initial import of GCC 9.3.0. changes include:

- live patching support
- shell completion help
- generally better diagnostic output (less verbose/more useful)
- diagnostics and optimisation choices can be emitted in json
- asan memory usage reduction
- many general, and specific to switch, inter-procedure,
profile and link-time optimisations. from the release notes:
"Overall compile time of Firefox 66 and LibreOffice 6.2.3 on
an 8-core machine was reduced by about 5% compared to GCC 8.3"
- OpenMP 5.0 support
- better spell-guesser
- partial experimental support for c2x and c++2a
- c++17 is no longer experimental
- arm AAPCS GCC 6-8 structure passing bug fixed, may cause
incompatibility (restored compat with GCC 5 and earlier.)
- openrisc support

import GCC 6.4.0. see this url for details which are too large to
include here:

http://gcc.gnu.org/gcc-6/changes.html

the main visible changes appear to be:

- The default mode for C++ is now -std=gnu++14 instead of -std=gnu++98.
- The C and C++ compilers now support attributes on enumerators.
- Diagnostics can now contain "fix-it hints"
- more warnings (some added to -Wall)

initial import of GCC 4.5.3 sources. changes since 4.1 are way too numerous
to review, please see http://gcc.gnu.org/gcc-4.5/changes.html (and the 4.2,
4.3 and 4.4 versions, too.)

this includes the core, c++, objc and the non java/ada/fortran parts of the
testsuite.

import GCC 6.4.0. see this url for details which are too large to
include here:

http://gcc.gnu.org/gcc-6/changes.html

the main visible changes appear to be:

- The default mode for C++ is now -std=gnu++14 instead of -std=gnu++98.
- The C and C++ compilers now support attributes on enumerators.
- Diagnostics can now contain "fix-it hints"
- more warnings (some added to -Wall)

initial import of GCC 4.5.3 sources. changes since 4.1 are way too numerous
to review, please see http://gcc.gnu.org/gcc-4.5/changes.html (and the 4.2,
4.3 and 4.4 versions, too.)

this includes the core, c++, objc and the non java/ada/fortran parts of the
testsuite.

branches: 1.1.1;
Initial revision

initial import of GCC 4.5.3 sources. changes since 4.1 are way too numerous
to review, please see http://gcc.gnu.org/gcc-4.5/changes.html (and the 4.2,
4.3 and 4.4 versions, too.)

this includes the core, c++, objc and the non java/ada/fortran parts of the
testsuite.