Without this, -Wunused-local-typedef would incorrectly warn on the two typedefs
in this program:
void foo() {
struct A {};
struct B : public A {
typedef A INHERITED;
B() : INHERITED() {}
typedef B SELF;
B(int) : SELF() {}
};
}
llvm-svn: 221765
This is a new form of expression of the form:
(expr op ... op expr)
where one of the exprs is a parameter pack. It expands into
(expr1 op (expr2onwards op ... op expr))
(and likewise if the pack is on the right). The non-pack operand can be
omitted; in that case, an empty pack gives a fallback value or an error,
depending on the operator.
llvm-svn: 221573
Trying to import or export such classes doesn't make sense, and Clang
would assert trying to export vtables for them.
This is consistent with how we treat functions with internal linkage,
but it is stricter than MSVC so we may have to back down if it breaks
real code.
llvm-svn: 221160
It turns out that MinGW never dllimports of exports inline functions.
This means that code compiled with Clang would fail to link with
MinGW-compiled libraries since we might try to import functions that
are not imported.
To fix this, make Clang never dllimport inline functions when targeting
MinGW.
llvm-svn: 221154
but MSABI was never defined in the test. It seems we are erroring
on code that we should be accepting when compiling for MSVC compatibility.
This should make the test less confusing until PR21406 is fixed.
llvm-svn: 220825
This includes adding the new TypoExpr-based lazy typo correction to
LookupMemberExprInRecord as an alternative to the existing eager typo
correction.
llvm-svn: 220698
Wire it through everywhere we have support for fastcall, essentially.
This allows us to parse the MSVC "14" CTP headers, but we will
miscompile them because LLVM doesn't support __vectorcall yet.
Reviewed By: Aaron Ballman
Differential Revision: http://reviews.llvm.org/D5808
llvm-svn: 220573
If a templated class is not instantiated, then the AST for it could be missing
some things that would throw the field checker off. Wait until specialization
before emitting these warnings.
llvm-svn: 220363
complete object to a pointer to the start of another complete object does
not evaluate to the constant 'false'. All other comparisons between the
addresses of subobjects of distinct complete objects still do.
llvm-svn: 220343
A second instance of attributed types escaped the previous change, identified
thanks to Richard Smith! When deducing the void case, we would also assume that
the type would not be attributed. Furthermore, properly handle multiple
attributes being applied to a single TypeLoc.
Properly handle this case and future-proof a bit by ignoring parenthesis
further. The test cases do use the additional parenthesis to ensure that this
case remains properly handled.
Addresses post-commit review comments from Richard Smith to SVN r219851.
llvm-svn: 219974
Specifically, avoid typo-correcting the variable name into a type before
typo-correcting the actual type name in the declaration. Doing so
results in a very unpleasant cascade of errors, with the typo correction
of the actual type name being buried in the middle.
llvm-svn: 219732
and !=) to support mixed complex and real operand types.
This requires removing an assert from SemaChecking, and adding support
both to the constant evaluator and the code generator to synthesize the
imaginary part when needed. This seemed somewhat cleaner than having
just the comparison operators force real-to-complex conversions.
I've added test cases for these operations. I'm really terrified that
there were *no* tests in-tree which exercised this.
This turned up when trying to build R after my change to the complex
type lowering.
llvm-svn: 219570
operators where one type is a C complex type, and to emit both the
efficient and correct implementation for complex arithmetic according to
C11 Annex G using this extra information.
For both multiply and divide the old code was writing a long-hand
reduced version of the math without any of the special handling of inf
and NaN recommended by the standard here. Instead of putting more
complexity here, this change does what GCC does which is to emit
a libcall for the fully general case.
However, the old code also failed to do the proper minimization of the
set of operations when there was a mixed complex and real operation. In
those cases, C provides a spec for much more minimal operations that are
valid. Clang now emits the exact suggested operations. This change isn't
*just* about performance though, without minimizing these operations, we
again lose the correct handling of infinities and NaNs. It is critical
that this happen in the frontend based on assymetric type operands to
complex math operations.
The performance implications of this change aren't trivial either. I've
run a set of benchmarks in Eigen, an open source mathematics library
that makes heavy use of complex. While a few have slowed down due to the
libcall being introduce, most sped up and some by a huge amount: up to
100% and 140%.
In order to make all of this work, also match the algorithm in the
constant evaluator to the one in the runtime library. Currently it is
a broken port of the simplifications from C's Annex G to the long-hand
formulation of the algorithm.
Splitting this patch up is very hard because none of this works without
the AST change to preserve non-complex operands. Sorry for the enormous
change.
Follow-up changes will include support for sinking the libcalls onto
cold paths in common cases and fastmath improvements to allow more
aggressive backend folding.
Differential Revision: http://reviews.llvm.org/D5698
llvm-svn: 219557
Summary: This fixes PR21235.
Test Plan: Includes an automated test.
Reviewers: hansw
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D5718
llvm-svn: 219551
Assertion failed: "Computed __func__ length differs from type!"
Reworked PredefinedExpr representation with internal StringLiteral field for function declaration.
Differential Revision: http://reviews.llvm.org/D5365
llvm-svn: 219393
Windows TLS relies on indexing through a tls_index in order to get at
the DLL's thread local variables. However, this index is not exported
along with the variable: it is assumed that all accesses to thread local
variables are inside the same module which created the variable in the
first place.
While there are several implementation techniques we could adopt to fix
this (notably, the Itanium ABI gets this for free), it is not worth the
heroics.
Instead, let's just ban this combination. We could revisit this in the
future if we need to.
This fixes PR21111.
llvm-svn: 219049
Richard noted in the review of r217349 that extra handling of
__builtin_assume_aligned inside of the expression evaluator was needed. He was
right, and this should address the concerns raised, namely:
1. The offset argument to __builtin_assume_aligned can have side effects, and
we need to make sure that all arguments are properly evaluated.
2. If the alignment assumption does not hold, that introduces undefined
behavior, and undefined behavior cannot appear inside a constexpr.
and hopefully the diagnostics produced are detailed enough to explain what is
going on.
llvm-svn: 218992
This CL has caused bootstrap failures on Linux and OSX buildbots running with -Werror.
Example report from http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux/builds/13183/steps/bootstrap%20clang/logs/stdio:
================================================================
[ 91%] Building CXX object tools/clang/tools/diagtool/CMakeFiles/diagtool.dir/ShowEnabledWarnings.cpp.o
In file included from /home/dtoolsbot/build/sanitizer-x86_64-linux/build/llvm/lib/Target/R600/AMDGPUISelDAGToDAG.cpp:20:
In file included from /home/dtoolsbot/build/sanitizer-x86_64-linux/build/llvm/lib/Target/R600/SIISelLowering.h:19:
/home/dtoolsbot/build/sanitizer-x86_64-linux/build/llvm/lib/Target/R600/SIInstrInfo.h:71:8: error: 'getLdStBaseRegImmOfs' overrides a member function but is not marked 'override' [-Werror,-Winconsistent-missing-override]
bool getLdStBaseRegImmOfs(MachineInstr *LdSt,
^
/home/dtoolsbot/build/sanitizer-x86_64-linux/build/llvm/include/llvm/Target/TargetInstrInfo.h:815:16: note: overridden virtual function is here
virtual bool getLdStBaseRegImmOfs(MachineInstr *LdSt,
^
================================================================
llvm-svn: 218969
for an overriding method if class has at least one
'override' specified on one of its methods.
Reviewed by Doug Gregor. rdar://18295240
(I have already checked in all llvm files with missing 'override'
methods and Bob Wilson has fixed a TableGen of FastISel so
no warnings are expected from build of llvm after this patch.
I have already verified this).
llvm-svn: 218925
This adds support for the align_value attribute. This attribute is supported by
Intel's compiler (versions 14.0+), and several of my HPC users have requested
support in Clang. It specifies an alignment assumption on the values to which a
pointer points, and is used by numerical libraries to encourage efficient
generation of vector code.
Of course, we already have an aligned attribute that can specify enhanced
alignment for a type, so why is this additional attribute important? The
problem is that if you want to specify that an input array of T is, say,
64-byte aligned, you could try this:
typedef double aligned_double attribute((aligned(64)));
void foo(aligned_double *P) {
double x = P[0]; // This is fine.
double y = P[1]; // What alignment did those doubles have again?
}
the access here to P[1] causes problems. P was specified as a pointer to type
aligned_double, and any object of type aligned_double must be 64-byte aligned.
But if P[0] is 64-byte aligned, then P[1] cannot be, and this access causes
undefined behavior. Getting round this problem requires a lot of awkward
casting and hand-unrolling of loops, all of which is bad.
With the align_value attribute, we can accomplish what we'd like in a well
defined way:
typedef double *aligned_double_ptr attribute((align_value(64)));
void foo(aligned_double_ptr P) {
double x = P[0]; // This is fine.
double y = P[1]; // This is fine too.
}
This attribute does not create a new type (and so it not part of the type
system), and so will only "propagate" through templates, auto, etc. by
optimizer deduction after inlining. This seems consistent with Intel's
implementation (thanks to Alexey for confirming the various Intel-compiler
behaviors).
As a final note, I would have chosen to call this aligned_value, not
align_value, for better naming consistency with the aligned attribute, but I
think it would be more useful to users to adopt Intel's name.
llvm-svn: 218910
Clang warns (treated as error by default, but still ignored in system headers)
when passing non-POD arguments to variadic functions, and generates a trap
instruction to crash the program if that code is ever run.
Unfortunately, MSVC happily generates code for such calls without a warning,
and there is code in system headers that use it.
This makes Clang not insert the trap instruction when in -fms-compatibility
mode, while still generating the warning/error message.
Differential Revision: http://reviews.llvm.org/D5492
llvm-svn: 218640
In addition to __builtin_assume_aligned, GCC also supports an assume_aligned
attribute which specifies the alignment (and optional offset) of a function's
return value. Here we implement support for the assume_aligned attribute by making
use of the @llvm.assume intrinsic.
llvm-svn: 218500
we were failing to find that bit-field when performing integer promotions. This
brings us closer to following the standard, and closer to GCC.
In C, this change is technically a regression: we get bit-field promotions
completely wrong in C, promoting cases that are categorically not bit-field
designators. This change makes us do so slightly more consistently, though.
llvm-svn: 218428
A record which contains a flexible array member is itself a flexible
array member. A struct which contains such a record should also
consider itself to be a flexible array member.
llvm-svn: 218378
lists. Since the fields are inititalized one at a time, using a field with
lower index to initialize a higher indexed field should not be warned on.
llvm-svn: 218339
that function, and apart from being slow, this is unnecessary: ADL can trigger
instantiations that are not permitted here. The standard isn't *completely*
clear here, but this seems like the intent, and in any case this approach is
permitted by [temp.inst]p7.
llvm-svn: 218330
warns when a guarded variable is passed by reference as a function argument.
This is released as a separate warning flag, because it could potentially
break existing code that uses thread safety analysis.
llvm-svn: 218087
The reasoning is that this construct is accepted by all compilers and valid in
C++11, so it doesn't seem like a useful warning to have enabled by default.
Building with -pedantic, -Wbind-to-temporary-copy, or -Wc++98-compat still
shows the warning.
The motivation is that I built re2, and this was the only warning that was
emitted during the build. Both changing re2 to fix the warning and detecting
clang and suppressing the warning in re2's build seem inferior than just giving
the compiler a good default for this warning.
Also move the cxx98compat version of this warning to CXX98CompatPedantic, and
update tests accordingly.
llvm-svn: 218008
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
Richard Smith