Is this a bug in clang++/g++? [duplicate]

Question

Given:

void function(int*=0) {}
int main() {
}

clang (3.8.0):

test.cc:1:18: error: expected ')'
void function(int*=0) {
                 ^

g++ (5.4.0):

test.cc:1:18: error: expected ‘,’ or ‘...’ before ‘*=’ token
 void function(int*=0) {
                  ^    

If I change it to (note the spacing):

void function(int* = 0) {}
int main() {
}

Obviously it's getting confused whether I'm typing T* = 0 or T *= 0, is this a bug or expected?

Answer 1

*= is one operator, like += is. So x *= 2; is the same as x = x * 2;

You want * = to be lexed as two tokens (conceptually in C++, lexing happens before, and nearly independently, of parsing; read about C++ translation phases).