LLVM 19 migration

[wbqpk3]

This patch implements LLVM 19, clang-19 support. The changes are not backwards compatible, meaning it no longer compiles with older LLVM.

Upgraded dependencies:

• Boost: version 1.86.0 (current Boost version 1.74.0 does not compile with clang-19)
• C++ standard upgraded to 17 (required by clang-19)

Prerequisites

The new Boost version is not in the Ubuntu 22.04 repositories, it needs to be compiled from source.
Download from https://www.boost.org/users/download/, steps:

./bootstrap.sh --prefix=path/to/installation/prefix
./b2 install

LLVM 19 is also not in the repositories.
Download from https://apt.llvm.org/, steps:

wget https://apt.llvm.org/llvm.sh
chmod +x llvm.sh
sudo ./llvm.sh 19 all

Compiling CodeCompass

Configure CMake with these flags:

-DLLVM_DIR=/usr/lib/llvm-19/cmake
-DClang_DIR=/usr/lib/cmake/clang-19 
-DCMAKE_C_COMPILER=clang-19 
-DCMAKE_CXX_COMPILER=clang++-19

We may encounter the following error:

In file included from CodeCompass/plugins/cpp/parser/src/cppparser.cpp:26:
In file included from CodeCompass/util/include/util/logutil.h:4:
In file included from /usr/local/include/boost/log/trivial.hpp:23:
In file included from /usr/local/include/boost/log/sources/severity_logger.hpp:23:
In file included from /usr/local/include/boost/log/sources/basic_logger.hpp:36:
In file included from /usr/local/include/boost/log/core/core.hpp:23:
In file included from /usr/local/include/boost/log/core/record.hpp:21:
In file included from /usr/local/include/boost/log/attributes/attribute_value_set.hpp:27:
In file included from /usr/local/include/boost/log/attributes/attribute_value.hpp:18:
In file included from /usr/local/include/boost/type_index.hpp:29:
In file included from /usr/local/include/boost/type_index/stl_type_index.hpp:34:
In file included from /usr/local/include/boost/core/demangle.hpp:32:
/usr/lib/llvm-19/include/cxxabi.h:55:1: error: functions that differ only in their return type cannot be overloaded
   50 | extern _LIBCXXABI_FUNC_VIS __cxa_exception*
      |                            ~~~~~~~~~~~~~~~~
   51 | #ifdef __wasm__
   52 | // In Wasm, a destructor returns its argument
   53 | __cxa_init_primary_exception(void* object, std::type_info* tinfo, void*(_LIBCXXABI_DTOR_FUNC* dest)(void*)) throw();
   54 | #else
   55 | __cxa_init_primary_exception(void* object, std::type_info* tinfo, void(_LIBCXXABI_DTOR_FUNC* dest)(void*)) throw();
      | ^
/usr/lib/gcc/x86_64-linux-gnu/11/../../../../include/c++/11/bits/cxxabi_init_exception.h:70:7: note: previous declaration is here
   69 |       __cxa_refcounted_exception*
      |       ~~~~~~~~~~~~~~~~~~~~~~~~~~~
   70 |       __cxa_init_primary_exception(void *object, std::type_info *tinfo,
      |       ^

This can be resolved by installing LLVM-18 removing the following packages:

sudo apt purge libc++1-19 libc++-19-dev libc++abi1-19 libc++abi-19-dev

Finally, CodeCompass should build without errors.
I also successfully parsed the gtest C++ project.