Commit Graph

33 Commits

Author SHA1 Message Date
Dávid Bolvanský 1da13237a4 [Diagnostics] Try to improve warning message for -Wreturn-type
Summary: I agree with https://easyaspi314.github.io/gcc-vs-clang.html?fbclid=IwAR1VA0qxiWVUusOQUv5z7JESS7ZpeJy-UqAI5mnJscofGLqXcqeErIUB2gU, current warning message is not very good. We should try to improve it..

Reviewers: rsmith, aaron.ballman, easyaspi314

Reviewed By: aaron.ballman

Subscribers: arphaman, Quuxplusone, mehdi_amini, hiraditya, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D69762
2019-11-09 17:54:58 +01:00
Richard Smith 47972afd10 [modules] Simplify -cc1 interface for enabling implicit module maps.
We used to have a flag to enable module maps, and two more flags to enable
implicit module maps. This is all redundant; we don't need any flag for
enabling module maps in the abstract, and we don't usually have -fno- flags for
-cc1. We now have just a single flag, -fimplicit-module-maps, that enables
implicitly searching the file system for module map files and loading them.

The driver interface is unchanged for now. We should probably rename
-fmodule-maps to -fimplicit-module-maps at some point.

llvm-svn: 239789
2015-06-16 00:08:24 +00:00
Andy Gibbs fcc699aee8 Extended VerifyDiagnosticConsumer to also verify source file for diagnostic.
VerifyDiagnosticConsumer previously would not check that the diagnostic and
its matching directive referenced the same source file.  Common practice was
to create directives that referenced other files but only by line number,
and this led to problems such as when the file containing the directive
didn't have enough lines to match the location of the diagnostic in the
other file, leading to bizarre file formatting and other oddities.

This patch causes VerifyDiagnosticConsumer to match source files as well as
line numbers.  Therefore, a new syntax is made available for directives, for
example:

// expected-error@file:line {{diagnostic message}}

This extends the @line feature where "file" is the file where the diagnostic
is generated.  The @line syntax is still available and uses the current file
for the diagnostic.  "file" can be specified either as a relative or absolute
path - although the latter has less usefulness, I think!  The #include search
paths will be used to locate the file and if it is not found an error will be
generated.

The new check is not optional: if the directive is in a different file to the
diagnostic, the file must be specified.  Therefore, a number of test-cases
have been updated with regard to this.

This closes out PR15613.

llvm-svn: 179677
2013-04-17 08:06:46 +00:00
Douglas Gregor 6168bd2323 Ensure that the identifier chains have the most recent declaration after module deserialization.
This commit introduces a set of related changes to ensure that the
declaration that shows up in the identifier chain after deserializing
declarations with a given identifier is, in fact, the most recent
declaration. The primary change involves waiting until after we
deserialize and wire up redeclaration chains before updating the
identifier chains. There is a minor optimization in here to avoid
recursively deserializing names as part of looking to see whether
top-level declarations for a given name exist.

A related change that became suddenly more urgent is to property
record a merged declaration when an entity first declared in the
current translation unit is later deserialized from a module (that had
not been loaded at the time of the original declaration). Since we key
off the canonical declaration (which is parsed, not from an AST file)
for emitted redeclarations, we simply record this as a merged
declaration during AST writing and let the readers merge them.

Re-fixes <rdar://problem/13189985>, presumably for good this time.

llvm-svn: 175447
2013-02-18 15:53:43 +00:00
Douglas Gregor 35b04d6fd2 Rename -fmodule-cache-path <blah> to -fmodules-cache-path=<blah> for consistency.
llvm-svn: 174645
2013-02-07 19:01:24 +00:00
Douglas Gregor c50d4924eb Use @import rather than @__experimental_modules_import, since the
latter is rather a mess to type.

llvm-svn: 169919
2012-12-11 22:11:52 +00:00
Axel Naumann 63469422c4 Merge pending instantiations instead of overwriting existing ones.
Check whether a pending instantiation needs to be instantiated (or whether an instantiation already exists).
Verify the size of the PendingInstantiations record (was only checking size of existing PendingInstantiations).

Migrate Obj-C++ part of redecl-merge into separate test, now that this is growing.
templates.mm: test that CodeGen has seen exactly one definition of template instantiations.
redecl-merge.m: use "@" specifier for expected-diagnostics.

llvm-svn: 164993
2012-10-02 09:09:43 +00:00
Axel Naumann 866ba3e365 Also merge template redeclarations.
Don't require specializations (of existing and read template) to be unique.

llvm-svn: 164931
2012-10-01 09:18:00 +00:00
Axel Naumann a31dee2e04 Bring ASTReader and Writer into sync for the case where a canonical template specialization was written, which is non-canonical at the time of reading: force the reading of the ClassTemplateDecl if it was written.
The easiest way out is to store whether the decl was canonical at the time of writing.
Add test.

llvm-svn: 164927
2012-10-01 07:34:47 +00:00
Patrick Beard acfbe9e1f2 Added a new attribute, objc_root_class, which informs the compiler when a root class is intentionally declared.
The warning this inhibits, -Wobjc-root-class, is opt-in for now. However, all clang unit tests that would trigger
the warning have been updated to use -Wno-objc-root-class. <rdar://problem/7446698>

llvm-svn: 154187
2012-04-06 18:12:22 +00:00
Ted Kremenek c1e4dd0e8e Change @import to @__experimental_modules_import. We are not ready to commit to a particular syntax for modules,
and don't have time to push it forward in the near future.

llvm-svn: 151841
2012-03-01 22:07:04 +00:00
Douglas Gregor c03c52ea01 When deserializing the definition of a C++ class/ObjC class/ObjC
protocol, record the definition pointer in the canonical declaration
for that entity, and then propagate that definition pointer from the
canonical declaration to all other deserialized declarations. This
approach works well even when deserializing declarations that didn't
know about the original definition, which can occur with modules.

A nice bonus from this definition-deserialization approach is that we
no longer need update records when a definition is added, because the
redeclaration chains ensure that the if any declaration is loaded, the
definition will also get loaded.

llvm-svn: 148223
2012-01-15 18:08:05 +00:00
Douglas Gregor 87ea58f5cd (Implicit) parameters deserialized as part of a function type must not
get added to the identifier chains as part of deserialization, because
they should not be visible to name lookup.

llvm-svn: 148159
2012-01-13 23:49:34 +00:00
Douglas Gregor dbd93bfc2d Always allow redefinition of typedefs when modules are enabled. This
is important because it's fairly common for headers (especially system
headers) to want to provide only those typedefs needed for that
particular header, based on some guard macro, e.g.,

#ifndef _SIZE_T
#define _SIZE_T
typedef long size_t;
#endif

which is repeated in a number of headers. The guard macro protects
against duplicate definitions. However, this means that only the first
occurrence of this pattern actually defines size_t, so the submodule
corresponding to this header has the only visible definition. If a
user then imports a different submodule from the same module, size_t
will be known but not visible, and therefore cannot be used.

By allowing redefinition of typedefs, each header that wants to define
size_t can do so independently, so it will be available in the
corresponding submodules.

llvm-svn: 147775
2012-01-09 15:36:04 +00:00
Douglas Gregor 5c193c7ed6 When we're performing name lookup for a tag, we still allow ourselves
to see hidden declarations because every tag lookup is effectively a
redeclaration lookup. For example, image that

  struct foo;

is declared in a submodule that is known but hasn't been imported. If
someone later writes

  struct foo *foo_p;

then "struct foo" is either a reference or a redeclaration. To keep
the redeclaration chains sound, we treat it like a redeclaration for
name-lookup purposes.

llvm-svn: 147588
2012-01-05 01:11:47 +00:00
Douglas Gregor b8c6f1e950 Implement declaration merging for variables in disjoint modules.
llvm-svn: 147535
2012-01-04 17:21:36 +00:00
Douglas Gregor b258569405 Implement declaration merging for non-template functions from
different modules. This implementation is a first approximation of
what we want, using only the function type to determine
equivalence. Later, we'll want to deal with some of the more subtle
issues, including:

  - C allows a prototyped declaration and a non-prototyped declaration
    to be merged, which we should support
  - We may want to ignore the return type when merging, then
    complain if the return types differ. Or, we may want to leave it
    as it us, so that we only complain if overload resolution
    eventually fails.
  - C++ non-static member functions need to consider cv-qualifiers
    and ref-qualifiers.
  - Function templates need to consider the template parameters and
    return type.
  - Function template specializations will have special rules.
  - We can now (accidentally!) end up overloading in C, even without
    the "overloadable" attribute, and will need to detect this at some
    point.
  
The actual detection of "is this an overload?" is implemented by
Sema::IsOverload(), which will need to be moved into the AST library
for re-use here. That will be a future refactor.

llvm-svn: 147534
2012-01-04 17:13:46 +00:00
Douglas Gregor b59643baf6 Test "merging" of typedef types across distinct modules. At present,
the AST reader doesn't actually perform a merge, because name lookup
knows how to merge identical typedefs together.

As part of this, teach C/Objective-C name lookup to return multiple
results in all cases, rather than first digging through the attributes
to see if the value is overloadable. This way, we'll catch ambiguous
lookups in C/Objective-C.

llvm-svn: 147498
2012-01-03 23:26:26 +00:00
Douglas Gregor 2009ceed82 Implement cross-module declaration merging for tag declarations, so
that if two modules A and B both contain a declaration of a tag such
as

  struct X;

and those two modules are unrelated, the two declarations of X will be
merged into a single redeclaration chain.

llvm-svn: 147488
2012-01-03 22:46:00 +00:00
Douglas Gregor 22d0974b40 Introduce a non-uglified syntax for module imports in Objective-C:
@import identifier [. identifier]* ;

llvm-svn: 147452
2012-01-03 18:04:46 +00:00
Douglas Gregor e097d4ba26 Don't attempt to merge a deserialized declaration with existing
declarations in the AST unless modules are enabled. This case doesn't
come up with precompiled headers, and it isn't cheap.

llvm-svn: 147451
2012-01-03 17:31:38 +00:00
Douglas Gregor da38930cf3 Implement declaration merging for Objective-C protocols across
multiple, disjoint modules. There is far too much duplicating with the
ObjCInterfaceDecl case here, which I'll eliminate shortly.

llvm-svn: 147417
2012-01-01 21:47:52 +00:00
Douglas Gregor 32c1757730 Wire up redeclaration chains for Objective-C protocols, so that both
forward declarations and definitions of an Objective-C protocol are
represented within a single chain of ObjCProtocolDecls.

llvm-svn: 147412
2012-01-01 20:30:41 +00:00
Douglas Gregor 464b0ca61a Serialize the AST reader's mapping from canonical declarations to the
set of (previously-canonical) declaration IDs to the module file, so
that future AST reader instances that load the module know which
declarations are merged. This is important in the fairly tricky case
where a declaration of an entity, e.g.,

  @class X;

occurs before the import of a module that also declares that
entity. We merge the declarations, and record the fact that the
declaration of X loaded from the module was merged into the (now
canonical) declaration of X that we parsed.

llvm-svn: 147181
2011-12-22 21:40:42 +00:00
Douglas Gregor 0475cd88c9 If we end up merging an Objective-C class with an existing Objective-C
class that comes from a different module file, make sure that we load
all of the pending declarations for the original declaration.

llvm-svn: 147168
2011-12-22 19:44:59 +00:00
Douglas Gregor 022857e03d When deserializing an Objective-C class, check whether we have another
declaration of that same class that either came from some other module
or occurred in the translation unit loading the module. In this case,
we need to merge the two redeclaration chains immediately so that all
such declarations have the same canonical declaration in the resulting
AST (even though they don't in the module files we've imported).

Focusing on Objective-C classes until I'm happy with the design, then
I'll both (1) extend this notion to other kinds of declarations, and
(2) optimize away this extra checking when we're not dealing with
modules. For now, doing this checking for PCH files/preambles gives us
better testing coverage.

llvm-svn: 147123
2011-12-22 01:48:48 +00:00
Douglas Gregor 21823bfe31 When performing name lookup for a redeclaration, ignore module
visibility restrictions. This ensures that all declarations of the
same entity end up in the same redeclaration chain, even if some of
those declarations aren't visible. While this may seem unfortunate to
some---why can't two C modules have different functions named
'f'?---it's an acknowedgment that a module does not introduce a new
"namespace" of names.

As part of this, stop merging the 'module-private' bit from previous
declarations to later declarations, because we want each declaration
in a module to stand on its own because this can effect, for example,
submodule visibility.

Note that this notion of names that are invisible to normal name
lookup but are available for redeclaration lookups is how we should
implement friend declarations and extern declarations within local
function scopes. I'm not tackling that problem now.

llvm-svn: 146980
2011-12-20 18:11:52 +00:00
Douglas Gregor e80b31f7f9 Once we have fully deserialized a redeclaration chain for something
with a definition pointer (e.g., C++ and Objective-C classes), zip
through the redeclaration chain to make sure that all of the
declarations point to the definition data. 

As part of this, realized again why the first redeclaration of an
entity in a file is important, and brought back that idea.

llvm-svn: 146886
2011-12-19 19:00:47 +00:00
Douglas Gregor 074a409622 Re-implement (de-)serialization of redeclaration chains for
redeclaration templates (RedeclarableTemplateDecl), similarly to the
way (de-)serialization is implemented for Redeclarable<T>. In the
process, found a simpler formulation for handling redeclaration
chains and implemented that in both places.

The new test establishes that we're building the redeclaration chains
properly. However, the FIXME indicates where we're tickling a
different bug that has to do with us not setting the DefinitionData
pointer properly in redeclarations that we detected after the
definition itself was deserialized. The (separable) fix for that bug
is forthcoming.

llvm-svn: 146883
2011-12-19 18:19:24 +00:00
Douglas Gregor 2682ba0ed3 The submodule offset map can introduce "empty" remapping entries for
imported modules that don't introduce any new entities of a particular
kind. Allow these entries to be replaced with entries for another
loaded module.

In the included test case, selectors exhibit this behavior.

llvm-svn: 146870
2011-12-19 16:14:14 +00:00
Douglas Gregor 9f562c8d9e Optimize serialized representation of redeclarable declarations for
which there are no redeclarations. This reduced by size of the PCH
file for Cocoa.h by ~650k: ~536k of that was in the new
LOCAL_REDECLARATIONS table, which went from a ridiculous 540k down to
an acceptable 3.5k, while the rest was due to the more compact
abbreviated representation of redeclarable declaration kinds (which no
longer need to store the 'first' declaration ID).

llvm-svn: 146869
2011-12-19 15:27:36 +00:00
Douglas Gregor f4b339decf Make sure this test works in C++, too
llvm-svn: 146868
2011-12-19 14:42:41 +00:00
Douglas Gregor 05f10357a9 Completely re-implement (de-)serialization of declaration
chains. The previous implementation relied heavily on the declaration
chain being stored as a (circular) linked list on disk, as it is in
memory. However, when deserializing from multiple modules, the
different chains could get mixed up, leading to broken declaration chains.

The new solution keeps track of the first and last declarations in the
chain for each module file. When we load a declaration, we search all
of the module files for redeclarations of that declaration, then
splice together all of the lists into a coherent whole (along with any
redeclarations that were actually parsed). 

As a drive-by fix, (de-)serialize the redeclaration chains of
TypedefNameDecls, which had somehow gotten missed previously. Add a
test of this serialization.

This new scheme creates a redeclaration table that is fairly large in
the PCH file (on the order of 400k for Cocoa.h's 12MB PCH file). The
table is mmap'd in and searched via a binary search, but it's still
quite large. A future tweak will eliminate entries for declarations
that have no redeclarations anywhere, and should
drastically reduce the size of this table.

llvm-svn: 146841
2011-12-17 23:38:30 +00:00