CheckLValueConstantExpression.
Richard pointed out that using the address of a TLS variable is ok in a
core C++11 constant expression, as long as it isn't part of the eventual
result of constant expression evaluation. Having the check in
CheckLValueConstantExpression accomplishes this.
llvm-svn: 162850
This warns in two specific situations:
1) For potentially swapped function arguments, e.g.
void foo(bool, float);
foo(1.7, false);
2) Misplaced brackets around function call arguments, e.g.
bool InRange = fabs(a - b < delta);
Where the last argument in a function call is implicitly converted
from bool to float, and the function returns a float which gets
implicitly converted to bool.
Patch by Andreas Eckleder!
llvm-svn: 162763
The old error message stating that 'begin' was an undeclared identifier
is replaced with a new message explaining that the error is in the range
expression, along with which of the begin() and end() functions was
problematic if relevant.
Additionally, if the range was a pointer type or defines operator*,
attempt to dereference the range, and offer a FixIt if the modified range
works.
llvm-svn: 162248
nested names as id-expressions, using the annot_primary_expr annotation, where
possible. This removes some redundant lookups, and also allows us to
typo-correct within tentative parsing, and to carry on disambiguating past an
identifier which we can determine will fail lookup as both a type and as a
non-type, allowing us to disambiguate more declarations (and thus offer
improved error recovery for such cases).
This also introduces to the parser the notion of a tentatively-declared name,
which is an identifier which we *might* have seen a declaration for in a
tentative parse (but only if we end up disambiguating the tokens as a
declaration). This is necessary to correctly disambiguate cases where a
variable is used within its own initializer.
llvm-svn: 162159
This is effectively a warning for code that violates core issue 903 & thus will
become standard error in the future, hopefully. It catches strange null
pointers such as: '\0', 1 - 1, const int null = 0; etc...
There's currently a flaw in this warning (& the warning for 'false' as a null
pointer literal as well) where it doesn't trigger on comparisons (ptr == '\0'
for example). Fix to come in a future patch.
Also, due to this only being a warning, not an error, it triggers quite
frequently on gtest code which tests expressions for null-pointer-ness in a
SFINAE context (so it wouldn't be a problem if this was an error as in an
actual implementation of core issue 903). To workaround this for now, the
diagnostic does not fire in unevaluated contexts.
Review by Sean Silva and Richard Smith.
llvm-svn: 161501
A conditional operator between glvalues of types cv1 T and cv2 T produces a
glvalue if the expressions are of the same value kind and one of cv1 and cv2
is a subset of the other.
A conditional operator between two null pointer constants is permitted if one
of them is of type std::nullptr_t.
llvm-svn: 161476
and the other is a glvalue of class type, don't forget to copy-initialize a
temporary when performing the lvalue-to-rvalue conversion on the glvalue.
Strangely, DefaultLvalueConversions misses this part of the lvalue-to-rvalue
conversions.
llvm-svn: 161450
for side-effects. Instead, check for side-effects after performing
initialization. Doing so also removes some strange corner cases and differences
between in-class initialization and constructor initialization.
llvm-svn: 161449
in duplicate -Wuninitialized warnings. Change so that only the check in
TryConstructorInitialization() will be used and a single warning be emitted.
llvm-svn: 161345
accurate by asking the parser whether there was an ambiguity rather than trying
to reverse-engineer it from the DeclSpec. Make the with-parameters case have
better diagnostics by using semantic information to drive the warning,
improving the diagnostics and adding a fixit.
Patch by Nikola Smiljanic. Some minor changes by me to suppress diagnostics for
declarations of the form 'T (*x)(...)', which seem to have a very high false
positive rate, and to reduce indentation in 'warnAboutAmbiguousFunction'.
llvm-svn: 160998
When performing the simplistic overload resolution for single-argument methods,
don't check the best overload for ambiguity with itself when the best overload
doesn't happen to be the first one.
Fixes PR13480.
llvm-svn: 160961
expressions to have complete return types (or accessible destructors). If the
return type is required to be complete for some other reason (for instance, if
it is needed by overload resolution), then it will still be required to be
complete. This is apparently required in order to parse a MSVC11 header.
llvm-svn: 160924
a defaulted special member function until the exception specification is needed
(using the same criteria used for the delayed instantiation of exception
specifications for function temploids).
EST_Delayed is now EST_Unevaluated (using 1330's terminology), and, like
EST_Uninstantiated, carries a pointer to the FunctionDecl which will be used to
resolve the exception specification.
This is enabled for all C++ modes: it's a little faster in the case where the
exception specification isn't used, allows our C++11-in-C++98 extensions to
work, and is still correct for C++98, since in that mode the computation of the
exception specification can't fail.
The diagnostics here aren't great (in particular, we should include implicit
evaluation of exception specifications for defaulted special members in the
template instantiation backtraces), but they're not much worse than before.
Our approach to the problem of cycles between in-class initializers and the
exception specification for a defaulted default constructor is modified a
little by this change -- we now reject any odr-use of a defaulted default
constructor if that constructor uses an in-class initializer and the use is in
an in-class initialzer which is declared lexically earlier. This is a closer
approximation to the current draft solution in core issue 1351, but isn't an
exact match (but the current draft wording isn't reasonable, so that's to be
expected).
llvm-svn: 160847
Rather than adding a ContainsUnexpandedParameterPack bit to essentially every
AST node, we tunnel the bit directly up to the surrounding lambda expression
when we reach a context where an unexpanded pack can not normally appear.
Thus any statement or declaration within a lambda can now potentially contain
an unexpanded parameter pack.
llvm-svn: 160705
A warning was added in r150128 for returning non-C compatible
user-defined types from functions with C linkage.
This makes the text more clear for the case when the type isn't
decidedly non-C compatible, but incomplete.
llvm-svn: 160681
In Microsoft mode, we emit a warning instead of an error.
This fixes a couple of errors when parsing the MSVC 11 RC headers with clang.
llvm-svn: 160613
While we still want to consider this a hard error (non-POD variadic args are
normally a DefaultError warning), delaying the diagnostic allows us to give
better error messages, which also match the usual non-POD errors more closely.
In addition, this change improves the diagnostic messages for format string
argument type mismatches by passing down the type of the callee, so we can
say "variadic method" or "variadic function" appropriately.
<rdar://problem/11825593>
llvm-svn: 160517
use out of TransferFunctions, and compute it in advance rather than on-the-fly.
This allows us to handle compound assignments with DeclRefExprs on the RHS
correctly, and also makes it trivial to treat const& function parameters as not
initializing the argument. The patch also makes both of those changes.
llvm-svn: 160330
Hans Wennborg