different bewteen gcc -fPIC -mlong-calls and clang -fPIC -mlong-calls

[LukeSTM]

demo:

#include <stdio.h>
int main ()
{
    printf("hello");
    return 0;
}

compile option: -fPIC -mlong-calls
target: armv7

https://godbolt.org/z/MzdPY3oTs

Hi, i am new to compiler.

In some scenarios, using dlopen to load so compiled with gcc -fPIC -mlong-calls is faster than so compiled with clang -fPIC to generate .and when i use clang -fPIC -mlong-calls compile same code, clang still slower than gcc.

i want know why gcc use GOT and clang not use GOT.

[hstk30-hw]

In fact, -fPIC and -mlong-calls is not compatile in llvm(maybe failed when linking).

BTW, it's a trade-off in your case. The shared object compilerd by GCC is faster than llvm when use dlopen， but the runtime performance is slower.
So does the speed of dlopen is your biggest concern? Not the runtime performance?