- If a declaration is an invalid redeclaration of an existing name,
complain about the invalid redeclaration then avoid adding it to
the AST (we can still parse the definition or initializer, if any).
- If the declaration is invalid but there is no prior declaration
with that name, introduce the invalid declaration into the AST
(for later error recovery).
- If the declaration is an invalid redeclaration of a builtin that
starts with __builtin_, we produce an error and drop the
redeclaration. If it is an invalid redeclaration of a library
builtin (e.g., malloc, printf), warn (don't error!) and drop the
redeclaration.
If a user attempts to define a builtin, produce an error and (if it's
a library builtin like malloc) suggest -ffreestanding.
This addresses <rdar://problem/6097585> and PR2892. However, PR3588 is
still going to cause some problems when builtins are redeclared
without a prototype.
llvm-svn: 64639
DiagnoseUseOfDeprecatedDecl method. This ensures that they
are treated consistently. This gets us 'unavailable' support
on a few new types of decls, and makes sure we consistently
silence deprecated when the caller is also deprecated.
llvm-svn: 64612
about, whether they are builtins or not. Use this to add the
appropriate "format" attribute to NSLog, NSLogv, asprintf, and
vasprintf, and to translate builtin attributes (from Builtins.def)
into actual attributes on the function declaration.
Use the "printf" format attribute on function declarations to
determine whether we should do format string checking, rather than
looking at an ad hoc list of builtins and "known" function names.
Be a bit more careful about when we consider a function a "builtin" in
C++.
llvm-svn: 64561
we can define builtins such as fprintf, vfprintf, and
__builtin___fprintf_chk. Give a nice error message when we need to
implicitly declare a function like fprintf.
llvm-svn: 64526
printf-like functions, both builtin functions and those in the
C library. The function-call checker now queries this attribute do
determine if we have a printf-like function, rather than scanning
through the list of "known functions IDs". However, there are 5
functions they are not yet "builtins", so the function-call checker
handles them specifically still:
- fprintf and vfprintf: the builtins mechanism cannot (yet)
express FILE* arguments, so these can't be encoded.
- NSLog: the builtins mechanism cannot (yet) express NSString*
arguments, so this (and NSLogv) can't be encoded.
- asprintf and vasprintf: these aren't part of the C99 standard
library, so we really shouldn't be defining them as builtins in
the general case (and we don't seem to have the machinery to make
them builtins only on certain targets and depending on whether
extensions are enabled).
llvm-svn: 64512
etc.) when we perform name lookup on them. This ensures that we
produce the correct signature for these functions, which has two
practical impacts:
1) When we're supporting the "implicit function declaration" feature
of C99, these functions will be implicitly declared with the right
signature rather than as a function returning "int" with no
prototype. See PR3541 for the reason why this is important (hint:
GCC always predeclares these functions).
2) If users attempt to redeclare one of these library functions with
an incompatible signature, we produce a hard error.
This patch does a little bit of work to give reasonable error
messages. For example, when we hit case #1 we complain that we're
implicitly declaring this function with a specific signature, and then
we give a note that asks the user to include the appropriate header
(e.g., "please include <stdlib.h> or explicitly declare 'malloc'"). In
case #2, we show the type of the implicit builtin that was incorrectly
declared, so the user can see the problem. We could do better here:
for example, when displaying this latter error message we say
something like:
'strcpy' was implicitly declared here with type 'char *(char *, char
const *)'
but we should really print out a fake code line showing the
declaration, like this:
'strcpy' was implicitly declared here as:
char *strcpy(char *, char const *)
This would also be good for printing built-in candidates with C++
operator overloading.
The set of C library functions supported by this patch includes all
functions from the C99 specification's <stdlib.h> and <string.h> that
(a) are predefined by GCC and (b) have signatures that could cause
codegen issues if they are treated as functions with no prototype
returning and int. Future work could extend this set of functions to
other C library functions that we know about.
llvm-svn: 64504
given name in a given scope is marked as "overloadable", every
function declaration and definition with that same name and in that
same scope needs to have the "overloadable" attribute. Essentially,
the "overloadable" attribute is not part of attribute merging, so it
must be specified even for redeclarations. This keeps users from
trying to be too sneaky for their own good:
double sin(double) __attribute__((overloadable)); // too sneaky
#include <math.h>
Previously, this would have made "sin" overloadable, and therefore
given it a mangled name. Now, we get an error inside math.h when we
see a (re)declaration of "sin" that doesn't have the "overloadable"
attribute.
llvm-svn: 64414
This commit adds a new attribute, "overloadable", that enables C++
function overloading in C. The attribute can only be added to function
declarations, e.g.,
int *f(int) __attribute__((overloadable));
If the "overloadable" attribute exists on a function with a given
name, *all* functions with that name (and in that scope) must have the
"overloadable" attribute. Sets of overloaded functions with the
"overloadable" attribute then follow the normal C++ rules for
overloaded functions, e.g., overloads must have different
parameter-type-lists from each other.
When calling an overloaded function in C, we follow the same
overloading rules as C++, with three extensions to the set of standard
conversions:
- A value of a given struct or union type T can be converted to the
type T. This is just the identity conversion. (In C++, this would
go through a copy constructor).
- A value of pointer type T* can be converted to a value of type U*
if T and U are compatible types. This conversion has Conversion
rank (it's considered a pointer conversion in C).
- A value of type T can be converted to a value of type U if T and U
are compatible (and are not both pointer types). This conversion
has Conversion rank (it's considered to be a new kind of
conversion unique to C, a "compatible" conversion).
Known defects (and, therefore, next steps):
1) The standard-conversion handling does not understand conversions
involving _Complex or vector extensions, so it is likely to get
these wrong. We need to add these conversions.
2) All overloadable functions with the same name will have the same
linkage name, which means we'll get a collision in the linker (if
not sooner). We'll need to mangle the names of these functions.
llvm-svn: 64336
than a Decl, which gives us some more flexibility to express the
results with the type system. There are no clients using this
flexibility yet, but it's meant to be able to describe qualified names
as written in the source (e.g., "foo::type") or template-ids that name
a class template specialization (e.g., "std::vector<INT>").
DeclSpec's TST_typedef has become TST_typename, to reflect its use to
describe types found by name (that may or may not be typedefs). The
type representation of a DeclSpec with TST_typename is an opaque
QualType pointer. All users of TST_typedef, both direct and indirect,
have been updated for these changes.
llvm-svn: 64141
- Made allocation of Stmt objects using vanilla new/delete a *compiler
error* by making this new/delete "protected" within class Stmt.
- Now the only way to allocate Stmt objects is by using the new
operator that takes ASTContext& as an argument. This ensures that
all Stmt nodes are allocated from the same (pool) allocator.
- Naturally, these two changes required that *all* creation sites for
AST nodes use new (ASTContext&). This is a large patch, but the
majority of the changes are just this mechanical adjustment.
- The above changes also mean that AST nodes can no longer be
deallocated using 'delete'. Instead, one most do
StmtObject->Destroy(ASTContext&) or do
ASTContextObject.Deallocate(StmtObject) (the latter not running the
'Destroy' method).
Along the way I also...
- Made CompoundStmt allocate its array of Stmt* using the allocator in
ASTContext (previously it used std::vector). There are a whole
bunch of other Stmt classes that need to be similarly changed to
ensure that all memory allocated for ASTs comes from the allocator
in ASTContext.
- Added a new smart pointer ExprOwningPtr to Sema.h. This replaces
the uses of llvm::OwningPtr within Sema, as llvm::OwningPtr used
'delete' to free memory instead of a Stmt's 'Destroy' method.
Big thanks to Doug Gregor for helping with the acrobatics of making
'new/delete' private and the new smart pointer ExprOwningPtr!
llvm-svn: 63997
redeclarations. For example, checks that a class template
redeclaration has the same template parameters as previous
declarations.
Detangled class-template checking from ActOnTag, whose logic was
getting rather convoluted because it tried to handle C, C++, and C++
template semantics in one shot.
Made some inroads toward eliminating extraneous "declaration does not
declare anything" errors by adding an "error" type specifier.
llvm-svn: 63973
- Changes Lookup*Name functions to return NamedDecls, instead of
Decls. Unfortunately my recent statement that it will simplify lot of
code, was not quite right, but it simplifies some...
- Makes MergeLookupResult SmallPtrSet instead of vector, following
Douglas suggestions.
- Adds %qN format for printing qualified names to Diagnostic.
- Avoids searching for using-directives in Scopes, which are not
DeclScope, during unqualified name lookup.
llvm-svn: 63739
elaborated-type-specifier declarations into outer scopes while
retaining their proper lexical scope. This way is simpler and more
consistent with the way DeclContexts work, and also fixes
http://llvm.org/bugs/show_bug.cgi?id=3430
llvm-svn: 63581
- Support initialization of reference members; complain if any
reference members are left uninitialized.
- Use C++ copy-initialization for initializing each element (falls
back to constraint checking in C)
- Make sure we diagnose when one tries to provide an initializer
list for a non-aggregate.
- Don't complain about empty initializers in C++ (they are permitted)
- Unrelated but necessary: don't bother trying to convert the
decl-specifier-seq to a type when we're dealing with a C++
constructor, destructor, or conversion operator; it results in
spurious warnings.
llvm-svn: 63431
type" rather than the C definition. We do this because both C99 and
Clang always use "aggregate type" as "aggregate or union type", and
the C++ definition includes union types.
llvm-svn: 63395
LookupName et al. Instead, use an enum and a bool to describe its
contents.
Optimized the C/Objective-C path through LookupName, eliminating any
unnecessarily C++isms. Simplify IdentifierResolver::iterator, removing
some code and arguments that are no longer used.
Eliminated LookupDeclInScope/LookupDeclInContext, moving all callers
over to LookupName, LookupQualifiedName, or LookupParsedName, as
appropriate.
All together, I'm seeing a 0.2% speedup on Cocoa.h with PTH and
-disable-free. Plus, we're down to three name-lookup routines.
llvm-svn: 63354
This results in a 1.7% improvement for "Cocoa.h". If we can figure out how to return a "Decl *", rather than a Sema::LookupResult(), we will likely bump the speedup from 1.7%->2.5%. I verified this, however couldn't get it to work without breaking a fair number of C++ test cases. Will discuss with Doug offline.
llvm-svn: 63320
represents an implicit value-initialization of a subobject of a
particular type. This replaces the (ab)use of CXXZeroValueInitExpr
within initializer lists for the "holes" that occur due to the use of
C99 designated initializers.
The new test case is currently XFAIL'd, because CodeGen's
ConstExprEmitter (in lib/CodeGen/CGExprConstant.cpp) needs to be
taught to value-initialize when it sees ImplicitValueInitExprs.
llvm-svn: 63317
The previous interface was very confusing. This is much more explicit, which will be easier to understand/optimize/convert.
The plan is to eventually deprecate both of these functions. For now, I'm focused on performance.
llvm-svn: 63256
The approach I've taken in this patch is relatively straightforward,
although the code itself is non-trivial. Essentially, as we process
an initializer list we build up a fully-explicit representation of the
initializer list, where each of the subobject initializations occurs
in order. Designators serve to "fill in" subobject initializations in
a non-linear way. The fully-explicit representation makes initializer
lists (both with and without designators) easy to grok for codegen and
later semantic analyses. We keep the syntactic form of the initializer
list linked into the AST for those clients interested in exactly what
the user wrote.
Known limitations:
- Designating a member of a union that isn't the first member may
result in bogus initialization (we warn about this)
- GNU array-range designators are not supported (we warn about this)
llvm-svn: 63242
Even though Sema::LookupDecl() is deprecated, it's still used all over the place. Simplifying the interface will make it easier to understand/optimize/convert.
llvm-svn: 63210
Even though Sema::LookupDecl() is deprecated, it's still used all over the place. Simplifying the interface will make it easier to understand/optimize/convert.
llvm-svn: 63208
.def file for each library. This means that adding a diagnostic
to sema doesn't require all the other libraries to be rebuilt.
Patch by Anders Johnsen!
llvm-svn: 63111
special action, inside function prototype scope. This avoids confusion
when we try to inject these parameters into the scope of the function
body before the function itself has been added to the surrounding
scope. Fixes <rdar://problem/6097326>.
llvm-svn: 62849
designated initializers. This implementation should cover all of the
constraints in C99 6.7.8, including long, complex designations and
computing the size of incomplete array types initialized with a
designated initializer. Please see the new test-case and holler if you
find cases where this doesn't work.
There are still some wrinkles with GNU's anonymous structs and
anonymous unions (it isn't clear how these should work; we'll just
follow GCC's lead) and with designated initializers for the members of a
union. I'll tackle those very soon.
CodeGen is still nonexistent, and there's some leftover code in the
parser's representation of designators that I'll also need to clean up.
llvm-svn: 62737
function DeclaratorChunk in common cases. This uses a fixed array in
Declarator when it is small enough for the first function declarator chunk
in a declarator.
This eliminates all malloc/free traffic from DeclaratorChunk::getFunction
when running on Cocoa.h except for five functions: signal/bsd_signal/sigset,
which have multiple Function DeclChunk's, and
CFUUIDCreateWithBytes/CFUUIDGetConstantUUIDWithBytes, which take more than
16 arguments.
This patch was pair programmed with Steve.
llvm-svn: 62599
