort at runtime. To do so, we fake up a __builtin_trap()
expression that gets evaluated as part of the argument.
llvm-svn: 131805
should use a constructor to default-initialize a
variable. InitializationSequence knows the rules for default
initialization, better. Fixes <rdar://problem/8501008>.
llvm-svn: 131796
prints the file, line, and column of a diagnostic. We currently
support Clang's normal format, MSVC, and Vi formats.
Note that we no longer change the diagnostic format based on
-fms-extensions.
Patch by Andrew Fish!
llvm-svn: 131794
Type::isUnsignedIntegerOrEnumerationType(), which are like
Type::isSignedIntegerType() and Type::isUnsignedIntegerType() but also
consider the underlying type of a C++0x scoped enumeration type.
Audited all callers to the existing functions, switching those that
need to also handle scoped enumeration types (e.g., those that deal
with constant values) over to the new functions. Fixes PR9923 /
<rdar://problem/9447851>.
llvm-svn: 131735
to a warning, since apparently libstdc++'s debug mode does this (and
we can recover safely). Add a Fix-It to insert the "inline", just for kicks.
llvm-svn: 131732
Douglas Gregor