I noticed that gdb/cp-name-parser.y:cp_demangled_name_to_comp fails to grok this:

  "A::foo<void (int)>::func(int)"

which is a valid symbol name that can result from something like this:

~~~
#include <stdio.h>

namespace A
{
  template<typename T>
  struct foo
  {
    void func (int)
    {
      printf ("hello");
    }
  };
}

A::foo<void(int)> f1; // bad cases instantiated from this one here
A::foo<int> f2;

int
main (int argc, char **argv)
{
  f1.func (argc);
  f2.func (argc);

  return 0;
}
~~~

$ nm a.out | c++filt | grep func
000000000040062a W A::foo<void (int)>::func(int)
000000000040064c W A::foo<int>::func(int)

Running the symbol through test-cp-name-parser, we see:

 $ ./test-cp-name-parser 'A::foo<void (int)>::func(int)'
 syntax error, near `int)>::func(int)'

While the non-function-type one works OK:

 $ ./test-cp-name-parser 'A::foo<int>::func(int)'
 A::foo<int>::func(int)

A smaller reproducer:

 $ ./test-cp-name-parser 'foo<void(void)>'
 syntax error, near `void)>'

Function pointer types work OK:

 $ ./test-cp-name-parser 'foo<void (*) (void)>'