The bug
Firing an arrow from a bow while riding in a minecart causes the minecart to break.
The fix
This can be fixed by checking if the shooter of the arrow is the rider and returning false
.
EntityMinecart.java (MCP)
public boolean attackEntityFrom(DamageSource source, float amount)
{
if (!this.worldObj.isRemote && !this.isDead)
{
if (source.getSourceOfDamage() instanceof EntityArrow)
{
EntityArrow arrow = (EntityArrow) source.getSourceOfDamage();
if(this.getPassengers().contains(arrow.shootingEntity))
{
return false;
}
}
}
}
Linked issues
is duplicated by
Attachments
Comments

They made it so that minecarts' hitbox is two blocks tall now, so that they can be pushed off rails. That's the only practical application for this, and it not only breaks shooting from a minecart, but it also breaks some machines, like Etho's mob sorter. Bug or not, this should be fixed.
Confirmed. In addition, if the rail is on a single block with a space below you will fall completely through the block and space. This is particularly dangerous for covered rail bridges in the nether.

Tested in 14w34c. Minecraft only breaks when bow is aimed at it. Arrow can easily be shot out of minecart during riding.

Confirmed for 1.8.

Still an issue in 1.8.1-pre2.
confirmed for 1.8.1 pre-3. Also affects boats when firing an arrow from inside them. This makes pvp between boats nearly impossible.
Confirmed for 15w45a.
Can't confirm you get stuck in the ground. It's fixed.
Confirmed for 1.13-pre8
Confirmed for 1.13
Confirmed for 18w30b
This happens to me a lot especially when you are aiming down far enough so it seems like the bow's arrow is just above the 'side' of the boat/minecart you are in, but you would clearly expect the projectile to travel over the edge of your minecart and to whatever target you're looking at.
This also happens to horses sometimes, a bug that was fixed in earlier updates but needs to be reopened because its still happening in 1.14.2: https://bugs.mojang.com/browse/MC-13727 Also when youre in a boat, the arrow you shoot can sometimes hit the other entity riding behind u in the boat, for example a parrot or dog. Haven't tested if a player riding in the boat will get hit. opened bug report on this: https://bugs.mojang.com/browse/MC-154485
Confirmed for 20w06a.
This has been fixed in 20w14a. Forward-resolving as a duplicate of MC-176195.
Confirmed.