dwarflint: Check for unused include directories in .debug_line

diff --git a/src/dwarflint.c b/src/dwarflint.c
index 88177d75500e48d8899d729709c943fbef6681fc..a6204271dfaee003b356e687249875451c3fdf4d 100644 (file)
--- a/src/dwarflint.c
+++ b/src/dwarflint.c
@@ -4505,12 +4505,16 @@ check_line_structural (struct section_data *data)
          }
 
       /* Include directories.  */
+      struct include_directory_t
+      {
+       const char *name;
+       bool used;
+      };
       struct include_directories_t
       {
        size_t size;
        size_t alloc;
-       const char **names;
-       bool used;
+       struct include_directory_t *dirs;
       } include_directories;
       memset (&include_directories, 0, sizeof (include_directories));
       while (!read_ctx_eof (&sub_ctx))
@@ -4527,8 +4531,9 @@ check_line_structural (struct section_data *data)
            break;
 
          // XXX high-level check for filename?
-         REALLOC (&include_directories, names);
-         include_directories.names[include_directories.size++] = name;
+         REALLOC (&include_directories, dirs);
+         include_directories.dirs[include_directories.size++] =
+           (struct include_directory_t){name, false};
        }
 
       /* File names.  */
@@ -4590,11 +4595,20 @@ check_line_structural (struct section_data *data)
                                     &where, "file size of file entry"))
            goto skip;
 
+         if (dir_idx != 0)
+           include_directories.dirs[dir_idx - 1].used = true;
+
          REALLOC (&files, files);
          files.files[files.size++]
            = (struct file_t){name, dir_idx, timestamp, file_size};
        }
 
+      for (size_t i = 0; i < include_directories.size; ++i)
+       if (!include_directories.dirs[i].used)
+         wr_message (mc_impact_3 | mc_acc_bloat | mc_line, &where,
+                     ": the include #%zd `%s' is not used.\n",
+                     i + 1, include_directories.dirs[i].name);
+
       /* Skip the rest of the header.  */
       if (ctx.ptr > program_start)
        {