We would end up marking the vtable of the derived class as used for no
reason. Because the call itself is qualified, it is never virtual, and
the vtable of the derived class isn't helpful. We would end up rejecting
code that MSVC accepts for no benefit.
See http://crbug.com/413478
llvm-svn: 217910
constexpr function. Part of this fix is a tentative fix for an as-yet-unfiled
core issue (we're missing a prohibition against reading mutable members from
unions via a trivial constructor/assignment, since that doesn't perform an
lvalue-to-rvalue conversion on the members).
llvm-svn: 217852
In Parser::ParseCXXClassMemberDeclaration(), it was possible to change
isAccessDecl = NextToken().is(tok::kw_operator);
to
isAccessDecl = false;
and no tests would fail. Now there's coverage for this.
llvm-svn: 217519
This makes use of the recently-added @llvm.assume intrinsic to implement a
__builtin_assume(bool) intrinsic (to provide additional information to the
optimizer). This hooks up __assume in MS-compatibility mode to mirror
__builtin_assume (the semantics have been intentionally kept compatible), and
implements GCC's __builtin_assume_aligned as assume((p - o) & mask == 0). LLVM
now contains special logic to deal with assumptions of this form.
llvm-svn: 217349
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
"protected scope" is very unhelpful here and actively confuses users. Instead,
simply state the nature of the problem in the diagnostic: we cannot jump from
here to there. The notes explain nicely why not.
llvm-svn: 217293
Originally, self reference checking made a double pass over some expressions
to handle reference type checking. Now, allow HandleValue to also check
reference types, and fallback to Visit for unhandled expressions.
llvm-svn: 217203
before retrying the initialization to produce diagnostics. Otherwise, we may
fail to produce any diagnostics, and silently produce invalid AST in a -Asserts
build. Also add a note to this codepath to make it more clear why we were
trying to create a temporary.
llvm-svn: 217197
Scoped lockable objects (mutex guards) are implemented as if it is a
lock itself that is acquired upon construction and unlocked upon
destruction. As it if course needs to be used to actually lock down
something else (a mutex), it keeps track of this knowledge through its
underlying mutex field in its FactEntry.
The problem with this approach is that this only allows us to lock down
a single mutex, so extend the code to use a vector of underlying
mutexes. This, however, makes the code a bit more complex than
necessary, so subclass FactEntry into LockableFactEntry and
ScopedLockableFactEntry and move all the logic that differs between
regular locks and scoped lockables into member functions.
llvm-svn: 217016
don't mark the field as initialized until the next initializer instead of
instantly. Since this checker is AST based, statements are processed in tree
order instead of following code flow. This can result in different warnings
from just reordering the code. Also changed to use one checker per constructor
instead of creating a new checker per field.
class T {
int x, y;
// Already warns
T(bool b) : x(!b ? (1 + y) : (y = 5)) {}
// New warning added here, previously (1 + y) comes after (y = 5) in the AST
// preventing the warning.
T(bool b) : x(b ? (y = 5) : (1 + y)) {}
};
llvm-svn: 216641
Fix r216438 to catch more complicated self-initialized in std::move. For
instance, "Foo f = std::move(cond ? OtherFoo : (UNUSED_VALUE, f));"
Make sure that BinaryConditionalOperator, ConditionalOperator, BinaryOperator
with comma operator, and OpaqueValueExpr perform the correct usage forwarding
across the three uninitialized value checkers.
llvm-svn: 216627
This shouldn't really be allowed, but it comes up in real code (see PR). As
long as the decl hasn't been used there's no technical difficulty in supporting
it, so downgrade the error to a warning.
Differential Revision: http://reviews.llvm.org/D5087
llvm-svn: 216619
the no-arguments case. Don't expand this to an __attribute__((nonnull(A, B,
C))) attribute, since that does the wrong thing for function templates and
varargs functions.
In passing, fix a grammar error in the diagnostic, a crash if
__attribute__((nonnull(N))) is applied to a varargs function,
a bug where the same null argument could be diagnosed multiple
times if there were multiple nonnull attributes referring to it,
and a bug where nonnull attributes would not be accumulated correctly
across redeclarations.
llvm-svn: 216520
We would previously assert (a decl cannot have two DLL attributes) on this code:
template <typename T> struct __declspec(dllimport) S { T f() { return T(); } };
template struct __declspec(dllexport) S<int>;
The problem was that when instantiating, we would take the attribute from the
template even if the instantiation itself already had an attribute.
Also, don't inherit DLL attributes from the template to its members before
instantiation, as the attribute may change.
I couldn't figure out what MinGW does here, so I'm leaving that open. At least
we're not asserting anymore.
llvm-svn: 216340
The situation it is warning about (see PR20725) is not very likely
to be a real problem, and it is unclear what action the user should take
if the warning does fire.
llvm-svn: 216283
Normally we mark all members of exported classes referenced to get them emitted.
However, MSVC doesn't do this for class templates that are implicitly specialized or
just have an explicit instantiation declaration. For such specializations, the members
are emitted when referenced.
The exception is the case when the dllexport attribute is propagated from a base class
to a base class template that doesn't have an explicit attribute: in this case all
methods of the base class template do get instantiated.
llvm-svn: 216145
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
-Wthread-safety umbrella flag, pending updates to documentation. The flag
works, but is likely to be confusing to existing users of -Wthread-safety.
llvm-svn: 215679
It doesn't really make sense to try and do stuff with #pragma init_seg
when targeting non-Microsoft platforms; notions like library vs user
initializers don't exist for other targets.
This fixes PR20639.
llvm-svn: 215618
it. Diagnose with recovery if it appears after a function parameter that was
obviously supposed to be a parameter pack. Otherwise, warn if it immediately
follows a function parameter pack, because the user most likely didn't intend
to write a parameter pack followed by a C-style varargs ellipsis.
This warning can be syntactically disabled by using ", ..." instead of "...".
llvm-svn: 215408
macro arguments.
Previously, these warnings skipped any code in a macro expansion. Preform an
additional check and warn when the expression and context locations are both
in the macro argument.
The most obvious case not caught is passing a pointer directly to a macro,
i.e 'assert(&array)' but 'assert(&array && "valid array")' is caught. This is
because macro arguments are not typed and the conversion happens inside the
macro.
llvm-svn: 215251
As we only create temp dtor decision branches when a temp dtor needs to
be run (as opposed to for each logical branch in the original
expression), we must include the information about all previous logical
branches when we annotate the temp dtor decision branch.
llvm-svn: 215188
MSVC doesn't decide what the inheritance model for a returned member
pointer *until* a call expression returns it.
This fixes PR20017.
llvm-svn: 215164
If the truth value of a LHS is known, we can build the knowledge whether
a temporary destructor is executed or not into the CFG. This is needed
by the return type analysis.
llvm-svn: 215118
Changes to the original patch:
- model the CFG for temporary destructors in conditional operators so that
the destructors of the true and false branch are always exclusive. This
is necessary because we must not have impossible paths for the path
based analysis to work.
- add multiple regression tests with ternary operators
Original description:
Fix modelling of non-lifetime-extended temporary destructors in the
analyzer.
Changes to the CFG:
When creating the CFG for temporary destructors, we create a structure
that mirrors the branch structure of the conditionally executed
temporary constructors in a full expression.
The branches we create use a CXXBindTemporaryExpr as terminator which
corresponds to the temporary constructor which must have been executed
to enter the destruction branch.
2. Changes to the Analyzer:
When we visit a CXXBindTemporaryExpr we mark the CXXBindTemporaryExpr as
executed in the state; when we reach a branch that contains the
corresponding CXXBindTemporaryExpr as terminator, we branch out
depending on whether the corresponding CXXBindTemporaryExpr was marked
as executed.
llvm-svn: 215096
This matches MSVC's logic, which seems to be that when the friend
declaration is qualified, it cannot be a declaration of a new symbol
and so the dll linkage doesn't change.
Differential Revision: http://reviews.llvm.org/D4764
llvm-svn: 214774
or a class derived from T. We already supported this when initializing
_Atomic(T) from T for most (and maybe all) other reasonable values of T.
llvm-svn: 214390
The new flag, WantFunctionLikeCasts, covers a subset of the keywords
covered by WantTypeSpecifiers that can be used in casts that look like
function calls, e.g. "return long(5);", while excluding the keywords
like "enum" and "const" that would be included when WantTypeSpecifiers
is true but cannot be used in something that looks like a function call.
llvm-svn: 214109
til::SExpr. This is a large patch, with many small changes to pretty printing
and expression lowering to make the new SExpr representation equivalent in
functionality to the old.
llvm-svn: 214089
lambda expressions (other than their capture initializers) nor blocks. Do walk
into default argument expressions and default initializer expressions.
These bugs were causing us to produce broken CFGs whenever a lambda expression
was used to initialize a libstdc++ std::function object!
llvm-svn: 214050
The class seems to have an invariant that Entries is non-empty if
Invalid is false. It appears this method was previously private, and
all internal uses checked Invalid. Now there is an external caller, so
check Invalid to avoid array OOB underflow.
Fixes PR20420.
llvm-svn: 213816
This tweaks the diagnostic wording slighly, and adds a fixit on a note.
An alternative would be to add the fixit directly on the diagnostic, see
the review thread linked to from the bug for a few notes on that approach.
llvm-svn: 213725
being declared, not at the end. When pretty-printing a non-type template
parameter, put the name of the parameter in the middle of the type, not at the
end.
llvm-svn: 213718
Windows ARM indicates __va_start as a variadic function. However, the function
itself is treated as having 4 formal arguments:
- (out) pointer to the va_list
- (in) address of the last named argument
- (in) slot size for the type of the last argument
- address of the last named argument
The last argument does not seem to have any bearing on codegen, and thus is not
explicitly type checked at this point.
Unlike the previous handling for __va_start, it does not currently validate if
the parameter is the last named parameter (it seems that MSVC currently accepts
this).
llvm-svn: 213595
If function parameters have default values, and that of the second
parameter is parsed with errors, function declaration would have
a parameter without default value that follows a parameter with
that. Such declaration breaks logic of selecting overloaded
function. As a solution, put opaque object as default value in such case.
This patch fixes PR20055.
Differential Revision: http://reviews.llvm.org/D4378
llvm-svn: 213594
Summary:
This pragma is very rare. We could *hypothetically* lower some uses of
it down to @llvm.global_ctors, but given that GlobalOpt isn't able to
optimize prioritized global ctors today, there's really no point.
If we wanted to do this in the future, I would check if the section used
in the pragma started with ".CRT$XC" and had up to two characters after
it. Those two characters could form the 16-bit initialization priority
that we support in @llvm.global_ctors. We would have to teach LLVM to
lower prioritized global ctors on COFF as well.
This should let us compile some silly uses of this pragma in WebKit /
Blink.
Reviewers: rsmith, majnemer
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D4549
llvm-svn: 213593
ExtWarn/Warnings. Mostly the name of the warning was changed to match the
semantics, but in the PR20356 cases, the warning was about valid code, so the
diagnostic was changed from ExtWarn to Warning instead.
llvm-svn: 213443
-- a constructor list initialization that unpacked an initializer list into
constructor arguments and
-- a list initialization that created as std::initializer_list and passed it
as the first argument to a constructor
in the AST. Use this flag while instantiating templates to provide the right
semantics for the resulting initialization.
llvm-svn: 213224
constructor (and pass it an implicitly-generated std::initializer_list object),
be sure to mark the resulting construction as list-initialization. This fixes
an assert in template instantiation where we previously thought we'd got direct
non-list initialization without any parentheses.
llvm-svn: 213201
We've decided to make the core rewriter class and PP rewriters mandatory.
They're only a few hundred lines of code in total and not worth supporting as a
distinct build configuration, especially since doing so disables key compiler
features.
This reverts commit r213150.
Revert "clang/test: Introduce the feature "rewriter" for --enable-clang-rewriter."
This reverts commit r213148.
Revert "Move clang/test/Frontend/rewrite-*.c to clang/test/Frontend/Rewriter/"
This reverts commit r213146.
llvm-svn: 213159
Recognize additional cases, when '::' is mistyped as ':'.
This is a fix to RP18587 - colons have too much protection in member-declarations
Review is tracked by http://reviews.llvm.org/D3653.
This is an attempt to recommit the fix, initially committed as r212957 but then
reverted in r212965 as it broke self-build. In the updated patch ParseDirectDeclarator
turns on colon protection in for context as well.
llvm-svn: 213120
Otherwise, multiple errors such as having unknown identifiers for two
arguments won't be diagnosed properly (e.g. only the first one would
have a diagnostic message if typo correction fails even though both
would be diagnosed if typo correction suggests a replacement).
llvm-svn: 213003
array prvalue), treat that as a direct binding. Only the class prvalue case
needs to be excluded here; the rest are extensions anyway, so we can treat them
as we would in C++11.
llvm-svn: 212978
We don't have a style guide for diagnostic messages, but convention strongly
favours the forms:
'attribute is not supported', 'unsupported attribute'
We generally avoid:
'attribute is unsupported', 'non-supported attribute'
llvm-svn: 212972
This reverts commit r212957. It broke the self-host on code like this
from LLVM's option library:
for (auto Arg: filtered(Id0, Id1, Id2))
llvm-svn: 212965
Recognize additional cases, when '::' is mistyped as ':'.
This is a fix to RP18587 - colons have too much protection in member-declarations.
Differential Revision: http://reviews.llvm.org/D3653
llvm-svn: 212957
a function pointer is neither better nor worse than binding a function lvalue
to a function rvalue reference. Don't get confused and think that both bindings
are binding to a function lvalue (which would make the lvalue form win); the
const reference is binding to an rvalue.
The "real" bug in PR20218 is still present: we're getting the wrong answer from
template argument deduction, and that's what leads us to this weird overload
set.
llvm-svn: 212916
The relevant portion of C++ standard says [namespace.memdef]p3:
If the name in a friend declaration is neither qualified nor a
template-id and the declaration is a function or an
elaborated-type-specifier, the lookup to determine whether the entity
has been previously declared shall not consider any scopes outside the
innermost enclosing namespace.
MSVC does not implement that rule for types. If there is a type in an
enclosing namespace, they consider an unqualified tag declaration with
the same name to be a redeclaration of the type from another namespace.
Implementing compatibility is a simple matter of disabling our
implementation of this rule for types, which was added in r177473.
Reviewers: rsmith
Differential Revision: http://reviews.llvm.org/D4443
llvm-svn: 212784
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
r210091 made initialization checking more strict in c++11 mode. LWG2193 is
about changing standard libraries to still be valid under these new rules,
but older libstdc++ (e.g. libstdc++4.6 in -D_GLIBCXX_DEBUG=1 mode, or stlport)
do not implement that yet. So fall back to the C++03 semantics for container
classes in system headers below the std namespace.
llvm-svn: 212238
Fixes PR20110, where Clang hits an assertion failure when it expects that the
sub-expression of a bit cast to pointer to also be a pointer, but gets a value
instead.
Differential Revision: http://reviews.llvm.org/D4280
llvm-svn: 212160
Previously dllimport variables inside of template arguments relied on
not using the C++11 codepath when -fms-compatibility was set.
While this allowed us to achieve compatibility with MSVC, it did so at
the expense of MingW.
Instead, try to use the DeclRefExpr we dig out of the template argument.
If it has the dllimport attribute, accept it and skip the C++11
null-pointer check.
llvm-svn: 211766
This is a follow-up to David's r211677. For the following code,
we would end up referring to 'foo' in the initializer for 'arr',
and then fail to link, because 'foo' is dllimport and needs to be
accessed through the __imp_?foo.
__declspec(dllimport) extern const char foo[];
const char* f() {
static const char* const arr[] = { foo };
return arr[0];
}
Differential Revision: http://reviews.llvm.org/D4299
llvm-svn: 211736
Consider the following code:
template <typename T> class Base {};
class __declspec(dllexport) class Derived : public Base<int> {}
When the base of an exported or imported class is a class template
specialization, MSVC will propagate the dll attribute to the base.
In the example code, Base<int> becomes a dllexported class.
This commit makes Clang do the proopagation when the base hasn't been
instantiated yet, and warns about it being unsupported otherwise.
This is different from MSVC, which allows changing a specialization
back and forth between dllimport and dllexport and seems to let the
last one win. Changing the dll attribute after instantiation would be
hard for us, and doesn't seem to come up in practice, so I think this
is a reasonable limitation to have.
MinGW doesn't do this kind of propagation.
Differential Revision: http://reviews.llvm.org/D4264
llvm-svn: 211725
Types defined in function prototype are diagnosed earlier in C++ compilation.
They are put into declaration context where the prototype is introduced. Later on,
when FunctionDecl object is created, these types are moved into the function context.
This patch fixes PR19018 and PR18963.
Differential Revision: http://reviews.llvm.org/D4145
llvm-svn: 211718
The C++ language requires that the address of a function be the same
across all translation units. To make __declspec(dllimport) useful,
this means that a dllimported function must also obey this rule. MSVC
implements this by dynamically querying the import address table located
in the linked executable. This means that the address of such a
function in C++ is not constant (which violates other rules).
However, the C language has no notion of ODR nor does it permit dynamic
initialization whatsoever. This requires implementations to _not_
dynamically query the import address table and instead utilize a wrapper
function that will be synthesized by the linker which will eventually
query the import address table. The effect this has is, to say the
least, perplexing.
Consider the following C program:
__declspec(dllimport) void f(void);
typedef void (*fp)(void);
static const fp var = &f;
const fp fun() { return &f; }
int main() { return fun() == var; }
MSVC will statically initialize "var" with the address of the wrapper
function and "fun" returns the address of the actual imported function.
This means that "main" will return false!
Note that LLVM's optimizers are strong enough to figure out that "main"
should return true. However, this result is dependent on having
optimizations enabled!
N.B. This change also permits the usage of dllimport declarators inside
of template arguments; they are sufficiently constant for such a
purpose. Add tests to make sure we don't regress here.
llvm-svn: 211677
The address of dllimport functions can be accessed one of two ways:
- Through the IAT which is symbolically referred to with a symbol
starting with __imp_.
- Via the wrapper-function which ends up calling through the __imp_
symbol.
The problem with using the wrapper-function is that it's address will
not compare as equal in all translation units. Specifically, it will
compare unequally with the translation unit which defines the function.
This fixes PR19955.
llvm-svn: 211570
The address of dllimport variables isn't something that can be
meaningfully used in a constexpr context and isn't suitable for
evaluation at load-time. They require loads from memory to properly
evaluate.
This fixes PR19955.
Differential Revision: http://reviews.llvm.org/D4250
llvm-svn: 211568
Something went wrong with r211426, it is an older version of this code
and should not have been committed. It was reverted with r211434.
Original commit message:
We didn't properly implement support for the sized integer suffixes.
Suffixes like i16 were essentially ignored instead of mapping them to
the appropriately sized integer type.
This fixes PR20008.
Differential Revision: http://reviews.llvm.org/D4132
llvm-svn: 211441
This reverts commit r211426.
This broke the arm bots. The crash can be reproduced on X86 by running.
./bin/clang -cc1 -fsyntax-only -verify -fms-extensions ~/llvm/clang/test/Lexer/ms-extensions.c -triple arm-linux
llvm-svn: 211434
We didn't properly implement support for the sized integer suffixes.
Suffixes like i16 were essentially ignored instead of mapping them to
the appropriately sized integer type.
This fixes PR20008.
Differential Revision: http://reviews.llvm.org/D4132
llvm-svn: 211426
CL permits static redeclarations to follow extern declarations. The
storage specifier on the latter declaration has no effect.
This fixes PR20034.
Differential Revision: http://reviews.llvm.org/D4149
llvm-svn: 211238
Previously we would do the access check from the context of
MarkVTableUsed.
Also update this test to C++11, since that is typically used with the MS
C++ ABI.
Fixes PR20005.
llvm-svn: 210850
The only external/visible functional change that fell out of this
refactoring is that there was one less case where the typo caching
and/or counting didn't work properly. The result is that a test case
had to be moved from typo-correction.cpp to typo-correction-pt2.cpp
to avoid the hard-coded limit on per file/TU typo correction attempts.
llvm-svn: 210669
expression of array-of-unknown-bound type, don't try to complete the array
bound, and return the alignment of the element type rather than 1.
llvm-svn: 210608
We would previously end up with an error when instantiating the
following template:
template <typename> struct __declspec(dllimport) S {
void foo() = delete;
};
S<int> s;
error: attribute 'dllimport' cannot be applied to a deleted function
llvm-svn: 210550
This allows us to compile the following kind of code, which occurs in MSVC
headers:
template <typename> struct S {
__declspec(dllimport) static int x;
};
template <typename T> int S<T>::x;
The definition works similarly to a dllimport inline function definition and
gets available_externally linkage.
Differential Revision: http://reviews.llvm.org/D3998
llvm-svn: 210141
elements from {}, rather than value-initializing them. This permits calling an
initializer-list constructor or constructing a std::initializer_list object.
(It would also permit initializing a const reference or rvalue reference if
that weren't explicitly prohibited by other rules.)
llvm-svn: 210091
just the extremely specific case of a trailing array element that couldn't be
initialized because the default constructor for the element type is deleted.
Also reword the diagnostic to better match our other context diagnostics and to
prepare for the implementation of core issue 1070.
llvm-svn: 210083
We should treat tentative definitions as undefined for the purpose of
ODR-use linkage checking.
This broke somewhere around r149731 when tests were disabled.
Note that test coverage for these diagnostics is generally lacking due to a
separate issue (PR19910: Don't suppress unused/undefined warnings when there
are errors).
llvm-svn: 209996
http://llvm.org/bugs/show_bug.cgi?id=18498
This code was resulting in a crash:
auto L = [](auto ... v) { };
L.operator()<int>(3);
The reason is that the partially-substituted-pack is incorrectly retained within the current-instantiation-scope during template-argument-finalization, and because lambda's are local, there parent instantiation scopes are merged, which leads to the expansion-pattern being retained in the finalized specialization.
This patch ensures that once we have finalized deduction of a parameter-pack, we remove the partially-substituted-pack so that it doesn't cause CheckParameterPacksForExpansion to incorrectly inform the caller that it needs to retain the expansion pattern.
Thanks to Richard Smith for the review!
http://reviews.llvm.org/D2135
llvm-svn: 209992
This implements the central part of support for dllimport/dllexport on
classes: allowing the attribute on class declarations, inheriting it
to class members, and forcing emission of exported members. It's based
on Nico Rieck's patch from http://reviews.llvm.org/D1099.
This patch doesn't propagate dllexport to bases that are template
specializations, which is an interesting problem. It also doesn't
look at the rules when redeclaring classes with different attributes,
I'd like to do that separately.
Differential Revision: http://reviews.llvm.org/D3877
llvm-svn: 209908
http://llvm.org/bugs/show_bug.cgi?id=19876
The following C++1y code results in a crash:
struct X {
int m = 10;
int n = [this](auto) { return m; }(20);
};
When implicitly instantiating the generic lambda's call operator specialization body, Sema is unable to determine the current 'this' type when transforming the MemberExpr 'm' - since it looks for the nearest enclosing FunctionDeclDC - which is obviously null.
I considered two ways to fix this:
1) In InstantiateFunctionDefinition, when the context is saved after the lambda scope info is created, retain the 'this' pointer.
2) Teach getCurrentThisType() to recognize it is within a generic lambda within an NSDMI/default-initializer and return the appropriate this type.
I chose to implement #2 (though I confess I do not have a compelling reason for choosing it over #1).
Richard Smith accepted the patch:
http://reviews.llvm.org/D3935
Thank you!
llvm-svn: 209874
This patch implements support for selectively disabling optimizations on a
range of function definitions through a pragma. The implementation is that
all function definitions in the range are decorated with attribute
'optnone'.
#pragma clang optimize off
// All function definitions in here are decorated with 'optnone'.
#pragma clang optimize on
// Compilation resumes as normal.
llvm-svn: 209510
This is a GNU attribute that causes calls within the attributed function
to be inlined where possible. It is implemented by giving such calls the
alwaysinline attribute.
Differential Revision: http://reviews.llvm.org/D3816
llvm-svn: 209217
For targeting i686-msvc, declarations are seen as thiscall like;
void (template_test::S::*)(const int &) __attribute__((thiscall))
void (template_test::S::*)(int) __attribute__((thiscall))
It didn't affect x86_64-msvc.
llvm-svn: 209212
The attribute emitter was using FunctionTemplate to map the diagnostic to "functions or methods", but that isn't a particularly clear diagnostic in these cases anyway (since they do not apply to ObjC methods). Updated the attribute emitter to remove custom logic for FunctionTemplateDecl, and updated the test cases for the change in diagnostic wording.
llvm-svn: 209209
This is a GNU attribute that allows split stacks to be turned off on a
per-function basis.
Differential Revision: http://reviews.llvm.org/D3817
llvm-svn: 209167
The conventional form is '<action> to silence this warning'.
Also call the diagnostic an 'issue' rather than a 'message' because the latter
term is more widely used with reference to message expressions.
llvm-svn: 209052
caused us to perform copy-initialization for the parameters of an allocation
function called by a new-expression multiple times, resulting in us rejecting
allocations that passed non-copyable parameters (and much worse things in
MSVC compat mode, where we potentially called this function multiple times).
llvm-svn: 208724
The base class is the culprit/risk here - a sealed/final derived class
with virtual functions and a non-virtual dtor can't accidentally be
polymorphically destroyed (if the base class's dtor is protected - which
also suppresses this warning).
llvm-svn: 208449
This lets us diagnose and perform more complete semantic analysis when faced
with errors in the function body or declaration.
By recovering here we provide more consistent diagnostics, particularly during
interactive editing.
llvm-svn: 208394
A template declaration of a template name can be null in case we have a dependent name or a set of function templates.
Hence use dyn_cast_or_null instead of dyn_cast. Also improve the diagnostic emitted in this case.
llvm-svn: 208313
C++. This seems like a pointless (and indeed harmful) restriction to me, so
I've suggested removing it to -core and disabled this diagnostic by default.
llvm-svn: 208254
Libraries specify enabled/disabled features using macro defs of 0/1, in such cases the -Wconstant-logical-operand
is noise.
rdar://15410291
llvm-svn: 207386
We never aka vector types because our attributed syntax for it is less
comprehensible than the typedefs. This leaves the user in the dark when
the typedef isn't named that well.
Example:
v2s v; v4f w;
w = v;
The naming in this cases isn't even that bad, but the error we give is
useless without looking up the actual typedefs.
t.c:6:5: error: assigning to 'v4f' from incompatible type 'v2s'
Now:
t.c:6:5: error: assigning to 'v4f' (vector of 4 'float' values) from
incompatible type 'v2s' (vector of 2 'int' values)
We do this for all diagnostics that print a vector type.
llvm-svn: 207267
-Wc++11-compat-deprecated-writable-strings. It's neither a C++11 compatibility
warning nor a deprecated feature, it's just ill-formed.
In passing, add that warning to -Wdeprecated, where it belongs.
llvm-svn: 206833
Warn on std::abs() with unsigned argument.
Suggest std::abs as replacement for the C absolute value functions.
Suggest C++ headers if the specific std::abs overload is not found.
llvm-svn: 206340
Parse of nested name spacifier is modified so that it properly recovers
if colon is mistyped as double colon in case statement.
This patch fixes PR15133.
Differential Revision: http://llvm-reviews.chandlerc.com/D2870
llvm-svn: 206135
If the C-style type cast is applied to the overloaded
function and the destination type is function type,
then Clang will crash with assertion failure. For example,
void foo(int);
void foo(int, int);
void bar() {
typedef void (ft)(int);
ft p = (ft)foo;
}
In this case, the overloaded function foo will be cast to
a function type, which should be considered as an error.
But, unfortunately, since the function resolution is using
canonical type, the matched function will be returned, and
result in SEGV.
This patch fixes this issue by removing the assertion and
add some error diagnostics as the one in static_cast.
llvm-svn: 206133
declaration is not visible. Previously we didn't find hidden friend names in
this redeclaration lookup, because we forgot to treat it as a redeclaration
lookup. Conversely, we did find some local extern names, but those don't
actually conflict with a namespace-scope using declaration, because the only
conflicts we can get are scope conflicts, not conflicts due to the entities
being members of the same namespace.
llvm-svn: 206011
which warns on compound conditionals that always evaluate to the same value.
For instance, (x > 5 && x < 3) will always be false since no value for x can
satisfy both conditions.
This patch also changes the CFG to use these tautological values for better
branch analysis. The test for -Wunreachable-code shows how this change catches
additional dead code.
Patch by Anders Rönnholm.
llvm-svn: 205665
obviously won't work. Specifically, don't suggest methods (static or
not) from unrelated classes when the expression is a method call
through a specific object.
llvm-svn: 205653
better. This warning will now trigger on the following conditionals:
bool b;
int i;
if (b > 1) {} // always false
if (0 <= (i > 5)) {} // always true
if (-1 > b) {} // always false
Patch by Per Viberg.
llvm-svn: 205608
meaningful to odr-use the VarDecl inside a variable template. (Separately, it'd
be nice to track referenced-ness for templates, and warn on unused ones, but
that's really a distinct issue...)
Move a test that generates and tests a warning-suppressing error out to its own
test file, so it doesn't have weird effects on the other tests in the same file.
llvm-svn: 205448
For namespaces, this is consistent with mangling and GCC's debug info
behavior. For structs, GCC uses <anonymous struct> but we prefer
consistency between all anonymous entities but don't want to confuse
them with template arguments, etc, so we'll just go with parens in all
cases.
llvm-svn: 205398
While investigating some debug info issues, Eric and I came across a
particular template case where the location of a decl was quite
different from the range of the same decl. It might've been rather
helpful if the dumper had actually showed us this.
llvm-svn: 205396
A redeclaration may not add dllimport or dllexport attributes. dllexport is
sticky and can be omitted on redeclarations while dllimport cannot.
llvm-svn: 205197
The exception is return statements that include control-flow,
which are clearly doing something "interesting".
99% of the cases I examined for -Wunreachable-code that fired
on return statements were not interesting enough to warrant
being in -Wunreachable-code by default. Thus the move to
include them in -Wunreachable-code-return.
This simplifies a bunch of logic, including removing the ad hoc
logic to look for std::string literals.
llvm-svn: 204307
Also relax unreachable 'break' and 'return' to not check for being
preceded by a call to 'noreturn'. That turns out to not be so
interesting in practice.
llvm-svn: 204000
Recent work on -Wunreachable-code has focused on suppressing uninteresting
unreachable code that center around "configuration values", but
there are still some set of cases that are sometimes interesting
or uninteresting depending on the codebase. For example, a dead
"break" statement may not be interesting for a particular codebase,
potentially because it is auto-generated or simply because code
is written defensively.
To address these workflow differences, -Wunreachable-code is now
broken into several diagnostic groups:
-Wunreachable-code: intended to be a reasonable "default" for
most users.
and then other groups that turn on more aggressive checking:
-Wunreachable-code-break: warn about dead break statements
-Wunreachable-code-trivial-return: warn about dead return statements
that return "trivial" values (e.g., return 0). Other return
statements that return non-trivial values are still reported
under -Wunreachable-code (this is an area subject to more refinement).
-Wunreachable-code-aggressive: supergroup that enables all these
groups.
The goal is to eventually make -Wunreachable-code good enough to
either be in -Wall or on-by-default, thus finessing these warnings
into different groups helps achieve maximum signal for more users.
TODO: the tests need to be updated to reflect this extra control
via diagnostic flags.
llvm-svn: 203994
This can possibly be refined later, but right now the experience
is so incomprehensible for a user to understand what is going on
this isn't a useful warning.
llvm-svn: 203336
This patch fixes PR18964. In linkage computation, assertion fails when
an old invalid declaration's linkage mismatches with the current
decl's one.
llvm-svn: 203168
I have mixed feelings about this one. It's used all over the codebase,
and is analogous to the current heuristic for ordinary C string literals.
This requires some ad hoc pattern matching of the AST. While the
test case mirrors what we see std::string in libc++, it's not really
testing the libc++ headers.
llvm-svn: 203091
Sometimes do..while() is used to create a scope that can be left early.
In such cases, the unreachable 'while()' test is not usually interesting
unless it actually does something that is observable.
llvm-svn: 203051
Summary:
This is needed to allow MSVC's <atomic> header to properly parse.
It uses _Atomic as a class-id.
Reviewers: rnk
Reviewed By: rnk
CC: cfe-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D2948
llvm-svn: 202901
const char *format = "%s";
std::experimental::string_view view = "foo";
printf(format, view);
In this case, not only warn about a class type being used here, but also suggest that calling c_str() might be a good idea.
llvm-svn: 202461
or virtual functions, but permit that error to be downgraded to
a warning (with -Wno-error=incompatible-ms-struct), and officially
support this kind of dual, ABI-mixing layout.
The basic problem here is that projects which use ms_struct are often
not very circumspect about what types they annotate; for example,
some projects enable the pragma in a prefix header and then only
selectively disable it around system header inclusions. They may
only care about binary compatibility with MSVC for a subset of
those structs, but that doesn't mean they have no binary
compatibility concerns at all for the rest; thus we are essentially
forced into supporting this hybrid ABI. But it's reasonable for
us to at least point out the places where we're not making
any guarantees.
The original diagnostic was for dynamic classes, i.e. those with
virtual functions or virtual bases; I've extended it to include
all classes with bases, because we are not actually making any
attempt to duplicate MSVC's base subobject layout in ms_struct
(and it is indeed quite different from Itanium, even for
non-virtual bases).
rdar://16178895
llvm-svn: 202427
null comparison when the pointer is known to be non-null.
This catches the array to pointer decay, function to pointer decay and
address of variables. This does not catch address of function since this
has been previously used to silence a warning.
Pointer to bool conversion is under -Wbool-conversion.
Pointer to null comparison is under -Wtautological-pointer-compare, a sub-group
of -Wtautological-compare.
void foo() {
int arr[5];
int x;
// warn on these conditionals
if (foo);
if (arr);
if (&x);
if (foo == null);
if (arr == null);
if (&x == null);
if (&foo); // no warning
}
llvm-svn: 202216
The warnings fall into three groups.
1) Using an absolute value function of the wrong type, for instance, using the
int absolute value function when the argument is a floating point type.
2) Using the improper sized absolute value function, for instance, using abs
when the argument is a long long. llabs should be used instead.
From these two cases, an implicit conversion will occur which may cause
unexpected behavior. Where possible, suggest the proper absolute value
function to use, and which header to include if the function is not available.
3) Taking the absolute value of an unsigned value. In addition to this warning,
suggest to remove the function call. This usually indicates a logic error
since the programmer assumed negative values would have been possible.
llvm-svn: 202211
- Don't emit anything when we encounter a call to a conversion operator.
"bar(a & b)" instead of "bar(a & b.operator int())"
This preserves the semantics and is still idempotent if we print the AST multiple times.
- Properly print declarations of conversion operators.
"explicit operator bool();" instead of "bool operator _Bool();"
PR18776.
llvm-svn: 202167
Reid Kleckner