[boost] Re: [FOREACH] new version available, testers needed

From: Eric Niebler (eric_at_[hidden])
Date: 2005-03-10 10:53:54

Inline ...

Martin Wille wrote:
> 
> I now get these errors for gcc 2.95.3:
> 
> regress.cpp:88: invalid operands `const 
> boost::foreach_detail_::auto_any_base &' and `int' to binary `operator !='

As I mentioned, gcc 2.95 accepts BOOST_FOREACH in some onstructs but not 
others. In particular, the compiler chokes when BOOST_FOREACH is in a 
function template, like above. Simpler uses are fine. I'd gladly accept 
a patch, but I'm not inclined to waste much more of my time on this 
ancient compiler.

> 
> gcc-4 without #defines:
> 
> /boost/head-regression/boost/boost/iterator/counting_iterator.hpp:32: 
> error: '(bool)(boost::is_integral<char>::value)' is not a valid template 
> argument for type 'bool' because it is a non-constant expression
> ../../../boost/foreach.hpp:281: error: '(size_t)((-1))' is not a valid 
> template argument for type 'unsigned int' because it is a non-constant 
> expression

Whoa. This is some pretty basic, legal C++ that gcc-4 is choking on. Has 
gcc-4 been released yet? If not, I'm going to wait for it to stabilize a 
bit.

> 
> gcc 3.2.3 without defines:
> 
> regress.cpp: In function `std::vector<int, std::allocator<int> >
>    to_vector_foreach_byval(Range&) [with Range = int[5]]':
> regress.cpp:132:   instantiated from here
> regress.cpp:88: no match for `bool ? boost::foreach_detail_::rvalue_probe :
>    int[5]' operator

I'm guessing that defining BOOST_FOREACH_NO_CONST_RVALUE_DETECTION makes 
this go away? That's probably the right fix. It looks like gcc-3.2 is 
choking on the fancy rvalue detection stuff. I'll fix this.

-- 
Eric Niebler
Boost Consulting
www.boost-consulting.com