16.4.2 Automake C++ support

Automake provides support for compiling C++ programs. In fact, it makes it practically trivial: files listed in a SOURCES primary may include `.c++', `.cc', `.cpp', `.cxx' or `.C' extensions and Automake will know to use the C++ compiler to build them.

For a project containing C++ source code, it is necessary to invoke the AC_PROG_CXX macro in `configure.in' so that Automake knows how to run the most suitable compiler. Fortunately, when little details like this happen to escape you, automake will produce a warning:

$ automake automake: Makefile.am: C++ source seen but CXX not defined in automake: Makefile.am: `configure.in'