Jean Pierre CASSOU wrote
This file is included in the fpcbuild package (either zip, or tar.gz), in particular in subdirectory "install".
Apart from that - I assume that you already know that the source packages are not meant to be installed directly and that you need to have a previous FPC binary for the given target (or cross-compile from a different platform on which the FPC binary is already installed) in order to build the compiler, accompanying tools, run-time library and other packages first before installing them (and if you already do this, you can use 'make install' rather than install.sh; install.sh is only needed for installation of pre-built compiler, etc.).
Tomas