3 added 77 characters in body
source | link

Python 2, 4343 42 bytes

def f(x):
 while anywhile"1'"in`map(n%2for n in bin,x)`:x.pop()

The function modifies its argument in place.

Thanks to @xnor for golfing off a byte in a really clever way!

Test it on Ideone.

Python, 43 bytes

def f(x):
 while any(n%2for n in x):x.pop()

The function modifies its argument in place.

Test it on Ideone.

Python 2, 43 42 bytes

def f(x):
 while"1'"in`map(bin,x)`:x.pop()

The function modifies its argument in place.

Thanks to @xnor for golfing off a byte in a really clever way!

Test it on Ideone.

2 added 90 characters in body
source | link

Python, 43 bytes

def f(x):
 while any(n%2for n in x):x.pop()

f modifies its argument in place The function modifies its argument in place. 

Test it on Ideone.

Python, 43 bytes

def f(x):
 while any(n%2for n in x):x.pop()

f modifies its argument in place. Test it on Ideone.

Python, 43 bytes

def f(x):
 while any(n%2for n in x):x.pop()

The function modifies its argument in place. 

Test it on Ideone.

1
source | link

Python, 43 bytes

def f(x):
 while any(n%2for n in x):x.pop()

f modifies its argument in place. Test it on Ideone.