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Yesterday I ran into a g++ (3.4.6) compiler problem for code that I have been compiling without a problem using the Intel (9.0) compiler. Here's a code snippet that shows what happened: template<typename A, typename B> class Foo { }; struct Bar { void method ( Foo<int,int> const& stuff = Foo<int,int>() ); }; The g++ compiler error is: foo.cpp:5: error: expected `,' or `...' before '>' token foo.cpp:5: error: wrong number of template arguments (1, should be 2) foo.cpp:2: error: provided for `template<class A, class B> struct Foo' foo.cpp:5: error: default argument missing for parameter 2 of `void Bar::method(const Foo<int, int>&, int)' Apparently, the default argument is not accepted when written this way, and the compiler assumes that instead of the second template argument a new function argument is specified, for which it then expects a default value because the stuff argument has one. I can help the compiler by creating a typedef, and then everything compiles fine: template<typename A, typename B> class Foo { }; struct Bar { typedef Foo<int,int> FooType; void method ( FooType const& stuff = FooType() ); }; So I can solve my problem, but I don't understand what is going on. Do I miss a C++ (template?) language feature here and am I doing something wrong, or is the g++ compiler wrong in not accepting the first piece of code? Note BTW that this also compiles ... template<typename A, typename B> class Foo { }; void method ( Foo<int,int> const& stuff = Foo<int,int>() );

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