compiling errors related boost

问题:

When I use boost 1.52.1 and gcc-4.7.1 to compile my code, the following errors appear. It seems this is conflict between boost and c++ library. Could some know how to resolve this problem?

Many thanks for your reply.

c:\program files\mingw64\bin\../lib/gcc/x86_64-w64- 
mingw32/4.7.1/../../../../include/boost/math/policies
/error_handling.hpp: In function 'bool    boost::math::policies::
detail::check_overflow(std::complex<T>, 
R*, const char*, const Policy&)':c:\program    
files\mingw64\bin\../lib/gcc/x86_64-w64 mingw32/4.7.1
/../../../../include/boost/math/policies/error_handling.hpp:583:11: 
error: expected unqualified-id before numeric constant
c:\program files\mingw64\bin\../lib/gcc/x86_64-w64-mingw32
/4.7.1/../../../../include/boost/math/policies/error_handling.hpp:
584:49: error: lvalue required as unary '&' operand
 c:\program files\mingw64\bin\../lib/gcc/x86_64-w64-mingw32/4.7.1/
 ../../../../include/boost/math/policies/
 error_handling.hpp:584:107: error: 'im' was not declared in this
 scope c:\program files\mingw64\bin\../lib/gcc/x86_64-w64-mingw32
 /4.7.1/../../../../include/boost/math/policies/error_handling.
 hpp: In function 'bool boost::math::policies::detail::
 check_underflow(std::complex<T>, R*, const char*, const Policy&)':
 c:\program files\mingw64\bin\../lib/gcc/x86_64-w64-  mingw32
 /4.7.1/../../../../include/boost/math/policies
 /error_handling.hpp:602:11: error: expected unqualified-id before       
 numeric constant c:\program files\mingw64\bin\../lib/gcc/
 x86_64-w64 mingw32/4.7.1/../../../../include/boost/math/policies
 /error_handling.hpp:603:50: error: lvalue required as 
 unary '&' operand c:\program files\mingw64\bin\../lib/gcc/
 x86_64-w64 mingw32/4.7.1/../../../../include/boost/math/policies
 /error_handling .hpp:603:109: error: 'im' was not declared in 
 this scope c:\program files\mingw64\bin\../lib/gcc
 /x86_64-w64-mingw32/4.7.1/../../../../include/boost/math/policies/
 error_handling.hpp: In function 'bool boost::math::policies::
 detail::check_denorm(std::complex<T>, R*, const char*, 
  const Policy&)':c:\program files\mingw64\bin\../lib/gcc
 /x86_64-w64-mingw32/4.7.1/../../../../include/boost/
 math/policies/error_handling.hpp:622:11: error: expected 
 unqualified-id before numeric constant
 c:\program files\mingw64\bin\../lib/gcc/x86_64-w64-
 mingw32/4.7.1/../../../../include/boost/math/policies/
 error_handling.hpp:623:47: error: lvalue required as 
 unary '&' operand
 c:\program files\mingw64\bin\../lib/gcc/x86_64-w64-
 mingw32/4.7.1/../../../../include/boost/math/policies/
 error_handling.hpp:623:103: error: 'im' was not declared
 in this scope

The error appears in the code boost\math\policy\error_handling.hpp. But I am not sure when the program cite these functions. How does this error happen?

template <class R, class T, class Policy>
inline bool check_overflow(std::complex<T> val, R* result, const
char* function, const Policy& pol)
{
    typedef typename R::value_type r_type;
    r_type re, im;
    bool r = check_overflow<r_type>(val.real(), &re, function, pol) || check_overflow<r_type>(val.imag(), &im, function, pol);
    *result = R(re, im);
    return r;
}

 template <class R, class T, class Policy>
 inline bool check_underflow(std::complex<T> val, R* result, const char* function, const Policy& pol)
{
     typedef typename R::value_type r_type;
     r_type re, im;
     bool r = check_underflow<r_type>(val.real(), &re, function, pol) || check_underflow<r_type>(val.imag(), &im, function, pol);
     *result = R(re, im);
     return r;
}

回答1:

Given this two functions and this noisy error message I can say that type that was used as parameter R doesn't defines value_type. Because of that, type r_type and variables im and re is not defined. As result you get error: 'im' was not declared in this scope error.

Using only provided code I can saw that type R has this requirements:

• It must define type value_type
• It must have constructor R(value_type real, value_type imagine)

All this means that you use some boost library that uses internaly check_underflow/check_overflow functions incorrectly, with incompatible template argument, I guess.