what's the right way to use custom entry point

[Cong Monkey]

Hi,

I want use custom entry point, but it's very strange!

entry_point_test.c file:

int sayhello(int argc, char** argv)
{
    return 0;
}

if I do:
   cc  ../entry_point_test.c  -o entry_point_test -Wl,-esayhello
then I get:
   /usr/lib/gcc/x86_64-linux-gnu/6/../../../x86_64-linux-gnu/crt1.o:
In function `_start':
(.text+0x20): undefined reference to `main'
collect2: error: ld returned 1 exit status

if I do:
   cc  ../entry_point_test.c  -o entry_point_test -Wl,-esayhello
-nostartfiles #cc works
   ./a.out
then I get:
   # Segmentation fault

anyone can help what should I do?

Tks