feat: write small gdb patch to show libraries in unknown coredump backtraces

users/myuser/dev/0001-gdb-show-libraries-in-coredump-backtrace.patch

@@ -0,0 +1,33 @@
+diff --git a/gdb/stack.c b/gdb/stack.c
+index 7e45d59..cf38ff8 100644
+--- a/gdb/stack.c
++++ b/gdb/stack.c
+@@ -1376,7 +1376,27 @@ print_frame (const frame_print_options &fp_opts,
+     annotate_frame_function_name ();
+ 
+     string_file stb;
+-    gdb_puts (funname ? funname.get () : "??", &stb);
++
++	const char* from_where = "??";
++	if (funname) {
++		from_where = funname.get();
++	} else {
++		if (core_bfd) {
++			gdbarch_read_core_file_mappings(gdbarch, core_bfd,
++			[=] (ULONGEST count) { },
++			[&] (int num, ULONGEST start, ULONGEST end, ULONGEST file_ofs,
++			const char *filename, const bfd_build_id *build_id)
++			{
++				if (start <= pc && pc < end) {
++					from_where = filename;
++				}
++			});
++		} else {
++			// too much work for this small patch. Would need to inspect /proc/<pid>/maps
++	    }
++	}
++
++    gdb_puts (from_where, &stb);
+     uiout->field_stream ("func", stb, function_name_style.style ());
+     uiout->wrap_hint (3);
+     annotate_frame_args ();

users/myuser/dev/gdb.nix

@@ -3,9 +3,17 @@
   # Also make it the default gdb.
   pwndbgWithDebuginfod =
     (pkgs.pwndbg.override {
-      gdb = pkgs.gdb.override {
-        enableDebuginfod = true;
-      };
+      gdb =
+        (pkgs.gdb.override {
+          enableDebuginfod = true;
+        })
+        .overrideAttrs (_finalAttrs: previousAttrs: {
+          patches =
+            previousAttrs.patches
+            ++ [
+              ./0001-gdb-show-libraries-in-coredump-backtrace.patch
+            ];
+        });
     })
     .overrideAttrs (_finalAttrs: previousAttrs: {
       installPhase =