[Boost-users] Compile errors with Phoenix closures

From: Martin Apel (martin.apel_at_[hidden])
Date: 2008-06-13 04:50:32

Hi all,

I posted this issue a week ago to the Spirit mailing list only, but I 
got no reply. So I repost this onto the Boost mailing list as well:

I tried to compile a Spirit grammar parsing a real number using closures 
under Microsoft Visual C++ 2005. The same grammar compiles fine on Linux 
using GCC 4.x. Boost version is 1.35.0 in both cases. As far as I 
understood, the error is caused by an assertion inside the closure class 
template:
  closure_frame_t&        context()       { assert(frame!=0); return 
frame.get(); }                                 (line 352 of 
boost/spirit/phoenix/closures.hpp)

Even if I define NDEBUG, Phoenix closures don't compile, because the 
return statement after the assertion returns a pointer to a 
closure_frame_t and not a reference. From my point of view, this is not 
really a compiler issue, but a bug in the header file 
boost/spirit/phoenix/closures.hpp. I do not understand, why GCC compiles 
this without any errors, because I think the code should not compile at all.
Any help would be appreciated.

Martin

C:\Programme\boost\boost_1_35_0\boost/spirit/phoenix/closures.hpp(352) : 
error C2784: 'impl::make_binary3<phoenix::not_eq_op,BaseT0,BaseT1>::type 
phoenix::operator !=(const phoenix::actor<BaseT> &,const 
phoenix::actor<BaseT> &)' : could not deduce template argument for 
'const phoenix::actor<BaseT> &' from 
'phoenix::impl::closure_frame_holder<FrameT>'
3>        with
3>        [
3>            
FrameT=phoenix::closure_frame<phoenix::closure<double,phoenix::nil_t,phoenix::nil_t>> 

3>        ]
3>        
C:\Programme\boost\boost_1_35_0\boost/spirit/phoenix/operators.hpp(1869) 
: see declaration of 'phoenix::operator !='
3>        
C:\Programme\boost\boost_1_35_0\boost/spirit/phoenix/closures.hpp(352) : 
while compiling class template member function 
'phoenix::closure_frame<ClosureT> 
&phoenix::closure<T0,T1,T2>::context(void)'
3>        with
3>        [
3>            
ClosureT=phoenix::closure<double,phoenix::nil_t,phoenix::nil_t>,
3>            T0=double,
3>            T1=phoenix::nil_t,
3>            T2=phoenix::nil_t
3>        ]
3>        
C:\Programme\boost\boost_1_35_0\boost/spirit/attribute/closure.hpp(226) 
: see reference to class template instantiation 
'phoenix::closure<T0,T1,T2>' being compiled
3>        with
3>        [
3>            T0=double,
3>            T1=phoenix::nil_t,
3>            T2=phoenix::nil_t
3>        ]
3>        E:\ma\new_arch\base/SpiritSupport.h(67) : see reference to 
class template instantiation 'boost::spirit::closure<DerivedT,T0>' being 
compiled
3>        with
3>        [
3>            DerivedT=NSBase::ExtRealParserClosure,
3>            T0=double
3>        ]
3>C:\Programme\boost\boost_1_35_0\boost/spirit/phoenix/closures.hpp(352) 
: error C2784: 'impl::make_binary2<phoenix::not_eq_op,T0,BaseT>::type 
phoenix::operator !=(T0,const phoenix::actor<BaseT> &)' : could not 
deduce template argument for 'const phoenix::actor<BaseT> &' from 'int'
3>        
C:\Programme\boost\boost_1_35_0\boost/spirit/phoenix/operators.hpp(1861) 
: see declaration of 'phoenix::operator !='
3>C:\Programme\boost\boost_1_35_0\boost/spirit/phoenix/closures.hpp(352) 
: error C2784: 'impl::make_binary1<phoenix::not_eq_op,BaseT,T1>::type 
phoenix::operator !=(const phoenix::actor<BaseT> &,T1)' : could not 
deduce template argument for 'const phoenix::actor<BaseT> &' from 
'phoenix::impl::closure_frame_holder<FrameT>'
3>        with
3>        [
3>            
FrameT=phoenix::closure_frame<phoenix::closure<double,phoenix::nil_t,phoenix::nil_t>> 

3>        ]
3>        
C:\Programme\boost\boost_1_35_0\boost/spirit/phoenix/operators.hpp(1853) 
: see declaration of 'phoenix::operator !='
3>C:\Programme\boost\boost_1_35_0\boost/spirit/phoenix/closures.hpp(352) 
: error C2676: binary '!=' : 
'phoenix::impl::closure_frame_holder<FrameT>' does not define this 
operator or a conversion to a type acceptable to the predefined operator
3>        with
3>        [
3>            
FrameT=phoenix::closure_frame<phoenix::closure<double,phoenix::nil_t,phoenix::nil_t>> 

3>        ]
3>C:\Programme\boost\boost_1_35_0\boost/spirit/phoenix/closures.hpp(352) 
: error C2440: 'return' : cannot convert from 
'phoenix::closure_frame<ClosureT> *' to 
'phoenix::closure_frame<ClosureT> &'
3>        with
3>        [
3>            
ClosureT=phoenix::closure<double,phoenix::nil_t,phoenix::nil_t>
3>        ]