Commit Graph

26 Commits

Author SHA1 Message Date
Martin Boehme 8c7b64b5ae [clang] Reject non-declaration C++11 attributes on declarations
For backwards compatiblity, we emit only a warning instead of an error if the
attribute is one of the existing type attributes that we have historically
allowed to "slide" to the `DeclSpec` just as if it had been specified in GNU
syntax. (We will call these "legacy type attributes" below.)

The high-level changes that achieve this are:

- We introduce a new field `Declarator::DeclarationAttrs` (with appropriate
  accessors) to store C++11 attributes occurring in the attribute-specifier-seq
  at the beginning of a simple-declaration (and other similar declarations).
  Previously, these attributes were placed on the `DeclSpec`, which made it
  impossible to reconstruct later on whether the attributes had in fact been
  placed on the decl-specifier-seq or ahead of the declaration.

- In the parser, we propgate declaration attributes and decl-specifier-seq
  attributes separately until we can place them in
  `Declarator::DeclarationAttrs` or `DeclSpec::Attrs`, respectively.

- In `ProcessDeclAttributes()`, in addition to processing declarator attributes,
  we now also process the attributes from `Declarator::DeclarationAttrs` (except
  if they are legacy type attributes).

- In `ConvertDeclSpecToType()`, in addition to processing `DeclSpec` attributes,
  we also process any legacy type attributes that occur in
  `Declarator::DeclarationAttrs` (and emit a warning).

- We make `ProcessDeclAttribute` emit an error if it sees any non-declaration
  attributes in C++11 syntax, except in the following cases:
  - If it is being called for attributes on a `DeclSpec` or `DeclaratorChunk`
  - If the attribute is a legacy type attribute (in which case we only emit
    a warning)

The standard justifies treating attributes at the beginning of a
simple-declaration and attributes after a declarator-id the same. Here are some
relevant parts of the standard:

- The attribute-specifier-seq at the beginning of a simple-declaration
  "appertains to each of the entities declared by the declarators of the
  init-declarator-list" (https://eel.is/c++draft/dcl.dcl#dcl.pre-3)

- "In the declaration for an entity, attributes appertaining to that entity can
  appear at the start of the declaration and after the declarator-id for that
  declaration." (https://eel.is/c++draft/dcl.dcl#dcl.pre-note-2)

- "The optional attribute-specifier-seq following a declarator-id appertains to
  the entity that is declared."
  (https://eel.is/c++draft/dcl.dcl#dcl.meaning.general-1)

The standard contains similar wording to that for a simple-declaration in other
similar types of declarations, for example:

- "The optional attribute-specifier-seq in a parameter-declaration appertains to
  the parameter." (https://eel.is/c++draft/dcl.fct#3)

- "The optional attribute-specifier-seq in an exception-declaration appertains
  to the parameter of the catch clause" (https://eel.is/c++draft/except.pre#1)

The new behavior is tested both on the newly added type attribute
`annotate_type`, for which we emit errors, and for the legacy type attribute
`address_space` (chosen somewhat randomly from the various legacy type
attributes), for which we emit warnings.

Depends On D111548

Reviewed By: aaron.ballman, rsmith

Differential Revision: https://reviews.llvm.org/D126061
2022-06-15 11:58:26 +02:00
Aaron Ballman 4be105c98a Silence some false positive -Wstrict-prototype warnings
Before issuing the warning about use of a strict prototype, check if
the declarator is required to have a prototype through some other means
determined at parse time.

This silences false positives in OpenCL code (where the functions are
forced to have a prototype) and block literal expressions.
2022-05-13 08:31:52 -04:00
Aaron Ballman 11da1b53d8 [C89/C2x] Improve diagnostics around strict prototypes in C
Functions without prototypes in C (also known as K&R C functions) were
introduced into C89 as a deprecated feature and C2x is now reclaiming
that syntax space with different semantics. However, Clang's
-Wstrict-prototypes diagnostic is off-by-default (even in pedantic
mode) and does not suffice to warn users about issues in their code.

This patch changes the behavior of -Wstrict-prototypes to only diagnose
declarations and definitions which are not going to change behavior in
C2x mode, and enables the diagnostic in -pedantic mode. The diagnostic
is now specifically about the fact that the feature is deprecated.

It also adds -Wdeprecated-non-prototype, which is grouped under
-Wstrict-prototypes and diagnoses declarations or definitions which
will change behavior in C2x mode. This diagnostic is enabled by default
because the risk is higher for the user to continue to use the
deprecated feature.

Differential Revision: https://reviews.llvm.org/D122895
2022-04-08 16:19:58 -04:00
Timm Bäder 711e3a5691 [clang][parse] Move source range into ParsedAttibutesView
Move the SourceRange from the old ParsedAttributesWithRange into
ParsedAttributesView, so we have source range information available
everywhere we use attributes.

This also removes ParsedAttributesWithRange (replaced by simply using
ParsedAttributes) and ParsedAttributesVieWithRange (replaced by using
ParsedAttributesView).

Differential Revision: https://reviews.llvm.org/D121201
2022-03-24 08:11:57 +01:00
Justas Janickas cc9260a0fb [OpenCL] Supports optional generic address space semantics in C++ for OpenCL 2021
Adds support for a feature macro `__opencl_c_generic_adress_space`
in C++ for OpenCL 2021 enabling a respective optional core feature
from OpenCL 3.0. Testing is only performed in SemaOpenCL because
generic address space functionality is yet to be implemented in
C++ for OpenCL 2021.

This change aims to achieve compatibility between C++ for OpenCL
2021 and OpenCL 3.0.

Differential Revision: https://reviews.llvm.org/D108461
2021-09-06 10:20:38 +01:00
Anton Zabaznov 78463ebde2 [OpenCL] Add support of __opencl_c_generic_address_space feature macro
Reviewed By: Anastasia

Differential Revision: https://reviews.llvm.org/D103401
2021-07-13 13:14:10 +03:00
Aaron Ballman 9f2c7effd7 Parse different attribute syntaxes in arbitrary order
In Clang today, we parse the different attribute syntaxes
(__attribute__, __declspec, and [[]]) in a fairly rigid order. This
leads to confusion for users when they guess the order incorrectly,
and leads to bug reports like PR24559 or necessitates changes like
D94788.

This patch adds a helper function to allow us to more easily parse
attributes in arbitrary order, and then updates all of the places
where we would parse two or more different syntaxes in a rigid order to
use the helper method. The patch does not attempt to handle Microsoft
attributes ([]) because those are ambiguous with other code constructs
and we don't have any attributes that use the syntax.
2021-01-27 15:30:15 -05:00
Richard Smith 6781fee085 Don't permit array bound constant folding in OpenCL.
Permitting non-standards-driven "do the best you can" constant-folding
of array bounds is permitted solely as a GNU compatibility feature. We
should not be doing it in any language mode that is attempting to be
conforming.

From https://reviews.llvm.org/D20090 it appears the intent here was to
permit `__constant int` globals to be used in array bounds, but the
change in that patch only added half of the functionality necessary to
support that in the constant evaluator. This patch adds the other half
of the functionality and turns off constant folding for array bounds in
OpenCL.

I couldn't find any spec justification for accepting the kinds of cases
that D20090 accepts, so a reference to where in the OpenCL specification
this is permitted would be useful.

Note that this change also affects the code generation in one test:
because after 'const int n = 0' we now treat 'n' as a constant
expression with value 0, it's now a null pointer, so '(local int *)n'
forms a null pointer rather than a zero pointer.

Reviewed By: Anastasia

Differential Revision: https://reviews.llvm.org/D89520
2020-10-20 16:52:28 -07:00
Anastasia Stulova fa755d3e71 [Sema][C++] Propagate conversion kind to specialize the diagnostics
Compute and propagate conversion kind to diagnostics helper in C++
to provide more specific diagnostics about incorrect implicit
conversions in assignments, initializations, params, etc...

Duplicated some diagnostics as errors because C++ is more strict.

Tags: #clang

Differential Revision: https://reviews.llvm.org/D74116
2020-02-25 16:05:37 +00:00
Anastasia Stulova 6064f426a1 [OpenCL] Restrict addr space conversions in nested pointers
Address space conversion changes pointer representation.
This commit disallows such conversions when they are not
legal i.e. for the nested pointers even with compatible
address spaces. Because the address space conversion in
the nested levels can't be generated to modify the pointers
correctly. The behavior implemented is as follows:

- Any implicit conversions of nested pointers with different
  address spaces is rejected.
- Any conversion of address spaces in nested pointers in safe
  casts (e.g. const_cast or static_cast) is rejected.
- Conversion in low level C-style or reinterpret_cast is accepted
  but with a warning (this aligns with OpenCL C behavior).

Fixes PR39674

Differential Revision: https://reviews.llvm.org/D73360
2020-02-07 12:04:35 +00:00
Anastasia Stulova 869d17d851 [OpenCL] Pretty print __private addr space
Add printing of __private address space to TypePrinter to allow
it appears in diagnostics and AST dumps as all other language
addr spaces.

Tags: #clang

Differential Revision: https://reviews.llvm.org/D71272
2019-12-27 13:42:07 +00:00
Victor Lomuller 11a9bae8f6 [AST] Enable expression of OpenCL language address spaces an attribute
Summary:
Enable a way to set OpenCL language address space using attributes
in addition to existing keywords.

Signed-off-by: Victor Lomuller victor@codeplay.com

Reviewers: aaron.ballman, Anastasia

Subscribers: yaxunl, ebevhan, cfe-commits, Naghasan

Tags: #clang

Differential Revision: https://reviews.llvm.org/D71005

Signed-off-by: Alexey Bader <alexey.bader@intel.com>
2019-12-05 12:24:06 +03:00
Michael Liao fa9dd410a9 [opencl] Fix address space deduction on array variables.
Summary:

- The deduced address space needs applying to its element type as well.

Reviewers: Anastasia

Subscribers: yaxunl, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D70981
2019-12-04 09:37:50 -05:00
Anastasia Stulova 88ed70e247 [OpenCL] Rename lang mode flag for C++ mode
Rename lang mode flag to -cl-std=clc++/-cl-std=CLC++
or -std=clc++/-std=CLC++.

This aligns with OpenCL C conversion and removes ambiguity
with OpenCL C++. 

Differential Revision: https://reviews.llvm.org/D65102

llvm-svn: 367008
2019-07-25 11:04:29 +00:00
Anastasia Stulova 5b6dda33d1 [Sema][OpenCL] Make address space conversions a bit stricter.
The semantics for converting nested pointers between address
spaces are not very well defined. Some conversions which do not
really carry any meaning only produce warnings, and in some cases
warnings hide invalid conversions, such as 'global int*' to
'local float*'!

This patch changes the logic in checkPointerTypesForAssignment
and checkAddressSpaceCast to fail properly on implicit conversions
that should definitely not be permitted. We also dig deeper into the
pointer types and warn on explicit conversions where the address
space in a nested pointer changes, regardless of whether the address
space is compatible with the corresponding pointer nesting level
on the destination type.

Fixes PR39674!

Patch by ebevhan (Bevin Hansson)!

Differential Revision: https://reviews.llvm.org/D58236

llvm-svn: 360258
2019-05-08 14:23:49 +00:00
Anastasia Stulova 6f7c536e08 [Sema] Change addr space diagnostics in casts to follow C++ style.
This change adds a new diagnostic for mismatching address spaces
to be used for C++ casts (only enabled in C style cast for now,
the rest will follow!).

The change extends C-style cast rules to account for address spaces.
It also adds a separate function for address space cast checking that
can be used to map from a separate address space cast operator
addrspace_cast (to be added as a follow up patch).

Note, that after this change clang will no longer allows arbitrary
address space conversions in reinterpret_casts because they can lead
to accidental errors. The implicit safe conversions would still be
allowed.

Differential Revision: https://reviews.llvm.org/D58346

llvm-svn: 355609
2019-03-07 17:06:30 +00:00
Anastasia Stulova 5325f83470 [OpenCL] Fixed address space cast in C style cast of C++ parsing
C style cast in OpenCL C++ was ignoring the address space
conversions from OpenCL C and as a result accepting incorrect
code to compile. This commit adds special function for checking 
correctness of address spaces that is shared between C and C++
casts.
 

llvm-svn: 344148
2018-10-10 16:05:22 +00:00
Michael Kruse dc5ce72afa Append new attributes to the end of an AttributeList.
Recommit of r335084 after revert in r335516.

... instead of prepending it at the beginning (the original behavior
since implemented in r122535 2010-12-23). This builds up an
AttributeList in the the order in which the attributes appear in the
source.

The reverse order caused nodes for attributes in the AST (e.g. LoopHint)
to be in the reverse order, and therefore printed in the wrong order in
-ast-dump. Some TODO comments mention this. The order was explicitly
reversed for enable_if attribute overload resolution and name mangling,
which is not necessary anymore with this patch.

The change unfortunately has some secondary effect, especially on
diagnostic output. In the simplest cases, the CHECK lines or expected
diagnostic were changed to the the new output. If the kind of
error/warning changed, the attributes' order was changed instead.

This unfortunately causes some 'previous occurrence here' hints to be
textually after the main marker. This typically happens when attributes
are merged, but are incompatible to each other. Interchanging the role
of the the main and note SourceLocation will also cause the case where
two different declaration's attributes (in contrast to multiple
attributes of the same declaration) are merged to be reverse. There is
no easy fix because sometimes previous attributes are merged into a new
declaration's attribute list, sometimes new attributes are added to a
previous declaration's attribute list. Since 'previous occurrence here'
pointing to locations after the main marker is not rare, I left the
markers as-is; it is only relevant when the attributes are declared in
the same declaration anyway.

Differential Revision: https://reviews.llvm.org/D48100

llvm-svn: 338800
2018-08-03 01:21:16 +00:00
Michael Kruse 41dd6ced2c Revert "Append new attributes to the end of an AttributeList."
This reverts commit r335084 as requested by David Jones and
Eric Christopher because of differences of emitted warnings.

llvm-svn: 335516
2018-06-25 20:06:13 +00:00
Anastasia Stulova 7f785bb458 [OpenCL] Fixed parsing of address spaces for C++.
Added address space tokens to C++ parsing code to be able
to parse declarations that start from an address space keyword.

llvm-svn: 335362
2018-06-22 16:20:21 +00:00
Alexey Bader f29d777f84 [Sema] Allow creating types with multiple of the same addrspace.
Summary:
The comment with the OpenCL clause about this clearly
says: "No type shall be qualified by qualifiers for
two or more different address spaces."

This must mean that two or more qualifiers for the
_same_ address space is allowed. However, it is
likely unintended by the programmer, so emit a
warning.

For dependent address space types, reject them like
before since we cannot know what the address space
will be.

Patch by Bevin Hansson (ebevhan).

Reviewers: Anastasia

Reviewed By: Anastasia

Subscribers: bader, cfe-commits

Differential Revision: https://reviews.llvm.org/D47630

llvm-svn: 335103
2018-06-20 08:31:24 +00:00
Michael Kruse ea31f0e4b8 Append new attributes to the end of an AttributeList.
... instead of prepending it at the beginning (the original behavior
since implemented in r122535 2010-12-23). This builds up an
AttributeList in the the order in which the attributes appear in the
source.

The reverse order caused nodes for attributes in the AST (e.g. LoopHint)
to be in the reverse, and therefore printed in the wrong order by
-ast-dump. Some TODO comments mention this. The order was explicitly
reversed for enable_if attribute overload resolution and name mangling,
which is not necessary anymore with this patch.

The change unfortunately has some secondary effects, especially for
diagnostic output. In the simplest cases, the CHECK lines or expected
diagnostic were changed to the the new output. If the kind of
error/warning changed, the attribute's order was changed instead.

It also causes some 'previous occurrence here' hints to be textually
after the main marker. This typically happens when attributes are
merged, but are incompatible. Interchanging the role of the the main
and note SourceLocation will also cause the case where two different
declaration's attributes (in contrast to multiple attributes of the
same declaration) are merged to be reversed. There is no easy fix
because sometimes previous attributes are merged into a new
declaration's attribute list, sometimes new attributes are added to a
previous declaration's attribute list. Since 'previous occurrence here'
pointing to locations after the main marker is not rare, I left the
markers as-is; it is only relevant when the attributes are declared in
the same declaration anyway, which often is on the same line.

Differential Revision: https://reviews.llvm.org/D48100

llvm-svn: 335084
2018-06-19 23:46:52 +00:00
Yaxun Liu b7318e02c1 [OpenCL] Add LangAS::opencl_private to represent private address space in AST
Currently Clang uses default address space (0) to represent private address space for OpenCL
in AST. There are two issues with this:

Multiple address spaces including private address space cannot be diagnosed.
There is no mangling for default address space. For example, if private int* is emitted as
i32 addrspace(5)* in IR. It is supposed to be mangled as PUAS5i but it is mangled as
Pi instead.

This patch attempts to represent OpenCL private address space explicitly in AST. It adds
a new enum LangAS::opencl_private and adds it to the variable types which are implicitly
private:

automatic variables without address space qualifier

function parameter

pointee type without address space qualifier (OpenCL 1.2 and below)

Differential Revision: https://reviews.llvm.org/D35082

llvm-svn: 315668
2017-10-13 03:37:48 +00:00
Tom Stellard ade13b2a4e OpenCL: Emit global variables in the constant addr space as constant globals
llvm-svn: 219929
2014-10-16 15:29:19 +00:00
Joey Gouly 8fc32f01dc [OpenCL] Disallow casts between address spaces.
llvm-svn: 199208
2014-01-14 12:47:29 +00:00
Peter Collingbourne 5ad3ebaefd TypePrinter: print OpenCL address space names. Patch by Richard
Membarth, test case by myself.

llvm-svn: 144063
2011-11-08 02:52:58 +00:00