Whirlwind Attack & Strength Surge

[Krodjin]

d20PFSRD wrote:

Whirlwind Attack (Combat)

You can strike out at every foe within reach.
Prerequisites: Dex 13, Int 13, Combat Expertise, Dodge, Mobility, Spring Attack, base attack bonus +4.
Benefit: When you use the full-attack action, you can give up your regular attacks and instead make one melee attack at your highest base attack bonus against each opponent within reach. You must make a separate attack roll against each opponent.
When you use the Whirlwind Attack feat, you also forfeit any bonus or extra attacks granted by other feats, spells, or abilities.

d20PFSRD wrote:

Strength Surge (Ex)

Benefit: The barbarian adds her barbarian level on one Strength check or combat maneuver check, or to her Combat Maneuver Defense when an opponent attempts a maneuver against her. This power is used as an immediate action.
Special: This power can only be used once per rage.

Okay, so I have done some searching and seems that there is a general consensus that you can substitute a Trip combat manoeuvre for the melee attack you make when using “Whirlwind Attack”.

Presuming that is in fact the case, what happens if you combine the Barbarian Rage power “Strength Surge” with “Whirlwind Attack” to make a trip?

Do you get to add your barbarian level to the check made against each/every opponent that is within reach, or just against one?

In my mind the ambiguity comes from the fact that Whirlwind Attack states “make one melee attack at your highest BAB against each opponent within reach” and Strength Surge grants the bonus on “one STR check or combat manoeuvre check”, but you still "make a separate attack roll against each opponent".

Thoughts?

I guess another way to pose this question is: is Whirlwind attack one attack or many?

[Jeff Merola]

Whirlwind attack is multiple attacks (one per person, not one that hits everyone). Note that you make a separate attack roll against each opponent.

So Strength Surge would boost one trip attempt, but not all of them.

[blahpers]

You don't make one melee attack with Whirlwind Attack*. You make N attacks, where N is the number of foes within reach. Each one can be an attack, disarm, trip, sunder, or other attack substitute. These are separate attacks. Strength Surge would apply to one of these attacks (provided it was a combat maneuver).

*unless there is exactly one foe within reach