Assembly segmentation fault ( array ) - arrays

Question

beginner in assembly here (IA-32 assembly). I keep getting a seg fault when compiling in gcc, I'm guessing its attempting to access forbidden memory, but I can't pin point it down. The task was to find the greatest common denominator of an array. I figured implementing this via an array with a side function gcd (returns the gcd of 2 numbers). Here is the code:
.intel_syntax noprefix
.text
.global GCD
GCD:
push edi
push esi
mov edi, [ebp + 12] # number of elements in the array
mov esi, [ebp + 8] #array address
mov eax, [esi] # place the first element of the array into eax
mov ecx, 1 # set the counter to 1
next_number: #accumulating the gcd of the entire array
cmp ecx, edi #if the counter reaches the max number of elements,
ja end #end the the loop
push [esi + 4*ecx] #calling the gcd function, pushing the numbers on the
push eax #stack, so gcd can pick them up
call gcd
add esp, 8
inc ecx #increment the counter
jmp next_number #next iteration
end:
pop esi
pop edi
leave
ret
And the gcd side function:
# The C algorithm for finding the gcd of 2 numbers implemented in IA-32
# while(y)
# {
# r = x % y;
# x = y;
# y = r;
# }
# return x;
.intel_syntax noprefix
.text
.global gcd
gcd:
enter 0,0
mov eax, [ebp + 8]
mov ecx, [ebp + 12]
loop:
cmp ecx, 0
je end
xor edx, edx
idiv ecx
mov eax, ecx
mov ecx, edx
jmp loop
end:
leave
ret