gcc's unused warnings which don't get emitted if the function is referenced even in an unevaluated context
(e.g. in templates, sizeof, etc.). Also, saying that a function is 'unused' because it won't get codegen'ed
is somewhat misleading.
- Don't emit 'unused' warnings for functions that are referenced in any part of the user's code.
- A warning that an internal function/variable won't get emitted is useful though, so introduce
-Wunneeded-internal-declaration which will warn if a function/variable with internal linkage is not
"needed" ('used' from the codegen perspective), e.g:
static void foo() { }
template <int>
void bar() {
foo();
}
test.cpp:1:13: warning: function 'foo' is not needed and will not be emitted
static void foo() { }
^
Addresses rdar://8733476.
llvm-svn: 129794
which versions of an OS provide a certain facility. For example,
void foo()
__attribute__((availability(macosx,introduced=10.2,deprecated=10.4,obsoleted=10.6)));
says that the function "foo" was introduced in 10.2, deprecated in
10.4, and completely obsoleted in 10.6. This attribute ties in with
the deployment targets (e.g., -mmacosx-version-min=10.1 specifies that
we want to deploy back to Mac OS X 10.1). There are several concrete
behaviors that this attribute enables, as illustrated with the
function foo() above:
- If we choose a deployment target >= Mac OS X 10.4, uses of "foo"
will result in a deprecation warning, as if we had placed
attribute((deprecated)) on it (but with a better diagnostic)
- If we choose a deployment target >= Mac OS X 10.6, uses of "foo"
will result in an "unavailable" warning (in C)/error (in C++), as
if we had placed attribute((unavailable)) on it
- If we choose a deployment target prior to 10.2, foo() is
weak-imported (if it is a kind of entity that can be weak
imported), as if we had placed the weak_import attribute on it.
Naturally, there can be multiple availability attributes on a
declaration, for different platforms; only the current platform
matters when checking availability attributes.
The only platforms this attribute currently works for are "ios" and
"macosx", since we already have -mxxxx-version-min flags for them and we
have experience there with macro tricks translating down to the
deprecated/unavailable/weak_import attributes. The end goal is to open
this up to other platforms, and even extension to other "platforms"
that are really libraries (say, through a #pragma clang
define_system), but that hasn't yet been designed and we may want to
shake out more issues with this narrower problem first.
Addresses <rdar://problem/6690412>.
As a drive-by bug-fix, if an entity is both deprecated and
unavailable, we only emit the "unavailable" diagnostic.
llvm-svn: 128127
use the translation unit as its declaration context, then deserialize
the actual lexical and semantic DeclContexts after the template
parameter is complete. This avoids problems when the DeclContext
itself (e.g., a class template) is dependent on the template parameter
(e.g., for the injected-class-name).
llvm-svn: 127056
DeclContext once we've created it. This mirrors what we do for
function parameters, where the parameters start out with
translation-unit context and then are adopted by the appropriate
DeclContext when it is created. Also give template parameters public
access and make sure that they don't show up for the purposes of name
lookup.
Fixes PR9400, a regression introduced by r126920, which implemented
substitution of default template arguments provided in template
template parameters (C++ core issue 150).
How on earth could the DeclContext of a template parameter affect the
handling of default template arguments?
I'm so glad you asked! The link is
Sema::getTemplateInstantiationArgs(), which determines the outer
template argument lists that correspond to a given declaration. When
we're instantiating a default template argument for a template
template parameter within the body of a template definition (not it's
instantiation, per core issue 150), we weren't getting any outer
template arguments because the context of the template template
parameter was the translation unit. Now that the context of the
template template parameter is its owning template, we get the
template arguments from the injected-class-name of the owning
template, so substitution works as it should.
llvm-svn: 127004
lead to a serious slowdown (4%) on parsing of Cocoa.h. This memory
optimization should be revisited later, when we have time to look at
the generated code.
llvm-svn: 126033
reducing the size of all declarations by one pointer. For a 64-bit
Clang parsing Cocoa.h, this saves ~630k of memory (about 3.5% of
ASTContext's memory usage for this header).
llvm-svn: 125756
LabelDecl and LabelStmt. There is a 1-1 correspondence between the
two, but this simplifies a bunch of code by itself. This is because
labels are the only place where we previously had references to random
other statements, causing grief for AST serialization and other stuff.
This does cause one regression (attr(unused) doesn't silence unused
label warnings) which I'll address next.
This does fix some minor bugs:
1. "The only valid attribute " diagnostic was capitalized.
2. Various diagnostics printed as ''labelname'' instead of 'labelname'
3. This reduces duplication of label checking between functions and blocks.
Review appreciated, particularly for the cindex and template bits.
llvm-svn: 125733
parameter packs, along with ParmVarDecl::isParameterPack(), which
looks for function parameter packs. Use these routines to fix some
obvious FIXMEs.
llvm-svn: 122904
packs, e.g.,
template<typename T, unsigned ...Dims> struct multi_array;
along with semantic analysis support for finding unexpanded non-type
template parameter packs in types, expressions, and so on.
Template instantiation involving non-type template parameter packs
probably doesn't work yet. That'll come soon.
llvm-svn: 122527
and visibility of declarations, because it was extremely messy and it
increased the size of NamedDecl.
An improved implementation is forthcoming.
llvm-svn: 121012
declarations.
The motivation for this patch is that linkage/visibility computations
are linear in the number of redeclarations of an entity, and we've run
into a case where a single translation unit has > 6500 redeclarations
of the same (unused!) external variable. Since each redeclaration
involves a linkage check, the resulting quadratic behavior makes Clang
slow to a crawl. With this change, a simple test with 512
redeclarations of a variable syntax-checks ~20x faster than
before.
That said, I hate this change, and will probably end up reverting it
in a few hours. Reasons to hate it:
- It makes NamedDecl larger, since we don't have enough free bits in
Decl to squeeze in the extra information about caching.
- There are way too many places where we need to invalidate this
cache, because the visibility of a declaration can change due to
redeclarations (!). Despite self-hosting and passing the testsuite,
I have no confidence that I've found all of places where this cache
needs to be invalidated.
llvm-svn: 120808
A new AST node is introduced:
def IndirectField : DDecl<Value>;
IndirectFields are injected into the anonymous's parent scope and chain back to
the original field. Name lookup for anonymous entities now result in an
IndirectFieldDecl instead of a FieldDecl.
There is no functionality change, the code generated should be the same.
llvm-svn: 119919
- tags with C linkage should ignore visibility=hidden
- functions and variables with explicit visibility attributes should
ignore the linkage of their types
Either of these should be sufficient to fix PR8457.
Also, FileCheck-ize a test case.
llvm-svn: 117351
its initial creation/deserialization and store the changes in a chained PCH.
The idea is that the AST entities call methods on the ASTMutationListener to give notifications
of changes; the PCHWriter implements the ASTMutationListener interface and stores the incremental changes
of the updated entity. WIP
llvm-svn: 117235
instead of deserializing the complete declaration context of the record.
Iterating over the fields of a record is very common (e.g to determine the layout), unfortunately we needlessly deserialize every declaration
that the declaration context of the record contains; this can be bad for large C++ classes that contain a lot of methods.
Fix this by allow deserialization of just the fields when we want to iterate over them.
Progress for rdar://7260160.
llvm-svn: 116507
DeclaredCopyConstructor bits in CXXRecordDecl's DefinitionData
structure. Rather than having Sema call addedConstructor or set the
bits directly at semi-random places, move all of the logic for
managing these bits into CXXRecordDecl itself and tie the
addedConstructor call into DeclContext::addDecl().
This makes it easier for AST-building clients to get the right bits
set in DefinitionData, and is one small part of <rdar://problem/8459981>.
llvm-svn: 114889
When including a PCH and later re-emitting to another PCH, the name lookup tables of DeclContexts
may be incomplete, since we now lazily deserialize the visible decls of a particular name.
Fix the issue by iterating over the un-deserialized visible decls and completing the lookup tables
of DeclContexts before writing them out.
llvm-svn: 111698
*Huge* improvement over the amount of deserializing that we do for C++ lookup.
e.g, if he have the Carbon header precompiled and include it on a file containing this:
int x;
these are the before/after stats:
BEFORE:
*** AST File Statistics:
578 stat cache hits
4 stat cache misses
548/30654 source location entries read (1.787695%)
15907/16501 types read (96.400223%)
53525/59955 declarations read (89.275291%)
33993/43525 identifiers read (78.099945%)
41516/51891 statements read (80.006165%)
77/5317 macros read (1.448185%)
0/6335 lexical declcontexts read (0.000000%)
1/5424 visible declcontexts read (0.018437%)
AFTER using the on-disk table:
*** AST File Statistics:
578 stat cache hits
4 stat cache misses
548/30654 source location entries read (1.787695%)
10/16501 types read (0.060602%)
9/59955 declarations read (0.015011%)
161/43525 identifiers read (0.369902%)
20/51891 statements read (0.038542%)
6/5317 macros read (0.112846%)
0/6335 lexical declcontexts read (0.000000%)
2/5424 visible declcontexts read (0.036873%)
There's only one issue affecting mostly the precompiled preambles which I will address soon.
llvm-svn: 111636
Now all classes derived from Attr are generated from TableGen.
Additionally, Attr* is no longer its own linked list; SmallVectors or
Attr* are used. The accompanying LLVM commit contains the updates to
TableGen necessary for this.
Some other notes about newly-generated attribute classes:
- The constructor arguments are a SourceLocation and a Context&,
followed by the attributes arguments in the order that they were
defined in Attr.td
- Every argument in Attr.td has an appropriate accessor named getFoo,
and there are sometimes a few extra ones (such as to get the length
of a variadic argument).
Additionally, specific_attr_iterator has been introduced, which will
iterate over an AttrVec, but only over attributes of a certain type. It
can be accessed through either Decl::specific_attr_begin/end or
the global functions of the same name.
llvm-svn: 111455
to the consumer until the DeclContext is fully prepared.
Before, due to recursive loading, we could be in a situation where we would try to deserialize the decls of a DeclContext which was already doing that, and bad things would happen. In the specific case I encountered, the lexical decls would
form a cycle and we would enter infinite loop territory.
llvm-svn: 109857
- Stop reading in (and thus deserializing) every declaration in the TU when creating a dependent PCH.
- Switch the storage of a decl context's lexical declarations to a blob containing the IDs instead of a record. This is the only sane way of supporting update records later on.
llvm-svn: 109474
This has 2 (slight) advantages:
-Make explicit at getBody()'s callsite that we expect/handle only CompoundStmt and not CXXTryStmt.
-Better tracking of Decl::getBody()'s callsites.
llvm-svn: 107771
Douglas Gregor