Split out a new ExpressionEvaluationContext flag for this case, and don't treat
it as unevaluated in C++11. This fixes some crash-on-invalids where we would
allow references to class members in potentially-evaluated constant expressions
in static member functions, and also fixes half of PR10177.
The fix to PR10177 exposed a case where template instantiation failed to provide
a source location for a diagnostic, so TreeTransform has been tweaked to supply
source locations when transforming a type. The source location is still not very
good, but MarkDeclarationsReferencedInType would need to operate on a TypeLoc to
improve it further.
Also fix MarkDeclarationReferenced in C++98 mode to trigger instantiation for
static data members of class templates which are used in constant expressions.
This fixes a link-time problem, but we still incorrectly treat the member as
non-constant. The rest of the fix for that issue is blocked on PCH support for
early-instantiated static data members, which will be added in a subsequent
patch.
llvm-svn: 146955
variable is initialized by a non-constant expression, and pass in the variable
being declared so that earlier-initialized fields' values can be used.
Rearrange VarDecl init evaluation to make this possible, and in so doing fix a
long-standing issue in our C++ constant expression handling, where we would
mishandle cases like:
extern const int a;
const int n = a;
const int a = 5;
int arr[n];
Here, n is not initialized by a constant expression, so can't be used in an ICE,
even though the initialization expression would be an ICE if it appeared later
in the TU. This requires computing whether the initializer is an ICE eagerly,
and saving that information in PCH files.
llvm-svn: 146856
floating literal value does not fit into the destination type. Such casts have
undefined behavior at translation time; treating them as non-ICE matches the
behavior of modern gcc versions.
llvm-svn: 146842
fails within a call to a constexpr function. Add -fconstexpr-backtrace-limit
argument to driver and frontend, to control the maximum number of notes so
produced (default 10). Fix APValue printing to be able to pretty-print all
APValue types, and move the testing for this functionality from a unittest to
a -verify test now that it's visible in clang's output.
llvm-svn: 146749
diagnostic message are compared. If either is a substring of the other, then
no error is given. This gives rise to an unexpected case:
// expect-error{{candidate function has different number of parameters}}
will match the following error messages from Clang:
candidate function has different number of parameters (expected 1 but has 2)
candidate function has different number of parameters
It will also match these other error messages:
candidate function
function has different number of parameters
number of parameters
This patch will change so that the verification string must be a substring of
the diagnostic message before accepting. Also, all the failing tests from this
change have been corrected. Some stats from this cleanup:
87 - removed extra spaces around verification strings
70 - wording updates to diagnostics
40 - extra leading or trailing characters (typos, unmatched parens or quotes)
35 - diagnostic level was included (error:, warning:, or note:)
18 - flag name put in the warning (-Wprotocol)
llvm-svn: 146619
The motivation here is a "clever" implementation of strncmp(), which peels the first few comparisons via chained conditional expressions which ensure that the input arrays are known at compile time to be sufficiently large.
llvm-svn: 146430
whether an expression is a (core) constant expression as a side-effect of
evaluation. This takes us from accepting far too few expressions as ICEs to
accepting slightly too many -- fixes for the remaining cases are coming next.
The diagnostics produced when an expression is found to be non-constant are
currently quite poor (with generic wording but reasonable source locations),
and will be improved in subsequent commits.
llvm-svn: 146289
methods) to bool. E.g.
void foo() {}
if (f) { ... // <- Warns here.
}
Only applies to non-weak functions, and does not apply if the function address
is taken explicitly with the addr-of operator.
llvm-svn: 145849
explicit template specializations (which represent actual functions somebody wrote).
Along the way, refactor some other code which similarly cares about whether or
not they are looking at a template instantiation.
llvm-svn: 145547
declaration at namespace scope is followed by a semicolon and an open-brace
(or in C++, a 'try', ':' or '='), then the error is probably a function
definition with a spurious ';', rather than a mysterious '{'.
llvm-svn: 145372
This supports single-element initializer lists for references according to DR1288, as well as creating temporaries and binding to them for other initializer lists.
llvm-svn: 145186
pointer mismatch. Cases covered are: initialization, assignment, and function
arguments. Additional text will give the extra information about the nature
of the mismatch: different classes for member functions, wrong number of
parameters, different parameter type, different return type, and function
qualifier mismatch.
llvm-svn: 145114
semantics and defaults as the corresponding g++ arguments. The historical g++
argument -ftemplate-depth-N is kept for compatibility, but modern g++ versions
no longer document that option.
Add -cc1 argument -fconstexpr-depth N to implement the corresponding
functionality.
The -ftemplate-depth=N part of this fixes PR9890.
llvm-svn: 145045
lifetimes have been extended via reference binding. The type of the
reference and the type of the temporary are not necessarily the same,
which could cause a crash. Fixes <rdar://problem/10398199>.
llvm-svn: 144646
or MemberExpr which refers to it. As a side-effect, MemberExprs which refer to
static member functions and static data members are now emitted as constant
expressions.
llvm-svn: 144468
to disable the corresponding -Wc++98-compat warnings in addition to the C++11
extension warnings, so that people already using these flags can switch to C++11
mode and turn on -Wc++98-compat.
llvm-svn: 144404
reinstates r144273; a combination of r144333's fix for NoOp rvalue-to-lvalue
casts and some corresponding changes here resolve the regression which that
caused.
This patch also adds support for some additional forms of member function call,
along with additional testing.
llvm-svn: 144369
expression evaluation:
- When folding a non-value-dependent expression, we may try to use the
initializer of a value-dependent variable. If that happens, give up.
- In C++98, actually check that a const, non-volatile DeclRefExpr inside an ICE
is of integral or enumeration type (a reference isn't OK!)
- In C++11, DeclRefExprs for objects of const literal type initialized with
value-dependent expressions are themselves value-dependent.
- So are references initialized with value-dependent expressions (though this
case is missing from the C++11 standard, along with many others).
llvm-svn: 144056
partially undoes the revert in r143491, but does not introduce any new instances
of the underlying issue (which is not yet fixed) in code which does not use
the 'constexpr' keyword.
llvm-svn: 143905
to allow us to implement the C++11 rule that a non-active union member can't be
read, and use it to implement subobject access for string literals.
llvm-svn: 143677
definition, we may not have a scope corresponding to the namespace
where that friend function template actually lives. Work around this
issue by faking up a scope with the appropriate DeclContext.
This is a bit of a hack, but it fixes <rdar://problem/10204947>.
llvm-svn: 143614
wrong class, make sure to drop it immediately; we don't want that
constructor to be available within the DeclContext. Fixes
<rdar://problem/9677163>.
llvm-svn: 143506
just integers and floating point types. Since we don't support evaluating class
types or performing lvalue-to-rvalue conversions on array elements yet, this
just means pointer types right now.
llvm-svn: 143298
Track the function invocation where an lvalue referring to a constexpr function
parameter originated from, and use it to substitute the correct argument and to
determine whether such an argument's lifetime has ended.
llvm-svn: 143296
constexpr function arguments outside of their function (passing or returning
them by reference) does not work correctly yet.
Calling constexpr function templates does not work yet, since the bodies are not
instantiated until the end of the translation unit.
llvm-svn: 143234
are present in all the necessary places:
In constant expression evaluation, evaluate lvalues as lvalues and rvalues as
rvalues. Remove special case for caching reference initialization and fix a
cyclic initialization crash in the process.
llvm-svn: 143204
rvalue. An assertion to catch this is in ImpCastExprToType will follow, but
vector operations currently trip over this (due to omitting the usual arithmetic
conversions). Also add an assert to catch missing lvalue-to-rvalue conversions
on the LHS of ->.
llvm-svn: 143155
rvalues, as C++11 constant evaluation semantics require. DeclRefs referring to
references can now use the normal initialization-caching codepath, which
incidentally fixes a crash in cyclic initialization of references.
llvm-svn: 142844
but trivially constructible and destructible variables in C++11 mode. Also
incidentally improve the precision of the wording for jump diagnostics in C++98
mode.
llvm-svn: 142619
the right namespace in C++11 mode. Teach the code to prefer the 'must be in
precisely this namespace' diagnostic whenever that's true, and fix a defect
which resulted in the -Wc++11-compat warning in C++98 mode sometimes being
omitted.
llvm-svn: 142329
This also applies to C99-style aggregate literals, should they be used in C++11, since they are effectively identical to constructor call list-initialization syntax.
llvm-svn: 142147
This also adds a -Wc++98-compat-pedantic for warning on constructs which would
be diagnosed by -std=c++98 -pedantic (that is, it warns even on C++11 features
which we enable by default, with no warning, in C++98 mode).
llvm-svn: 142034
through varargs. This only happens when we're in an unevaluated
context, where we don't want to trigger an error anyway. Fixes PR11131
/ <rdar://problem/10288375>.
llvm-svn: 141986
If the code file is not run through the preproccessor to remove comments,
then FileCheck will match the strings within the CHECK commands rendering
the test useless.
llvm-svn: 141911
C++11 mode but keep their sources compatible with C++98. This patch implements
the -Wc++98-compat-variadic-templates sub-flag and -Wc++98-compat to include
it.
llvm-svn: 141898
We'd also like for "C++11" or "c++11" to be used for the warning
groups, but without removing the old warning flags. Patches welcome;
I've run out of time to work on this today.
llvm-svn: 141801
and DefaultFunctionArrayLvalueConversion. To prevent
significant regression for should-this-be-a-call fixits,
and to repair some such regression from the introduction of
bound member placeholders, make those placeholder checks
try to build calls appropriately. Harden the build-a-call
logic while we're at it.
llvm-svn: 141738
The main motivation was to do typo correction in C++ "new" statements,
though picking it up in other places where type names are expected was
pretty much a freebie.
llvm-svn: 141621
function type' when that expression is actually an overloaded function
reference (and not the address of an overloaded function
reference). Fixes PR11066.
llvm-svn: 141514
We had an extension which allowed const static class members of floating-point type to have in-class initializers, 'as a C++0x extension'. However, C++0x does not allow this. The extension has been kept, and extended to all literal types in C++0x mode (with a fixit to add the 'constexpr' specifier).
llvm-svn: 140801
the information on to Sema. There's still an incorrectness in the way template instantiation
works now, but that is due to a far larger underlying representational problem.
Also add a test case for various list initialization cases of scalars, which test this
commit as well as the previous one.
llvm-svn: 140460
This fixes a few errors when parsing MFC code with clang.
BTW clang trunk is now about 5 patches away to be able the parse the default wizard-generated MFC project.
llvm-svn: 140452
is cast to a boolean. An exception has been made for string literals in
logical expressions to allow the common case of use in assert statements.
bool x;
x = "hi"; // Warn here
void foo(bool x);
foo("hi"); // Warn here
assert(0 && "error");
assert("error); // Warn here
llvm-svn: 140405
the key function is inline, rather than the original
declaration. Perhaps FunctionDecl::isInlined() is poorly named. Fixes
<rdar://problem/9979458>.
llvm-svn: 140400
presence of an implicit move assignment operator. I think the implicit
copy assignment operator case was also wrong, but just in a "displaying
the wrong diagnostic" way.
llvm-svn: 140139
of false positive warnings that depend on noreturn destructors pruning
the CFGs, but only in C++0x mode!
This was really surprising as the debugger quickly reveals that the
attributes are parsed correctly (and using the same code) in both modes.
The warning fires in the same way in both modes. But between parsing and
building the destructor declaration with the noreturn attribute and the
warning, it magically disappears. The key? The 'noexcept' appears!
When we were rebuilding the destructor type with the computed implicit
noexcept we completely dropped the old type on the floor. This almost
makes sense (as the arguments and return type to a destructor aren't
exactly unpredictable), but lost any function type attributes as well.
The fix is simple, we build the new type off of the old one rather than
starting fresh.
Testing this is a bit awkward. I've done it by running the
noreturn-sensitive tests in both modes, which previous failed and now
passes, but if anyone has ideas about how to more specifically and
thoroughly test that the extended info on a destructor is preserved when
adding noexcept, I'm all ears.
llvm-svn: 140138
We were failing to set source locations and ranges in isUnusedResultAWarning
for CXXOperatorCallExprs, leading to an "expression result unused" warning
with absolutely no context if the expression was inside a macro.
llvm-svn: 140036
For example:
void f(float);
void f(int);
int main {
long a;
f(a);
}
Here, MSVC will call f(int) instead of generating a compile error as clang will do in standard mode.
This fixes a few errors when parsing MFC code with clang.
llvm-svn: 140007
temporary objects and local variables. When detected, these split the
block, marking the new one as having only the exit block as a successor.
This prevents a large number of false positives in warnings sensitive to
no-return constructs such as -Wreturn-type, and fixes the remainder of
PR10063 along with several variations of this bug that had not been
reported. The test cases are extended across the board to cover these
patterns.
This also checks in a stress test for these types of CFGs. The stress
test declares some 32k variables, a mixture of no-return and normal
destructors. Previously, this resulted in roughly 2500 CFG blocks, but
didn't model any of the no-return destructors. With this patch, it
results in over 33k blocks, many of them now unreachable.
The nice thing about how the analyzer is set up? This causes *no*
regression in performance of building the CFG. It actually in some cases
makes it faster, as best I can benchmark. The analysis for -Wreturn-type
(and any other that cares about no-return code paths) is technically
slower now as it has to look at many more candidate blocks, but it
computes the correct answer. I have more test cases to follow, I think
they all work now. Also I have further work that should dramatically
simplify analyses in the presence of no-return.
llvm-svn: 139586
and case statements. Use this to make the logic in the CFG builder more
robust at finding the actual statements within a compound statement,
even when there are many layers of labels obscuring it.
Also extend the test cases for a large chunk of PR10063. Still more work
to do here though.
llvm-svn: 139437
ctor-initializer, remember to call the Sema action to generate default
ctor-initializers. What a delightful little miscompile. Fixes PR10578
/ <rdar://problem/9877267>.
llvm-svn: 139253
well.
Also, clean up the flow of the code a bit, and factor things more
nicely.
Finally, add the test case that was missing from my previous
commit (sorry), with new tests added to cover temporaries and other fun
cases.
llvm-svn: 139077
of the function in question when applicable (that is, not for blocks).
Patch by Joerg Sonnenberger with some stylistic tweaks by me.
When discussing this weth Joerg, streaming the decl directly into the
diagnostic didn't work because we have a pointer-to-const, and the
overload doesn't accept such. In order to make my style tweaks to the
patch, I first changed the overload to accept a pointer-to-const, and
then changed the diagnostic printing layer to also use
a pointer-to-const, cleaning up a gross line of code along the way.
llvm-svn: 138854
collision between C99 hexfloats and C++0x user-defined literals by
giving C99 hexfloats precedence. Also, warning about user-defined
literals that conflict with hexfloats and those that have names that
are reserved by the implementation. Fixes <rdar://problem/9940194>.
llvm-svn: 138839
This makes the code duplication of implicit special member handling even worse,
but the cleanup will have to come later. For now, this works.
Follow-up with tests for explicit defaulting and enabling the __has_feature
flag to come.
llvm-svn: 138821
system flags an error when unlocking a lock which was not held, locking
the same lock twice, having a different lockset on each iteration of a
loop, or going out of scope while still holding a lock. In order to
successfully use the lockset, this patch also makes sure that attribute
arguments are attached correctly for later parsing.
This patch was also worked on by DeLesley Hutchins.
Note: This patch has been reviewed by Chandler Carruth and Jeffrey
Yasskin. Feel free to provide post-commit review comments for a
subsequent patch.
llvm-svn: 138350
For the test case added to function-redecl.cpp, we were previously complaining
about a mismatch in the parameter types, since the definition used the
typedef'd type.
llvm-svn: 138318
const int &x = x;
This crashed by inifinetly recursing within the lvalue evaluation
routine. I've added a (somewhat) braindead way of preventing this
recursion. If folks have better suggestions for how to avoid it I'm all
ears.
That said, we have some work to do. This doesn't trigger a single
warning for uninitialized, self-initialized or otherwise completely
wrong code. In some senses, the crash was almost better.
llvm-svn: 138239
even when overloaded and user-defined. These operators are both more
valuable to warn on (due to likely typos) and extremely unlikely to be
reasonable for use to trigger side-effects.
llvm-svn: 137823
-Wunused was a mistake. It resulted in duplicate warnings and lots of
other hacks. Instead, this should be a special sub-category to
-Wunused-value, much like -Wunused-result is.
Moved to -Wunused-comparison, moved the implementation to piggy back on
the -Wunused-value implementation instead of rolling its own, different
mechanism for catching all of the "interesting" statements.
I like the unused-value mechanism for this better, but its currently
missing several top-level statements. For now, I've FIXME-ed out those
test cases. I'll enhance the generic infrastructure to catch these
statements in a subsequent patch.
This patch also removes the cast-to-void fixit hint. This hint isn't
available on any of the other -Wunused-value diagnostics, and if we want
it to be, we should add it generically rather than in one specific case.
llvm-svn: 137822
code is very likely to be buggy, but its going to require more
significant changes on the part of the user to correct it in this case.
llvm-svn: 137820
a complement to the warnings we provide in condition expressions. Much
like we warn on conditions such as:
int x, y;
...
if (x = y) ... // Almost always a typo of '=='
This warning applies the complementary logic to "top-level" statements,
or statements whose value is not consumed or used in some way:
int x, y;
...
x == y; // Almost always a type for '='
We also mirror the '!=' vs. '|=' logic.
The warning is designed to fire even for overloaded operators for two reasons:
1) Especially in the presence of widespread templates that assume
operator== and operator!= perform the expected comparison operations,
it seems unreasonable to suppress warnings on the offchance that
a user has written a class that abuses these operators, embedding
side-effects or other magic within them.
2) There is a trivial source modification to silence the warning for
truly exceptional cases:
(void)(x == y); // No warning
A (greatly reduced) form of this warning has already caught a number of
bugs in our codebase, so there is precedent for it actually firing. That
said, its currently off by default, but enabled under -Wall.
There are several fixmes left here that I'm working on in follow-up
patches, including de-duplicating warnings from -Wunused, sharing code
with -Wunused's implementation (and creating a nice place to hook
diagnostics on "top-level" statements), and handling cases where a proxy
object with a bool conversion is returned, hiding the operation in the
cleanup AST nodes.
Suggestions for any of this code more than welcome. Also, I'd really
love suggestions for better naming than "top-level".
llvm-svn: 137819
Old warning:
warning: use of NULL in arithmetic operation [-Wnull-arithmetic]
return 10 <= NULL;
^ ~~~~
New warning:
warning: comparison between NULL and non-pointer ('int' and NULL) [-Wnull-arithmetic]
return 10 <= NULL;
~~ ^ ~~~~
llvm-svn: 137377
Sebastian Redl