AC_CXX_MUTABLE
, 
, 

2004-02-04

Todd Veldhuizen Luc Maisonobe <luc@spaceroots.org>

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cryp.to ac-archive's C++ Support (released)

If the compiler allows modifying class data members flagged with the mutable keyword even in const objects (for example in the body of a const member function), define HAVE_MUTABLE.

AC_DEFUN([AC_CXX_MUTABLE],
[AC_CACHE_CHECK(whether the compiler supports the mutable keyword,
ac_cv_cxx_mutable,
[AC_LANG_SAVE
 AC_LANG_CPLUSPLUS
 AC_TRY_COMPILE([
class A { mutable int i;
          public:
          int f (int n) const { i = n; return i; }
        };
],[A a; return a.f (1);],
 ac_cv_cxx_mutable=yes, ac_cv_cxx_mutable=no)
 AC_LANG_RESTORE
])
if test "$ac_cv_cxx_mutable" = yes; then
  AC_DEFINE(HAVE_MUTABLE,,[define if the compiler supports the mutable keyword])
fi
])