This option enables or disables the recognition of guiding declarations for template functions in C++.
A guiding declaration is a function declaration that matches an instance of a function template but has no explicit definition because its definition derives from the function template.
If --no_guiding_decls is combined with --old_specializations,
a specialization of a nonmember template function is not recognized.
It is treated as a definition of an independent function.
Note
The option --guiding_decls is provided only
as a migration aid for legacy source code that does not conform
to the C++ standard. Its use is not recommended.
Mode
template <class T> void f(T)
{
...
}
void f(int);
When regarded as a guiding declaration, f(int) is
an instance of the template. Otherwise, it is an independent function
so you must supply a definition.
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