Boost C++ Libraries: Ticket #10295: Boost Type Erasure does't compile on Visual Studio 2013

miticodonati@… — Sun, 03 Aug 2014 12:00:24 GMT

Even the most trivial example of usage doesn't compile:

http://www.boost.org/doc/libs/1_56_0_b1/libs/type_erasure/example/basic.cpp

The error is "unkown identifier: type" or something like that, and is present in various headers when calling something like "typedef typename ::boost::type_erasure::detail::" .. and obtatining the type via "::type". There may be also other problems

I would gladly help if possible, the library seems good

EDIT: Adding #define BOOST_NO_CXX11_VARIADIC_TEMPLATES seems to solve the issue

burkhard.daniel@… — Tue, 26 Aug 2014 16:17:55 GMT

I'm having the same problem. The workaround with BOOST_NO_CXX11_VARIADIC_TEMPLATES is ok-ish, but I'd rather see this work out of the box. Isn't MSVC2013 supposed to fully support variadic templates?

Steven Watanabe — Fri, 27 Feb 2015 22:43:46 GMT

Support for variadic templates in VS2013 is very buggy. I did fix this, but it appears that I failed to push the merge to master.

attachment set

Sun, 10 May 2015 12:05:19 GMT

attachment → type_erasure.patch

type_erasure patch for VS2013 (boost 1.58)

attachment set

Sun, 10 May 2015 12:08:24 GMT

attachment → type_erasure.2.patch

type_erasure patch for VS2013 (boost 1.58)

Sun, 10 May 2015 12:49:22 GMT

I've managed to patch the library for VS2013 to bring back support for variadic templates. Almost all examples and tests build successfully - except for:

printf.cpp example - asserts that any_printable needs the relaxed concept (I believe it is a bug in the example)
test_free.cpp - this test fails to build. VS2013 compiler seems to require that all overloaded declarations of injected free functions are seen before the first instantiation. Therefore when all the BOOST_TYPE_ERASURE_FREE(...) lines are moved above all the test cases, the test runs ok.

The patched callable.hpp also fixes overloaded callable concepts (multifunction.cpp example) which failed to built in VS2013. A bug in the compiler causes ambiguities between the overloaded function call operators imported via using declarations.

Sorry for double post of the attachment, the upload seemed stuck and the file didn't appear so I tried it again...

status changed; resolution set

Steven Watanabe — Sat, 13 Feb 2016 21:05:28 GMT

status new → closed
resolution → fixed