Commit Graph

25 Commits

Author SHA1 Message Date
Richard Smith b23c5e8c3d [c++20] Implement P0846R0: allow (ADL-only) calls to template-ids whose
template name is not visible to unqualified lookup.

In order to support this without a severe degradation in our ability to
diagnose typos in template names, this change significantly restructures
the way we handle template-id-shaped syntax for which lookup of the
template name finds nothing.

Instead of eagerly diagnosing an undeclared template name, we now form a
placeholder template-name representing a name that is known to not find
any templates. When the parser sees such a name, it attempts to
disambiguate whether we have a less-than comparison or a template-id.
Any diagnostics or typo-correction for the name are delayed until its
point of use.

The upshot should be a small improvement of our diagostic quality
overall: we now take more syntactic context into account when trying to
resolve an undeclared identifier on the left hand side of a '<'. In
fact, this works well enough that the backwards-compatible portion (for
an undeclared identifier rather than a lookup that finds functions but
no function templates) is enabled in all language modes.

llvm-svn: 360308
2019-05-09 03:31:27 +00:00
Richard Smith 97135cc94a [modules] Simplify and generalize the existing rule for finding hidden
declarations in redeclaration lookup. A declaration is now visible to
lookup if:

 * It is visible (not in a module, or in an imported module), or
 * We're doing redeclaration lookup and it's externally-visible, or
 * We're doing typo correction and looking for unimported decls.

We now support multiple modules having different internal-linkage or no-linkage
definitions of the same name for all entities, not just for functions,
variables, and some typedefs. As previously, if multiple such entities are
visible, any attempt to use them will result in an ambiguity error.

This patch fixes the linkage calculation for a number of entities where we
previously didn't need to get it right (using-declarations, namespace aliases,
and so on).  It also classifies enumerators as always having no linkage, which
is a slight deviation from the C++ standard's definition, but not an observable
change outside modules (this change is being discussed on the -core reflector
currently).

This also removes the prior special case for tag lookup, which made some cases
of this work, but also led to bizarre, bogus "must use 'struct' to refer to type
'Foo' in this scope" diagnostics in C++.

llvm-svn: 252960
2015-11-12 22:19:45 +00:00
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
Richard Smith f2b1eb9eb2 [modules] Better support for redefinitions of an entity from the same module.
Support this across module save/reload and extend the 'missing import'
diagnostics with a list of providing modules.

llvm-svn: 239750
2015-06-15 20:15:48 +00:00
Ben Langmuir 9eb229bfe5 Require a module.map file to load a module
Removes some old code that allowed a module to be loaded from a pcm file
even if the module.map could not be found.  Also update a number of
tests that relied on the old behavior.

llvm-svn: 199852
2014-01-22 23:19:39 +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 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
Richard Smith 7aed66bbee When disambiguating an expression-statement from a declaraton-statement, if the
statement starts with an identifier for which name lookup will fail either way,
look at later tokens to disambiguate in order to improve error recovery.

llvm-svn: 162464
2012-08-23 20:19:14 +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 da82e703d1 Eliminate the uglified keyword __import_module__ for importing
modules. This leaves us without an explicit syntax for importing
modules in C/C++, because such a syntax needs to be discussed
first. In Objective-C/Objective-C++, the @import syntax is used to
import modules.

Note that, under -fmodules, C/C++ programs can import modules via the
#include mechanism when a module map is in place for that header. This
allows us to work with modules in C/C++ without committing to a syntax.

llvm-svn: 147467
2012-01-03 19:32:59 +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 70db54f18d Eliminate the -emit-module option, which emitted a module by parsing a
source file (e.g., a header). Immediately steal this useful option
name for building modules from a module map file.

llvm-svn: 145444
2011-11-29 22:42:06 +00:00
Douglas Gregor 84febf4a4d Migrate a few more modules tests over to -emit-module-from-map.
llvm-svn: 144779
2011-11-16 05:16:30 +00:00
Douglas Gregor 1735f4e752 For modules, use a hash of the compiler version, language options, and
target triple to separate modules built under different
conditions. The hash is used to create a subdirectory in the module
cache path where other invocations of the compiler (with the same
version, language options, etc.) can find the precompiled modules.

llvm-svn: 139662
2011-09-13 23:15:45 +00:00
Douglas Gregor a057a58048 Add a struct-size check for modules when dealing with module-private fields
llvm-svn: 139597
2011-09-13 15:37:05 +00:00
Douglas Gregor 1e44e02292 Introduce a cc1-level option to provide the path to the module cache,
where the compiler will look for module files. Eliminates the
egregious hack where we looked into the header search paths for
modules.

llvm-svn: 139538
2011-09-12 20:41:59 +00:00
Douglas Gregor 41866816ce Diagnose attempt to mark function-local declarations as __module_private__.
llvm-svn: 139519
2011-09-12 18:37:38 +00:00
Douglas Gregor 3baa6702ab Allow __module_private__ on fields
llvm-svn: 139499
2011-09-12 16:11:24 +00:00
Douglas Gregor fc33bcfc4a Remove the restriction on module-private friends. Since the friend
declaration may be the first declaration, we want the ability to that
declaration to be marked module-private.

llvm-svn: 139497
2011-09-12 15:48:15 +00:00
Douglas Gregor 6422642a1d Friends cannot be declared module-private
llvm-svn: 139411
2011-09-09 21:14:29 +00:00
Douglas Gregor 3c7cd6a0c4 Specializations cannot be module-hidden. Diagnose attempts to do so.
llvm-svn: 139406
2011-09-09 20:53:38 +00:00
Douglas Gregor 2820e6923a __module_private__ is inherited by redeclarations of an entity, and
must also be present of the first declaration of that entity.

llvm-svn: 139384
2011-09-09 19:05:14 +00:00
Douglas Gregor ef15bdbe1a Propagate __module_private__ from previous declarations to later
declarations.

llvm-svn: 139380
2011-09-09 18:32:39 +00:00
Douglas Gregor 26701a4371 Modules: introduce the __module_private__ declaration specifier, which
indicates that a declaration is only visible within the module it is
declared in.

llvm-svn: 139348
2011-09-09 02:06:17 +00:00