llvm-project/clang
Matthias Gehre 01a6338180 Add [[clang::suppress(rule, ...)]] attribute
Summary:
This patch implements parsing of [[clang::suppress(rule, ...)]]
and [[gsl::suppress(rule, ...)]] attributes.

C++ Core Guidelines depend heavily on tool support for
rule enforcement. They also propose a way to suppress
warnings [1] which is by annotating any ancestor in AST
with the C++11 attribute [[gsl::suppress(rule1,...)]].
To have a mechanism to suppress non-C++ Core
Guidelines specific, an additional spelling of [[clang::suppress]]
is defined.

For example, to suppress the warning cppcoreguidelines-slicing,
one could do
```
[[clang::suppress("cppcoreguidelines-slicing")]]
void f() { ... code that does slicing ... }
```
or
```
void g() {
  Derived b;
  [[clang::suppress("cppcoreguidelines-slicing")]]
  Base a{b};
  [[clang::suppress("cppcoreguidelines-slicing")]] {
    doSomething();
    Base a2{b};
  }
}
```

This parsing can then be used by clang-tidy, which includes multiple
C++ Core Guidelines rules, to suppress warnings (see
https://reviews.llvm.org/D24888).
For the exact naming of the rule in the attribute, there
are different possibilities, which will be defined in the
corresponding clang-tidy patch.

Currently, clang-tidy supports suppressing of warnings through "//
NOLINT" comments. There are some advantages that the attribute has:
- Suppressing specific warnings instead of all warnings
- Suppressing warnings in a block (namespace, function, compound
  statement)
- Code formatting may split a statement into multiple lines,
  thus a "// NOLINT" comment may be on the wrong line

I'm looking forward to your comments!

[1] https://github.com/isocpp/CppCoreGuidelines/blob/master/CppCoreGuidelines.md#inforce-enforcement

Reviewers: alexfh, aaron.ballman, rsmith

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D24886

llvm-svn: 298880
2017-03-27 19:45:24 +00:00
..
INPUTS
bindings [libclang] [OpenCL] Expose half type. 2017-02-10 15:51:11 +00:00
cmake [CMake] fix CLANG_INCLUDE_DIRS CMake export 2017-03-21 19:17:53 +00:00
docs Add LibreOffice Clang plugin to ExternalClangExamples.rst 2017-03-22 08:45:49 +00:00
examples Add LLVMOption to clang-interpreter, corresponding to r291938. 2017-01-14 08:54:05 +00:00
include Add [[clang::suppress(rule, ...)]] attribute 2017-03-27 19:45:24 +00:00
lib Add [[clang::suppress(rule, ...)]] attribute 2017-03-27 19:45:24 +00:00
runtime [sanitizer] Passthrough CMAKE_OSX_DEPLOYMENT_TARGET and CMAKE_OSX_SYSROOT when building compiler-rt from clang/runtime/CMakeLists.txt 2016-12-15 23:20:54 +00:00
test Add [[clang::suppress(rule, ...)]] attribute 2017-03-27 19:45:24 +00:00
tools [libclang] Bury dead TemporaryFiles 2017-03-24 09:49:54 +00:00
unittests Fix issues in clang-format's AlignConsecutive modes. 2017-03-23 02:51:25 +00:00
utils Correct class-template deprecation behavior-REDUX 2017-03-23 18:51:54 +00:00
www Implement DR 373 "Lookup on namespace qualified name in using-directive" 2017-03-17 21:41:20 +00:00
.arcconfig
.clang-format
.clang-tidy
.gitignore
CMakeLists.txt Define LLVM_ENABLE_WARNINGS when building standalone clang to ensure warnings get enabled 2017-03-07 00:15:18 +00:00
CODE_OWNERS.TXT
INSTALL.txt
LICENSE.TXT
ModuleInfo.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 development mailing list:
  http://lists.llvm.org/mailman/listinfo/cfe-dev

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