id	summary	reporter	owner	description	type	status	milestone	component	version	severity	resolution	keywords	cc
4351	boost 1_43_0 BOOST_MPL_ASSERT compile error (gcc 4.2)	Jeff Epler <jepler@…>	Joel Falcou	"The simple version:
{{{
#include <boost/mpl/assert.hpp>
int main() { BOOST_MPL_ASSERT((1)); BOOST_MPL_ASSERT((1)); return 0;}
}}}
(it is important that both BOOST_MPL_ASSERT invocations are '''on the same line''')

On gcc 4.2.4 (Ubuntu 8.04), this leads to the following error:
{{{
$ g++ -I /src/jepler/boost_1_43_0/ main.c
main.c: In function ‘int main()’:
main.c:2: error: conflicting declaration ‘mpl_assertion_in_line_2’
main.c:2: error: ‘mpl_assertion_in_line_2’ has a previous declaration
 as ‘main()::<anonymous enum> mpl_assertion_in_line_2’
}}}

I am trying to migrate an application from boost 1_34_0 to boost 1_43_0.  Among other boost features, it uses boost serialization.  It has BOOST_CLASS_VERSION declarations across various header files.  When two header files are included in the same source file, and they both contain BOOST_CLASS_VERSION declarations '''on the same source line''' (e.g., fooclass.h line 30 and barclass.h line 30) a similar error results.

The attached tar file demonstrates the original problem with BOOST_CLASS_VERSION that first came to my attention."	Bugs	new	Boost 1.46.0	mpl	Boost Development Trunk	Problem			jepler@… michael@… admin@…