llvm-project/clang
Raphael Isemann ccfab8e459 [ObjC][DWARF] Emit DW_AT_APPLE_objc_direct for methods marked as __attribute__((objc_direct))
Summary:
With DWARF5 it is no longer possible to distinguish normal methods and methods with `__attribute__((objc_direct))` by just looking at the debug information
as they are both now children of the of the DW_TAG_structure_type that defines them (before only the `__attribute__((objc_direct))` methods were children).

This means that in LLDB we are no longer able to create a correct Clang AST of a module by just looking at the debug information. Instead we would
need to call the Objective-C runtime to see which of the methods have a `__attribute__((objc_direct))` and then add the attribute to our own Clang AST
depending on what the runtime returns. This would mean that we either let the module AST be dependent on the Objective-C runtime (which doesn't
seem right) or we retroactively add the missing attribute to the imported AST in our expressions.

A third option is to annotate methods with `__attribute__((objc_direct))` as `DW_AT_APPLE_objc_direct` which is what this patch implements. This way
LLDB doesn't have to call the runtime for any `__attribute__((objc_direct))` method and the AST in our module will already be correct when we create it.

Reviewers: aprantl, SouraVX

Reviewed By: aprantl

Subscribers: hiraditya, cfe-commits, llvm-commits

Tags: #clang, #llvm, #debug-info

Differential Revision: https://reviews.llvm.org/D71201
2019-12-17 09:40:36 +01:00
..
INPUTS
bindings [AIX] Disable clang python binding tests 2019-11-26 15:30:38 -05:00
cmake Always -I clang/include when tblgen'ing in Clang. 2019-12-16 13:33:59 -05:00
docs [OPENMP][DOCS]Claim simd nontemporal clause, NFC. 2019-12-16 13:38:58 -05:00
examples [Attr] Add missing header for clang example. 2019-12-09 12:50:05 +00:00
include Check whether the destination is a complete type in a static_cast (or 2019-12-16 18:33:35 -08:00
lib [ObjC][DWARF] Emit DW_AT_APPLE_objc_direct for methods marked as __attribute__((objc_direct)) 2019-12-17 09:40:36 +01:00
runtime
test [ObjC][DWARF] Emit DW_AT_APPLE_objc_direct for methods marked as __attribute__((objc_direct)) 2019-12-17 09:40:36 +01:00
tools [NFC] Fix typos in Clangd and Clang 2019-12-16 10:54:40 +01:00
unittests [NFC] Fix typos in Clangd and Clang 2019-12-16 10:54:40 +01:00
utils Forward {read,write}SomeEnumType to {read,write}Enum instead of 2019-12-16 13:34:00 -05:00
www [c++20] P1959R0: Remove support for std::*_equality. 2019-12-16 17:49:45 -08:00
.arcconfig
.clang-format
.clang-tidy
.gitignore
CMakeLists.txt [clang] Move CLANG_BOOTSTRAP_CMAKE_ARGS above PASSTHROUGH_VARIABLES 2019-12-13 19:05:04 -08:00
CODE_OWNERS.TXT
INSTALL.txt
LICENSE.TXT
ModuleInfo.txt
NOTES.txt
README.txt Revert "test commit" 2019-11-08 14:09:09 +01:00

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/