This is inspired by the autobook sections on Windows DLL builds.
https://www.sourceware.org/autobook/autobook/autobook_137.html
The AC_C_CONST macro improves support for the C language 'const'
decoration in case the compiler does not understand it.
AC_PROG_INSTALL
AC_PROG_LN_S
AC_PROG_INSTALL
AC_PROG_LN_S
# Required for per-target flags or subdir-objects with C sources.
AM_PROG_CC_C_O
# Required for per-target flags or subdir-objects with C sources.
AM_PROG_CC_C_O