Commit Graph

29 Commits

Author SHA1 Message Date
Hans Wennborg 5869ec4c6c MS ABI: Don't allow dllexport/import on lambdas
This is to follow up on David's comment in
http://reviews.llvm.org/D12422#235509

llvm-svn: 247718
2015-09-15 21:05:30 +00:00
Hans Wennborg 5427a69545 Don't allow dllexport/import on static local variables
They might technically have external linkage, but it still doesn't make sense
for the user to try and export such variables. This matches MSVC's and MinGW's
behaviour.

llvm-svn: 246864
2015-09-04 19:59:39 +00:00
Hans Wennborg 6eaa8323a8 Allow TLS vars in dllimport/export functions; only inline dllimport functions when safe (PR24593)
This patch does two things:

1) Don't error about dllimport/export on thread-local static local variables.
   We put those attributes on static locals in dllimport/export functions
   implicitly in case the function gets inlined. Now, for TLS variables this
   is a problem because we can't import such variables, but it's a benign
   problem becase:

2) Make sure we never inline a dllimport function TLS static locals. In fact,
   never inline a dllimport function that references a non-imported function
   or variable (because these are not defined in the importing library). This
   seems to match MSVC's behaviour.

Differential Revision: http://reviews.llvm.org/D12422

llvm-svn: 246338
2015-08-28 21:47:01 +00:00
Hans Wennborg bb1983cf3a Enable propagation of dll attributes to previously instantiated base class templates in some cases
It is safe to add a dll attribute if the base class template previously only had
an explicit instantiation declaration, or was implicitly instantiated.

I both those cases, the members would not have been codegenned yet. In the case
of explicit instantiation declaration this is natural, and for implicit
instantiations, codegen is deferred (see r225570).

This is work towards fixing PR23770.

llvm-svn: 239373
2015-06-09 00:39:03 +00:00
Hans Wennborg 29b7a93935 Narrow the -Wunsupported-dll-base-class-template warning.
Don't warn about not being able to propagate dll attribute to a base class template
when that base already has a different attribute.

MSVC doesn't actually try to do this; the first attribute that was propagated
takes precedence, so Clang is already doing the right thing and there's no
need to warn.

(This is a step towards fixing PR21718.)

llvm-svn: 239372
2015-06-09 00:38:56 +00:00
Aaron Ballman 674cf26892 __declspec is not a core Clang language extension. Instead, require -fms-extensions or -fborland to enable the language extension.
Note: __declspec is also temporarily enabled when compiling for a CUDA target because there are implementation details relying on __declspec(property) support currently. When those details change, __declspec should be disabled for CUDA targets.
llvm-svn: 238238
2015-05-26 19:44:52 +00:00
Hans Wennborg 287231cb7a Don't dllimport/export class members with internal linkage (PR23308)
For example, a function taking a parameter with internal linkage will
itself have internal linkage since it cannot be called outside the
translation unit.

Differential Revision: http://reviews.llvm.org/D9182

llvm-svn: 235471
2015-04-22 04:05:17 +00:00
Hans Wennborg fd76d91366 Warn about dllexported explicit class template instantiation declarations (PR22035)
Clang would previously become confused and crash here.

It does not make a lot of sense to export these, so warning seems appropriate.

MSVC will export some member functions for this kind of specializations, whereas
MinGW ignores the dllexport-edness. The latter behaviour seems better.

Differential Revision: http://reviews.llvm.org/D6984

llvm-svn: 226208
2015-01-15 21:18:30 +00:00
Hans Wennborg 8313c76836 Don't allow dllimport/export on classes with internal linkage (PR21399)
Trying to import or export such classes doesn't make sense, and Clang
would assert trying to export vtables for them.

This is consistent with how we treat functions with internal linkage,
but it is stricter than MSVC so we may have to back down if it breaks
real code.

llvm-svn: 221160
2014-11-03 16:09:16 +00:00
Hans Wennborg ac6073bb1f Follow-up to r216619: use isCXXCLassMember() instead of trying to
check the context ourselves when selectively allowing late-added
dll attributes on unused free functions and variables (PR20746)

llvm-svn: 220874
2014-10-29 21:20:57 +00:00
David Majnemer 5da21da4f6 MS ABI: Disallow dllimported/exported variables from having TLS
Windows TLS relies on indexing through a tls_index in order to get at
the DLL's thread local variables.  However, this index is not exported
along with the variable: it is assumed that all accesses to thread local
variables are inside the same module which created the variable in the
first place.

While there are several implementation techniques we could adopt to fix
this (notably, the Itanium ABI gets this for free), it is not worth the
heroics.

Instead, let's just ban this combination.  We could revisit this in the
future if we need to.

This fixes PR21111.

llvm-svn: 219049
2014-10-04 06:51:54 +00:00
Hans Wennborg dd96db2c03 Allow adding dll attributes on certain redecls with a warning if the decl hasn't been used yet (PR20746)
This shouldn't really be allowed, but it comes up in real code (see PR). As
long as the decl hasn't been used there's no technical difficulty in supporting
it, so downgrade the error to a warning.

Differential Revision: http://reviews.llvm.org/D5087

llvm-svn: 216619
2014-08-27 21:27:40 +00:00
Hans Wennborg 0dac192d77 Ignore -Wunsupported-dll-base-class-template by default
The situation it is warning about (see PR20725) is not very likely
to be a real problem, and it is unclear what action the user should take
if the warning does fire.

llvm-svn: 216283
2014-08-22 20:33:18 +00:00
Hans Wennborg 334e4ffc0d MS ABI: Don't always instantiate all members of dllexported class templates (PR20163)
Normally we mark all members of exported classes referenced to get them emitted.

However, MSVC doesn't do this for class templates that are implicitly specialized or
just have an explicit instantiation declaration. For such specializations, the members
are emitted when referenced.

The exception is the case when the dllexport attribute is propagated from a base class
to a base class template that doesn't have an explicit attribute: in this case all
methods of the base class template do get instantiated.

llvm-svn: 216145
2014-08-21 01:14:01 +00:00
Alp Toker cd3acb5604 Avoid non-attributive uses of 'unsupported' in diagnostics
We don't have a style guide for diagnostic messages, but convention strongly
favours the forms:

  'attribute is not supported', 'unsupported attribute'

We generally avoid:

  'attribute is unsupported', 'non-supported attribute'

llvm-svn: 212972
2014-07-14 19:16:22 +00:00
Hans Wennborg 9bea9cc73b MS ABI: Propagate class-level DLL attributes to class template specialization bases (PR11170)
Consider the following code:

  template <typename T> class Base {};
  class __declspec(dllexport) class Derived : public Base<int> {}

When the base of an exported or imported class is a class template
specialization, MSVC will propagate the dll attribute to the base.
In the example code, Base<int> becomes a dllexported class.

This commit makes Clang do the proopagation when the base hasn't been
instantiated yet, and warns about it being unsupported otherwise.
This is different from MSVC, which allows changing a specialization
back and forth between dllimport and dllexport and seems to let the
last one win. Changing the dll attribute after instantiation would be
hard for us, and doesn't seem to come up in practice, so I think this
is a reasonable limitation to have.

MinGW doesn't do this kind of propagation.

Differential Revision: http://reviews.llvm.org/D4264

llvm-svn: 211725
2014-06-25 18:25:57 +00:00
Hans Wennborg 5e64528195 MS ABI: Ignore dll attributes on partial template specializations
llvm-svn: 211648
2014-06-24 23:57:13 +00:00
Hans Wennborg 853ae94660 Start adding support for dllimport/dllexport on classes (PR11170)
This implements the central part of support for dllimport/dllexport on
classes: allowing the attribute on class declarations, inheriting it
to class members, and forcing emission of exported members. It's based
on Nico Rieck's patch from http://reviews.llvm.org/D1099.

This patch doesn't propagate dllexport to bases that are template
specializations, which is an interesting problem. It also doesn't
look at the rules when redeclaring classes with different attributes,
I'd like to do that separately.

Differential Revision: http://reviews.llvm.org/D3877

llvm-svn: 209908
2014-05-30 16:59:42 +00:00
Nico Rieck 9de0a57687 Sema: Functions with dll attributes cannot be deleted
llvm-svn: 209827
2014-05-29 16:51:19 +00:00
Nico Rieck 078d2f89cd Sema: Check dll attributes on static data members
Redeclarations cannot add a dll attribute and static data members cannot
be defined.

llvm-svn: 209825
2014-05-29 16:50:20 +00:00
Nico Rieck 68694b53ab Sema: Add dll attribute tests for member functions
llvm-svn: 209598
2014-05-25 10:35:03 +00:00
Nico Rieck 99f12ef44f Sema: Add dll attribute tests for variable templates
llvm-svn: 209597
2014-05-25 10:34:36 +00:00
Nico Rieck ffd8a3364c Sema: Add more tests for dll attributes on inline functions
llvm-svn: 209542
2014-05-23 19:07:49 +00:00
Hans Wennborg b0f2f146bb Allow dllimport/dllexport on inline functions and adjust the linkage.
This is a step towards handling these attributes on classes (PR11170).

Differential Revision: http://reviews.llvm.org/D3772

llvm-svn: 208925
2014-05-15 22:07:49 +00:00
David Blaikie bdb34beae0 Some more anonymous namespace diagnostics to switch to ()
llvm-svn: 205400
2014-04-02 06:18:49 +00:00
Nico Rieck 8ca0bfc57f Sema: Require external linkage for dll attributes
llvm-svn: 205198
2014-03-31 14:56:58 +00:00
Nico Rieck 82f0b06749 Sema: Check dll attributes on redeclarations
A redeclaration may not add dllimport or dllexport attributes. dllexport is
sticky and can be omitted on redeclarations while dllimport cannot.

llvm-svn: 205197
2014-03-31 14:56:15 +00:00
Nico Rieck 8e9791f62c Sema: Definition of dllimport globals is not allowed
Upgrades the warning to an error and clarifies the message by treating the
definition as error instead of the attribute.

llvm-svn: 202300
2014-02-26 21:27:13 +00:00
Nico Rieck 6047866232 Reorganize and improve semantic tests for dllexport/import
llvm-svn: 201947
2014-02-22 19:47:30 +00:00