The GNU Compiler Collection is free software. See the file COPYINGfor copying permission. The manuals, and some of the runtimelibraries, are under different terms; see the individual source filesfor details.
The directory INSTALL contains copies of the installation informationas HTML and plain text. The source of this information isgcc/doc/install.texi. The installation information includes detailsof what is included in the GCC sources and what files GCC installs.
See the file gcc/doc/gcc.texi (together with other files that itincludes) for usage and porting information. An online readableversion of the manual is in the files gcc/doc/gcc.info*.