Yes. Continuous means from some start to some end without break:
The water flowed continuously over the dam.
whereas continual means occurring repeatedly at intervals over a time span:
I continually lose at poker.
I should also mention that continual is often substituted for continuous, and would be correct in most contexts, however the converse is not generally true. That is to say,
The water flowed continually over the dam.
is okay, but you would (hopefully) not mean
I continuously lose at poker.
since that would imply that all you do all day long is play poker and lose.
"Subtle differences?" Hmmmm.
Well, there are some simple differences; dunno how subtle they are. Depends.
I agree with @augurar that (4) is ungrammatical, except for unstressed them.
That leaves (rearranging the order a little to show the Q-float direction of both):
- Both A and B are very good.
- A and B both are very good.
- A and B are both very good.
These all mean the same thing.
And here's a couple more sentences that these all come from, via conjunction reduction:
- A is very good.
- B is very good.
(or perhaps I should say "that all these come from", because that's Q-Float, too.)
Here's what's going on.
First, both means *all two;
that is, both has the same syntactic pattern as
all (integer) X, which only occurs with X > 2
-- all three of them, all 27 of them, both/all of them.
Second, both and all (and some, each, any, few, and quite a few more) are quantifiers.
Quantifiers are special words that normally modify noun phrases (as in [1.] above).
Third, in English there is a rule called "Quantifier-Float" that allows some (but by no means all)
quantifiers -- both or all in this case -- to detach themselves from the noun phrase that they bind,
and float away to an adverb niche in the verb phrase. Without, naturally, changing meaning.
That's what happened to [2.] and [3.] above;
those are the two available adverb niches in that verb phrase:
either right before the first auxiliary verb -- are -- or right after it.
That's all, really.
Best Answer
Neither of your examples is most correct; programs are compiled by compilers. GCC is doing the work to compile C code to machine code or whatever.
As for the subtle differences between your examples:
Compiled with is more correct than compiled in but both are awkward compared to the above. Using "with" to say "compiled using" is more appropriate if you are talking about the future:
"We will compile the C-code with GCC"
However, if you are talking about previously compiled code then "compiled by" makes the most sense as the work has been done, and it was performed by the compiler.
Finally, since GCC is a thing (ie a piece of software) rather than a place, "compiled in" doesn't make much sense in this case. When talking about building or making something, consider goods like a car being made in a specific country. This is why we tend to say that products are "made in China" instead of "made by China."
edit: As pointed out in the comments, we do tend to say that programs are written IN languages . Programs aren't written BY languages though, because the language is not doing the work, you are! That should also answer the additional sentences you added about writing IN C++ and then compiling that code WITH GCC to the point where the output was compiled BY GCC.