Compiler compatibility test

default_ctr.cpp

#include <map>
#include <string>

using namespace std;

// This is OK.
void func(map<string,string> a=map<string,string>()) {
  return;
}

// This is bad.
class Foo {
  void bar(map<string,string> a=map<string,string>()) {
    return;
  }
};

int main(int argc, char **argv) {
  Foo foo;
  return 0;
}

Error with Apple LLVM g++ compmiler.
$ g++ --version
i686-apple-darwin11-llvm-g++-4.2 (GCC) 4.2.1 (Based on Apple Inc. build 5658) (LLVM build 2336.11.00)
Copyright (C) 2007 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

$ g++ -Wall def_ctr.cpp
def_ctr.cpp:11: error: expected ‘,’ or ‘...’ before ‘>’ token
def_ctr.cpp:11: error: wrong number of template arguments (1, should be 4)
/usr/include/c++/4.2.1/bits/stl_map.h:93: error: provided for ‘template<class _Key, class _Tp, class _Compare, class _Alloc> class std::map’
def_ctr.cpp:11: error: default argument missing for parameter 2 of ‘void Foo::bar(std::map<std::basic_string<char, std::char_traits, std::allocator >, std::basic_string<char, std::char_traits, std::allocator >, std::less<std::basic_string<char, std::char_traits, std::allocator > >, std::allocator<std::pair<const std::basic_string<char, std::char_traits, std::allocator >, std::basic_string<char, std::char_traits, std::allocator > > > >, std::string)’
def_ctr.cpp: In function ‘int main(int, char**)’:
def_ctr.cpp:17: warning: unused variable ‘foo’

Works with Linux g++

$ g++ --version
g++ (GCC) 4.4.5 20110214 (Red Hat 4.4.5-6)
Copyright (C) 2010 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.