Mass rename of C++ .c files to .cc suffix?

[Martin Jambor <mjambor@suse.cz>]

Hi,

Would anyone be terribly against mass renaming all *.c files (that are
actually C++ files) within the gcc subdirectory to ones with .cc suffix?

We already have 47 files with suffix .cc directly in the gcc
subdirectory and 160 if we also count those in (non-testsuite)
subdirectories, while the majority of our non-header C++ files still has
the .c suffix.

I have already missed stuff when grepping because I did not include *.cc
files and the inconsistency is also just ugly and must be very confusing
to anyone who encounters it for the first time.

Since we have switched to git, this should have quite small effect on
anyone who does their development on branches.  With Martin Liška we did
a few experiments and git blame, git rebase and even git gcc-backport
worked seamlessly across a rename.

I would be fine waiting with it until GCC 12 gets released but see
little value in doing so.

What do others think?  (Any important caveats I might have missed?)

Martin