[
https://issues.apache.org/jira/browse/AVRO-2598?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Marcel Pfütze updated AVRO-2598:
--------------------------------
Summary: C++ standard of library implies C++ standard of projects using
Avro (was: C++ standard of library defines C++ standard of projects using Avro)
> C++ standard of library implies C++ standard of projects using Avro
> -------------------------------------------------------------------
>
> Key: AVRO-2598
> URL: https://issues.apache.org/jira/browse/AVRO-2598
> Project: Apache Avro
> Issue Type: Bug
> Components: c++
> Affects Versions: 1.9.0, 1.9.1
> Reporter: Marcel Pfütze
> Priority: Major
>
> SInce Avro 1.9.0 there is an if macro in a lot of headers that uses the
> current C++ standard.
> If you build the library from source and use it in another project this can
> lead to segfaults.
> Example of macro:
> {code:c++}
> template<typename T> T& GenericDatum::value() {
> return (type_ == AVRO_UNION) ?
> #if __cplusplus >= 201703L
> std::any_cast<GenericUnion>(&value_)->datum().value<T>() :
> *std::any_cast<T>(&value_);
> #else
> boost::any_cast<GenericUnion>(&value_)->datum().value<T>() :
> *boost::any_cast<T>(&value_);
> #endif
> {code}
> In our case we build the library from source (which uses the c++11 by
> default) and used it in a project using C++17. There's very little indication
> to the user why this happens.
> My proposals:
> * Move implementation from header to source file so that the used standard
> is decided at build time.
> * Use the [CMAKE_CXX_STANDARD
> |https://cmake.org/cmake/help/v3.1/variable/CMAKE_CXX_STANDARD.html]
> functionality provided by cmake to set the standard. In this way the standard
> can also easily set when building the code without actually manipulating the
> CMakeLists.txt file. Of course the --std=c++11
> [here|https://github.com/apache/avro/blob/89218262cde62e98fcb3778b86cd3f03056c54f3/lang/c%2B%2B/CMakeLists.txt#L55]
> can be removed.
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
