cpp(lib) vs. pedantic warnings vs. -Werror.

[cgd at sibyte dot com (Chris G. Demetriou)]

I'm using GCC sources checked out of the trunk as of 2001-01-03 00:00
GMT, and am wondering about some behaviour i'm seeing.

I'm invoking gcc as with various flags including -Wall -Werror.  The
-pedantic and -pedantic-errors flags are _not_ set.


cpp(lib)is emitting warnings of the form:

	form.h:330:8: warning: extra tokens at end of #endif directive

and _isn't_ causing them to be errors.

It looks like this is because those are issued via cpp_pedwarn(),
which in the end only causes an error out of pedantic_errors is set.


Comparing this with the behaviour of 'gcc' (or at least, a few stop
checks of its source 8-), it looks like GCC only calls pedwarn() in
places guarded by a check of pedantic.  Then, pedwarn() itself forces
an error of pedantic_errors (-pedantic-errors) is set, and the common
error handling code called by pedwarn() forces a warning to be
'upgraded' in all cases if warnings_are_errors (-Werror) is set.

I'd expect that cpp would behave in approximately the same way.  (The
nature of the error, i.e. whether or not that error should only show
up with -pedantic or not, is a different question.  Personally i'd
prefer if it was enabled, but...)

it looks like there are a bunch of calls in cpp to cpp_pedwarn() which
aren't guaded with checks of the CPP pedantic flag.  (but, there are
at least some calls which are guarded...)


So, I guess the question is, what's the expected behaviour in CPP, and
is this a known issue, and what's the Right solution?




chris