"used" (e.g., we will refer to the vtable in the generated code) and
when they are defined (i.e., because we've seen the key function
definition). Previously, we were effectively tracking "potential
definitions" rather than uses, so we were a bit too eager about emitting
vtables for classes without key functions.
The new scheme:
- For every use of a vtable, Sema calls MarkVTableUsed() to indicate
the use. For example, this occurs when calling a virtual member
function of the class, defining a constructor of that class type,
dynamic_cast'ing from that type to a derived class, casting
to/through a virtual base class, etc.
- For every definition of a vtable, Sema calls MarkVTableUsed() to
indicate the definition. This happens at the end of the translation
unit for classes whose key function has been defined (so we can
delay computation of the key function; see PR6564), and will also
occur with explicit template instantiation definitions.
- For every vtable defined/used, we mark all of the virtual member
functions of that vtable as defined/used, unless we know that the key
function is in another translation unit. This instantiates virtual
member functions when needed.
- At the end of the translation unit, Sema tells CodeGen (via the
ASTConsumer) which vtables must be defined (CodeGen will define
them) and which may be used (for which CodeGen will define the
vtables lazily).
From a language perspective, both the old and the new schemes are
permissible: we're allowed to instantiate virtual member functions
whenever we want per the standard. However, all other C++ compilers
were more lazy than we were, and our eagerness was both a performance
issue (we instantiated too much) and a portability problem (we broke
Boost test cases, which now pass).
Notes:
(1) There's a ton of churn in the tests, because the order in which
vtables get emitted to IR has changed. I've tried to isolate some of
the larger tests from these issues.
(2) Some diagnostics related to
implicitly-instantiated/implicitly-defined virtual member functions
have moved to the point of first use/definition. It's better this
way.
(3) I could use a review of the places where we MarkVTableUsed, to
see if I missed any place where the language effectively requires a
vtable.
Fixes PR7114 and PR6564.
llvm-svn: 103718
particular, don't complain about unused variables that have dependent
type until instantiation time, so that we can look at the type of the
variable. Moreover, only complain about unused variables that have
neither a user-declared constructor nor a non-trivial destructor.
llvm-svn: 103362
typedef int functype(int, int);
functype func;
also instantiate the synthesized function parameters for the resulting
function declaration.
With this change, Boost.Wave builds and passes all of its regression
tests.
llvm-svn: 103025
(-Wunused-exception-parameter) than normal variables, since it's more
common to name and then ignore an exception parameter. This warning is
neither enabled by default nor by -Wall. Fixes <rdar://problem/7931045>.
llvm-svn: 102931
entering the current instantiation. Set up a little to preserve type location
information for typename types while we're in there.
Fixes a Boost failure.
llvm-svn: 102673
when they are not complete (since we could not match them up to
anything) and ensuring that enum parsing can cope with dependent
elaborated-type-specifiers. Fixes PR6915 and PR6649.
llvm-svn: 102247
(e.g., no typename, enum, class, etc.), e.g., because the context is
one that is known to refer to a type. Patch from Enea Zaffanella!
llvm-svn: 102243
arguments. Rather than having the parser call ActOnParamDeclarator
(which is a bit of a hack), call a new ActOnObjCExceptionDecl
action. We'll be moving more functionality into this handler to
perform earlier checking of @catch.
llvm-svn: 102222
way that C does. Among other differences, elaborated type specifiers
are defined to skip "non-types", which, as you might imagine, does not
include typedefs. Rework our use of IDNS masks to capture the semantics
of different kinds of declarations better, and remove most current lookup
filters. Removing the last remaining filter is more complicated and will
happen in a separate patch.
Fixes PR 6885 as well some spectrum of unfiled bugs.
llvm-svn: 102164
function declaration, since it may end up being changed (e.g.,
"extern" can become "static" if a prior declaration was static). Patch
by Enea Zaffanella and Paolo Bolzoni.
llvm-svn: 101826
in case it ends up doing something that might trigger diagnostics
(template instantiation, ambiguity reporting, access
reporting). Noticed while working on PR6831.
llvm-svn: 101412
ASTContext::getTypeSize() rather than ASTContext::getIntWidth() for
the width of an integral type. The former includes padding for bools
(to the target's size) while the latter does not, so we woud end up
zero-extending bools to the target width when we shouldn't. Fixes a
crash-on-valid in the included test.
llvm-svn: 101372
generally recover from typos in keywords (since we would effectively
have to mangle the token stream). However, there are still benefits to
typo-correcting with keywords:
- We don't make stupid suggestions when the user typed something
that is similar to a keyword.
- We can suggest the keyword in a diagnostic (did you mean
"static_cast"?), even if we can't recover and therefore don't have
a fix-it.
llvm-svn: 101274
function's type is (strictly speaking) non-dependent. This ensures
that, e.g., default function arguments get instantiated properly.
And, since I couldn't resist, collapse the two implementations of
function-parameter instantiation into calls to a single, new function
(Sema::SubstParmVarDecl), since the two had nearly identical code (and
each had bugs the other didn't!). More importantly, factored out the
semantic analysis of a parameter declaration into
Sema::CheckParameter, which is called both by
Sema::ActOnParamDeclarator (when parameters are parsed) and when a
parameter is instantiated. Previously, we were missing some
Objective-C and address-space checks on instantiated function
parameters.
Fixes PR6733.
llvm-svn: 101029
