Hello,

this patch is obviously related to PR c++/2316 ("g++ fails to overload on 
language linkage") but seems fairly independent. Currently, the demangler 
recognizes 'Y' for extern "C" functions and ignores it. The patch makes it 
print extern "C" after the function type:
_Z1aIFYviEEvPT_
void a<void (int) extern "C">(void (*)(int) extern "C")

Writing it before the return type seems more natural, but it is ambiguous. 
I guess it could also be printed in the middle (next to the star that 
indicates a function pointer), but placing it like the cv-qualifiers of 
member functions seemed good (plus, that's where Oracle puts it in its 
implementation of c++filt).

Since g++ doesn't generate such mangling, the effect should be hard to 
notice ;-)

(Even if the patch was ok, I am not a committer)

2011-09-03  Marc Glisse  <marc.glisse@inria.fr>

         * include/demangle.h (demangle_component_type)
         [DEMANGLE_COMPONENT_EXTERN_C]: Handle extern "C".
         * libiberty/cp-demangle.c (d_dump): Likewise.
         (d_make_comp): Likewise.
         (d_function_type): Likewise.
         (d_print_comp): Likewise.
         (d_print_mod_list): Likewise.
         (d_print_mod): Likewise.
         (d_print_function_type): Likewise.
         * libiberty/testsuite/demangle-expected: Test it.

-- 
Marc Glisse