function overload in C

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1

Hi,

I’m trying to implement an overloading behavior to some of our builtin functions, and came across the following comment in SemaExpr.cpp

// Check for overloaded calls. This can happen even in C due to extensions.

If (Fn->getType() == Context.OverloadTy) { ….

I was wondering which C extensions is this referring to?

Thanks

Ali

2

http://clang.llvm.org/docs/LanguageExtensions.html#function-overloading-in-c

#include <stdio.h>
void __attribute__((overloadable)) onearg(int i) { printf("Arg is int: %d\n", i); }
void __attribute__((overloadable)) onearg(char *s) { printf("Arg is string: %s\n", s); }

int main() {
    onearg(1);
    onearg("String");
    return 0;
}

$ clang test.c && ./a.out
Arg is int: 1
Arg is string: String