strstr challenge

create the fastest C strstr function implementation.
Rules:
1.Must be portable between different architectures(ARM,x86/x86-64,MIPS)
2.Must handle strings of any length that C standard library strstr can handle.
3.Cannot rely on undefined behavior or platform specific code.
strstr reference: http://www.cplusplus.com/reference/cstring/strstr/

>>6
I don't think you do. Casting from a pointer to char to a pointer to int is still yielding an operation whose time complexity is directly proportional the the input N, that is to say asymptotic to O(N)