This code:
template<typename T>
void foo(int i, void(*f)(T*) = 0, T* a = 0) {}
int main() {
foo(5);
return 0;
}
gets you:
foo.cc: In function int main():
foo.cc:5: error: no matching function for call to foo(int)
So I figured that binding required an actual type, so I tried making it
explicit in the default values:
template<typename T>
void foo(int i, void(*f)(T*) = static_cast<void(*)(void*)>(0),
T* a = static_cast<void*>(0)) {}
int main() {
foo(5);
return 0;
}
But that gets me the same error.
I'm not sure whether argument types can be bound from default arguments in the
standard, but if they can't then I should get a diagnostic at the declaration
of the template. The actual message is cryptic and unhelpful.
--
Summary: Fails to identify template function with default args
Product: gcc
Version: 4.3.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: igodard at pacbell dot net
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40127
