In the Book
In the Movie
Gavroche climbs over the barricade to gather ammunition from the dead during the second attack.
Gavroche does so while there are National Guardsmen posted outside the barricade, who only attack once they see him.
Gavroche is killed by a single shot.
Gavroche is shot twice, the first shot not being lethal.
A cannonade is used by the National Guard against the barricade during the second attack, but proves ineffective.
The cannons are brought out during the final battle, and thin the barricade out enough for the National Guard to invade it.
Marius is described as being covered in blood by the time he is taken away by Valjean, having been incapacitated by a shot that broke his collarbone.
Marius is wounded, but appears comparatively unharmed.
Valjean escapes into the sewers by way of a loose grating in the ground.
Valjean enters the sewers through a grate found in a wall at the end of an alley.