Open file only if it's readable

plugin/vim-gdb.vim

@@ -16,23 +16,30 @@ function! Tapi_vimgdb_goto(bufnum, arglist)
     let session = s:sessions[session_id]
     " Go to source window
     noautocmd call win_gotoid(session['source_winid'])
-    " Open file if needed
-    if filename != expand('%:p')
-        execute 'edit' fnameescape(filename)
-    endif
-    " Update highlighted line
-    if session['current_line_matchid'] != -1
-        call matchdelete(session['current_line_matchid'])
-    endif
-    let session['current_line_matchid'] = matchaddpos('VimgdbCurrentLine', [line])
-    " Jump to current line if its not visible
-    let first_visible = line('w0')
-    let last_visible = line('w$')
-    if last_visible > first_visible && (line < first_visible || line > last_visible)
-        execute 'keepjumps normal!' line . 'G'
-    endif
-    " Switch back to debugger window
-    noautocmd call win_gotoid(bufwinid(a:bufnum))
+    try
+        " Open file if needed
+        if filename != expand('%:p')
+            " Do nothing when file is not readable
+            if !filereadable(filename)
+                return
+            endif
+            execute 'edit' fnameescape(filename)
+        endif
+        " Update highlighted line
+        if session['current_line_matchid'] != -1
+            call matchdelete(session['current_line_matchid'])
+        endif
+        let session['current_line_matchid'] = matchaddpos('VimgdbCurrentLine', [line])
+        " Jump to current line if its not visible
+        let first_visible = line('w0')
+        let last_visible = line('w$')
+        if last_visible > first_visible && (line < first_visible || line > last_visible)
+            execute 'keepjumps normal!' line . 'G'
+        endif
+    finally
+        " Switch back to debugger window
+        noautocmd call win_gotoid(bufwinid(a:bufnum))
+    endtry
 endfunction