Newer versions of mCRL2 (tested using 202106.0) use C++17 features, and require compiler support for this.
The current build checks for and uses C++11.
m4/acx_mcrl2.m4 is updated to check compiler support for C++17 instead of C++11, and sets the appropriate flag for building the mCRL2 interfaces.
Finally, a namespace was missing from pbes-pins.cpp. This has been added such that ltsmin can successfully be compiled with the 202106.0 release of mCRL2, as well as the current development version.
Newer versions of mCRL2 (tested using 202106.0) use C++17 features, and require compiler support for this. The current build checks for and uses C++11.
In this pull request, I pull in a new version of m4/ax_cxx_compile_stdcxx.m4 from http://git.savannah.gnu.org/gitweb/?p=autoconf-archive.git;a=blob_plain;f=m4/ax_cxx_compile_stdcxx.m4 that supports checking for newer versions of the standard.
m4/acx_mcrl2.m4 is updated to check compiler support for C++17 instead of C++11, and sets the appropriate flag for building the mCRL2 interfaces.
Finally, a namespace was missing from pbes-pins.cpp. This has been added such that ltsmin can successfully be compiled with the 202106.0 release of mCRL2, as well as the current development version.