In Parser::ParseUsingDeclaration(...) when we call ParseEnumSpecifier(...) it is
not calling SetTypeSpecError() on DS when it detects an error. That means that
DS is left set to TST_unspecified. When we then pass DS into
Sema::ActOnUsingEnumDeclaration(...) we hit an llvm_unreachable(...) since it
expects it to be one of three states TST_error, TST_enum or TST_typename.
This fixes https://github.com/llvm/llvm-project/issues/57347
Differential Revision: https://reviews.llvm.org/D132695
C89 allowed a type specifier to be elided with the resulting type being
int, aka implicit int behavior. This feature was subsequently removed
in C99 without a deprecation period, so implementations continued to
support the feature. Now, as with implicit function declarations, is a
good time to reevaluate the need for this support.
This patch allows -Wimplicit-int to issue warnings in C89 mode (off by
default), defaults the warning to an error in C99 through C17, and
disables support for the feature entirely in C2x. It also removes a
warning about missing declaration specifiers that really was just an
implicit int warning in disguise and other minor related cleanups.
More generally, this permits a template to be specialized in any scope in which
it could be defined, so this also supersedes DR44 and DR374 (the latter of
which we previously only implemented in C++11 mode onwards due to unclarity as
to whether it was a DR).
llvm-svn: 327705
The heuristic that we use here is:
* the left-hand side must be a simple identifier or a class member access
* the right-hand side must be '<' followed by either a '>' or by a type-id that
cannot be an expression (in particular, not followed by '(' or '{')
* there is a '>' token matching the '<' token
The second condition guarantees the expression would otherwise be ill-formed.
If we're confident that the user intended the name before the '<' to be
interpreted as a template, diagnose the fact that we didn't interpret it
that way, rather than diagnosing that the template arguments are not valid
expressions.
llvm-svn: 302615
It's actually meaningful and useful to allow such variables to have no
initializer, but we are strictly following the standard here until the C++
committee reaches consensus on allowing this.
llvm-svn: 294785
explicit specialization to a warning for C++98 mode (this is a defect report
resolution, so per our informal policy it should apply in C++98), and turn
the warning on by default for C++11 and later. In all cases where it fires, the
right thing to do is to remove the pointless explicit instantiation.
llvm-svn: 280308
It is only a crash if the compiler optimize for this!=nullptr because
LocalInstantiationScope::getPartiallySubstitutedPack checks if 'this' is null
(This is crashing when clang is compiled with GCC6)
Differential Revision: http://reviews.llvm.org/D20511
llvm-svn: 270845
particular don't assume that two declarations of the same kind in the same
context are declaring the same entity. That's not true when the same name is
declared multiple times as internal-linkage symbols within a module.
(getCanonicalDecl is cheap now, so we can just use it here.)
llvm-svn: 251898
We referred to all declaration in definitions in our diagnostic messages
which is can be inaccurate. Instead, classify the declaration and emit
an appropriate diagnostic for the new declaration and an appropriate
note pointing to the old one.
This fixes PR24116.
llvm-svn: 242190
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
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