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Dan Liew cef6387e52 [Bounds-Safety] Temporarily relax a counted_by attribute restriction on flexible array members

In 0ec3b972e58bcbcdc1bebe1696ea37f2931287c3 an additional restriction
was added when applying the `counted_by` attribute to flexible array
members in structs. The restriction prevented the element type being
a struct that itself had a flexible array member. E.g.:

```
struct has_unannotated_VLA {
  int count;
  char buffer[];
};

struct buffer_of_structs_with_unnannotated_vla {
  int count;
  struct has_unannotated_VLA Arr[] __counted_by(count);
};
```

In this example assuming the size of `Arr` is `sizeof(struct
has_unannotated_VLA)*count` (which is what the attribute says) is wrong
because it doesn't account for the size of
`has_unannotated_VLA::buffer`. This is why this kind of code construct
was treated as an error.

However, it turns out existing Linux kernel code used the attribute
on a flexible array member in this way
(https://github.com/llvm/llvm-project/pull/90786#issuecomment-2118416515).

To unbreak the build this restriction is downgraded to a warning with
the plan to make it an error again once the errornous use of the
attribute in the Linux kernel is resolved.

2024-05-17 16:23:24 -07:00

bindings

…

cmake

[HLSL][CMake] Add clangd and distribution settings (#92011 )

2024-05-17 09:10:27 -05:00

docs

[BoundsSafety] Allow 'counted_by' attribute on pointers in structs in C (#90786 )

2024-05-17 12:07:40 -07:00

examples

…

include

[Bounds-Safety] Temporarily relax a counted_by attribute restriction on flexible array members

2024-05-17 16:23:24 -07:00

lib

[Bounds-Safety] Temporarily relax a counted_by attribute restriction on flexible array members

2024-05-17 16:23:24 -07:00

runtime

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test

[Bounds-Safety] Temporarily relax a counted_by attribute restriction on flexible array members

2024-05-17 16:23:24 -07:00

tools

[clang-fuzzer-dictionary] Skip EmptySpellingName after #89358

2024-05-16 11:53:15 -07:00

unittests

[clang-query] Remove support for srcloc output (#92442 )

2024-05-17 08:06:46 -04:00

utils

Allow passing creduce options through creduce-clang-crash.py (#92141 )

2024-05-14 14:40:33 -04:00

www

[clang] Implement CWG2428 "Deprecating a concept" (#92295 )

2024-05-17 16:02:44 +04:00

.clang-format

…

.clang-tidy

…

.gitignore

…

CMakeLists.txt

Use cmake to find perl executable (#91275 )

2024-05-08 07:35:47 -07:00

CodeOwners.rst

…

INSTALL.txt

…

LICENSE.TXT

…

NOTES.txt

…

README.txt

…

README.txt

//===----------------------------------------------------------------------===//
// C Language Family Front-end
//===----------------------------------------------------------------------===//

Welcome to Clang.  This is a compiler front-end for the C family of languages
(C, C++, Objective-C, and Objective-C++) which is built as part of the LLVM
compiler infrastructure project.

Unlike many other compiler frontends, Clang is useful for a number of things
beyond just compiling code: we intend for Clang to be host to a number of
different source-level tools.  One example of this is the Clang Static Analyzer.

If you're interested in more (including how to build Clang) it is best to read
the relevant web sites.  Here are some pointers:

Information on Clang:             http://clang.llvm.org/
Building and using Clang:         http://clang.llvm.org/get_started.html
Clang Static Analyzer:            http://clang-analyzer.llvm.org/
Information on the LLVM project:  http://llvm.org/

If you have questions or comments about Clang, a great place to discuss them is
on the Clang forums:
  https://discourse.llvm.org/c/clang/

If you find a bug in Clang, please file it in the LLVM bug tracker:
  http://llvm.org/bugs/