contrib/coccinelle/unused.cocci

   1 // This rule finds sequences of "unused" declerations and uses of a
   2 // variable, where "unused" is defined to include only calling the
   3 // equivalent of alloc, init & free functions on the variable.
   4 @@
   5 type T;
   6 identifier I;
   7 // STRBUF_INIT, but also e.g. STRING_LIST_INIT_DUP (so no anchoring)
   8 constant INIT_MACRO =~ "_INIT";
   9 identifier MALLOC1 =~ "^x?[mc]alloc$";
  10 identifier INIT_ASSIGN1 =~ "^get_worktrees$";
  11 identifier INIT_CALL1 =~ "^[a-z_]*_init$";
  12 identifier REL1 =~ "^[a-z_]*_(release|reset|clear|free)$";
  13 identifier REL2 =~ "^(release|clear|free)_[a-z_]*$";
  14 @@
  15
  16 (
  17 - T I;
  18 |
  19 - T I = { 0 };
  20 |
  21 - T I = INIT_MACRO;
  22 |
  23 - T I = MALLOC1(...);
  24 |
  25 - T I = INIT_ASSIGN1(...);
  26 )
  27
  28 <... when != \( I \| &I \)
  29 (
  30 - \( INIT_CALL1 \)( \( I \| &I \), ...);
  31 |
  32 - I = \( INIT_ASSIGN1 \)(...);
  33 |
  34 - I = MALLOC1(...);
  35 )
  36 ...>
  37
  38 (
  39 - \( REL1 \| REL2 \)( \( I \| &I \), ...);
  40 |
  41 - \( REL1 \| REL2 \)( \( &I \| I \) );
  42 )
  43   ... when != \( I \| &I \)