[Bug c++/109755] New: -Wunused-function underline points at a class, not the unused method itself

["slyfox at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109755

            Bug ID: 109755
           Summary: -Wunused-function underline points at a class, not the
                    unused method itself
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: slyfox at gcc dot gnu.org
  Target Milestone: ---

Noticed when reduced example manually. Was a bit confused by an underline under
the class and not the method:

// $ cat a.cc
namespace {
    struct Foo {
        void m1();
        void m2();
    };
    void Foo::m1() {}
    void Foo::m2() {}
}

int main() {
    Foo o;
    o.m1();
}

$ gcc -c a.cc -Wall
a.cc:7:10: warning: 'void {anonymous}::Foo::m2()' defined but not used
[-Wunused-function]
    7 |     void Foo::m2() {}
      |          ^~~

Here it's not visible, but m2 is correctly highlighted in 'void
{anonymous}::Foo::m2()' string (good). But the underlying cursor points at the
'Foo' only. I think it should point at the whole 'Foo::m2' instead.

For example:

    7 |     void Foo::m2() {}
      |          ^~~~~~~

WDYT?

GCC is built from r14-539-g143e6695b20d35.

$ gcc -v
Using built-in specs.
COLLECT_GCC=/<<NIX>>/gcc-14.0.0/bin/gcc
COLLECT_LTO_WRAPPER=/<<NIX>>/gcc-14.0.0/libexec/gcc/x86_64-unknown-linux-gnu/14.0.0/lto-wrapper
Target: x86_64-unknown-linux-gnu
Configured with:
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 14.0.0 99999999 (experimental) (GCC)