| Macros by Category | Revision History | 
   AC_CXX_MUTABLE
  
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.
http://autoconf-archive.cryp.to/ac_cxx_mutable.m4
    Copyright © 2008 Todd Veldhuizen
    Copyright © 2008 Luc Maisonobe <luc@spaceroots.org>
   
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