Commit Graph

26 Commits

Author SHA1 Message Date
Alan Zhao 6f2b347895 Add missing `struct` keyword to the test p2-2.cpp
While working on D53847, I noticed that this test would fail once we
started recognizing the types in the modified `export` statement [0].
The tests would fail because Clang would emit a "declaration does not
declare anything" diagnostic instead of the expected namespace scope
diagnostic.

I believe that the test is currently incorrectly passing because Clang
doesn't parse the type and therefore doesn't treat the statement as a
declaration. My understanding is that the intention of this test case is
that it wants to export a `struct` type, which I believe requires a
`struct` keyword, even for types with template parameters. With this
change, the only error with these two statements should be the
namespace scope issue.

[0]: https://reviews.llvm.org/D53847?id=462032#inline-1297053

Reviewed By: erichkeane

Differential Revision: https://reviews.llvm.org/D134578
2022-09-28 09:48:00 -07:00
Chuanqi Xu fed71b04fb [NFC] Add an invalid test case for clang/test/CXX/module/module.reach/ex1.cpp 2022-08-31 13:02:00 +08:00
Chuanqi Xu 9c04851cf5 [C++20] [Module] Support reachable definition initially/partially
This patch introduces a new kind of ModuleOwnershipKind as
ReachableWhenImported. This intended the status for reachable described
at: https://eel.is/c++draft/module.reach#3.

Note that this patch is not intended to support all semantics about
reachable semantics. For example, this patch didn't implement discarded
declarations in GMF. (https://eel.is/c++draft/module.global.frag#3).

This fixes: https://bugs.llvm.org/show_bug.cgi?id=52281 and
https://godbolt.org/z/81f3ocjfW.

Reviewed By: rsmith, iains

Differential Revision: https://reviews.llvm.org/D113545
2022-06-29 12:48:48 +08:00
Chuanqi Xu 7a541406b5 Revert "[C++20] [Modules] Implement Reachable initiallly"
This reverts commit a223ba0a69.

The previous commit don't contain additional information, which is bad.
2022-06-29 12:43:26 +08:00
Chuanqi Xu a223ba0a69 [C++20] [Modules] Implement Reachable initiallly 2022-06-29 12:32:31 +08:00
Chuanqi Xu ce2257d69f [C++20] [Modules] Judge current module correctly
Now the implementation would accept following code:
```
//--- impl.cppm
module M:impl;
class A {};

//--- M.cppm
export module M;
import :impl;

//--- Use.cpp
import M;
void test() {
    A a; // Expected error. A is not visible here.
}
```

which is clearly wrong.  The root cause is the implementation of
`isInCurrentModule` would return true if the module is a partition! So
in the above example, although Use.cpp is not a module unit,
`isInCurrentModule ` would still return true when the compiler tries to
see if the owning module of `A` is the current module. I believe this is
an oversight. This patch tries to fix this problem.

Reviewed By: iains

Differential Revision: https://reviews.llvm.org/D123837
2022-04-21 11:09:55 +08:00
Iain Sandoe f60dc3caa6 [C++20][Modules] Adjust handling of exports of namespaces and using-decls.
This adjusts the handling for:

export module  M;

export namespace {};

export namespace N {};
export using namespace N;

In the first case, we were allowing empty anonymous namespaces
as part of an extension allowing empty top-level entities, but that seems
inappropriate in this case, since the linkage would be internal for the
anonymous namespace.  We now report an error for this.

The second case was producing a warning diagnostic that this was
accepted as an extension - however the C++20 standard does allow this
as well-formed.

In the third case we keep the current practice that this is accepted with a
warning (as an extension). The C++20 standard says it's an error.

We also ensure that using decls are only applied to items with external linkage.

This adjusts error messages for exports involving redeclarations in modules to
be more specific about the reason that the decl has been rejected.

Differential Revision: https://reviews.llvm.org/D122119
2022-04-08 08:57:37 +01:00
Chuanqi Xu ae4eb938c0 [NFC] [C++20] [Modules] Add test to show private module fragment is not allowed in partition unit 2022-03-09 19:05:54 +08:00
Iain Sandoe 69350e569d [C++20][Modules][3/8] Initial handling for module partitions.
This implements the parsing and recognition of module partition CMIs
and removes the FIXMEs in the parser.

Module partitions are recognised in the base computation of visibility,
however additional amendments to visibility follow in subsequent patches.

Differential Revision: https://reviews.llvm.org/D118586
2022-02-24 09:01:09 +00:00
Chuanqi Xu 3504937dfb [C++20] [Modules] Don't create multiple global module fragment
Since the serialization code would recognize modules by names and the
name of all global module fragment is <global>, so that the
serialization code would complain for the same module.

This patch fixes this by using a unique global module fragment in Sema.
Before this patch, the compiler would fail on an assertion complaining
the duplicated modules.

Reviewed By: urnathan, rsmith

Differential Revision: https://reviews.llvm.org/D115610
2022-02-08 11:52:09 +08:00
Chuanqi Xu 5c1f7b296a [C++20] [Modules] Only check decls under namespace scope in CheckRedeclarationExported
Since only the decls inhabit in a namespace scope could be exported, it
is not meaningful to check it in CheckRedeclarationExported, which
implements [module.interface]/p6.

Reviewed By: urnathan

Differential Revision: https://reviews.llvm.org/D118120
2022-01-26 10:54:52 +08:00
Chuanqi Xu 3a3af2bbc9 [C++20] [Module] fix bug 47716 and implement [module.interface]/p6
This fixes bug 47716.

According to [module.interface]p2, it is meaningless to export an entity
which is not in namespace scope.
The reason why the compiler crashes is that the compiler missed
ExportDecl when the compiler traverse the subclass of DeclContext. So
here is the crash.

Also, the patch implements [module.interface]p6 in
Sema::CheckRedeclaration* functions.

Reviewed By: aaron.ballman, urnathan

Differential Revision: https://reviews.llvm.org/D112903
2022-01-24 10:25:25 +08:00
Chuanqi Xu 9db8162820 [NFC] Format .cppm files in tests 2021-12-13 23:32:25 +08:00
Nico Weber 45158b1804 Revert "[NFC] format .cppm files in test"
This reverts commit 7c51a12833.
Breaks SemaCXX/modules-ts.cppm in check-clang.
2021-12-13 07:13:17 -05:00
Chuanqi Xu 7c51a12833 [NFC] format .cppm files in test 2021-12-13 19:52:31 +08:00
Chuanqi Xu 9791b58951 [C++20 Modules] Don't create global module fragment for extern linkage declaration in GMF already
Previously we would create global module fragment for extern linkage
declaration which is alreday in global module fragment. However, it is
clearly redundant to do so. This patch would check if the extern linkage
declaration are already in GMF before we create a GMF for it.
2021-12-09 13:55:15 +08:00
Chuanqi Xu e587372f85 [C++20] [Module] Support extern C/C++ semantics
According to [module.unit]p7.2.3, a declaration within a linkage-specification
should be attached to the global module.
This let user to forward declare types across modules.

Reviewed by: rsmith, aaron.ballman

Differential Revision: https://reviews.llvm.org/D110215
2021-12-08 13:29:16 +08:00
Richard Smith 0a088ead85 Improve diagnostics for missing import / #include of module.
Fix a few bugs where we would fail to properly determine header to
module correspondence when determining whether to suggest a #include or
import, and suggest a #include more often in language modes where there
is no import syntax. Generally, if the target is in a header with
include guards or #pragma once, we should suggest either #including or
importing that header, and not importing a module that happens to
textually include it.

In passing, improve the notes we attach to the corresponding
diagnostics: calling an entity that we couldn't see "previous" is
confusing.
2020-04-28 18:41:14 -07:00
Richard Smith bb750689d5 C++ DR2387: a variable template declared wtih (or instantiated with) a
const-qualified type is not implicitly given internal linkage. But a
variable template declared 'static' is.

This reinstates part of r359048, reverted in r359076.

llvm-svn: 359260
2019-04-26 01:51:08 +00:00
Ilya Biryukov b8292c955c Revert r359048: C++ DR2387: a variable template declared wthi
The change breaks libc++ with the follwing error:

In file included from valarray:4:
.../include/c++/v1/valarray:1062:60: error: explicit instantiation declaration of 'valarray<_Tp>' with internal linkage
_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS valarray<size_t>::valarray(size_t))
                                                           ^
.../include/c++/v1/valarray:1063:60: error: explicit instantiation declaration of '~valarray<_Tp>' with internal linkage
_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS valarray<size_t>::~valarray())

llvm-svn: 359076
2019-04-24 08:50:24 +00:00
Richard Smith 3ac3e9ce04 Add missing diagnostic for anonymous struct/union definitions that don't
introduce any names.

llvm-svn: 359051
2019-04-24 00:08:02 +00:00
Richard Smith eeab4518e1 C++ DR2387: a variable template declared wtih (or instantiated with) a
const-qualified type is not implicitly given internal linkage. But a
variable template declared 'static' is.

llvm-svn: 359048
2019-04-23 23:48:00 +00:00
Richard Smith e181de7f4f [c++2a] Implement semantic restrictions for 'export' declarations.
llvm-svn: 358932
2019-04-22 22:50:11 +00:00
Richard Smith a5bbbfef15 [c++2a] Add semantic support for private module fragments.
llvm-svn: 358713
2019-04-18 21:12:54 +00:00
Richard Smith b1b580e047 [c++20] Enable driver and frontend support for building and using
modules when -std=c++2a is specified.

llvm-svn: 358355
2019-04-14 11:11:37 +00:00
Richard Smith d652bdd05f [c++20] Parsing support for module-declarations, import-declarations,
and the global and private module fragment.

For now, the private module fragment introducer is ignored, but use of
the global module fragment introducer should be properly enforced.

llvm-svn: 358353
2019-04-14 08:06:59 +00:00