User-Level Documentation

• GCC Installation Instructions (also in PDF)
• GCC Manual (also in PDF and in monochromatic PDF)
• GNU Fortran Manual (also in PDF)
• CPP Manual (also in PDF)
• GDC Manual (also in PDF)
• GNAT Reference Manual (also in PDF) - already uses Sphinx
• GNAT User's Guide for Native Platforms / Unix and Windows (also in PDF) - already uses Sphinx
• GCCGO Manual (also in PDF)
• GNU Offloading and Multi Processing Runtime Library Manual (also in PDF)
• libstdc++-v3 Documentation
• GCC Quad-Precision Math Library Manual (also in PDF)
• libgccjit documentation - already uses Sphinx
• Libitm Manual (also in PDF)

Internals Documentation

• GCC Internals Manual (also in PDF)
• CPP Internals Manual (also in PDF)
• GNU Fortran Internals Manual (also in PDF)
• Libiberty Manual (also in PDF)

Manual pages

• gcc.1
• gcov.1
• gcov-dump.1
• gcov-tool.1
• lto-dump.1
• gpl.1
• gfdl.1
• fsf-funding.1
• cpp.1
• gfortran.1
• gccgo.1
• gdc.1

Info pages

• install.info
• gcc.info
• gfortran.info
• cpp.info
• gccgo.info
• gdc.info
• libgomp.info
• libquadmath.info
• libitm.info
• gccint.info
• cppinternals.info
• gfc-internals.info
• libiberty.info

Experimental

• Demo (also in PDF)
• Modula-2 Manual (experimental) (also in PDF)