check_no_effect.c

   1 /*
   2  * sparse/check_no_effect.c
   3  *
   4  * Copyright (C) 2010 Dan Carpenter.
   5  *
   6  * Licensed under the Open Software License version 1.1
   7  *
   8  */
   9
  10 #include "smatch.h"
  11
  12 static int my_id;
  13
  14 static void match_stmt(struct statement *stmt)
  15 {
  16         struct expression *expr;
  17
  18         if (stmt->type != STMT_EXPRESSION)
  19                 return;
  20         expr = stmt->expression;
  21         if (!expr)
  22                 return;
  23         switch(expr->type) {
  24         case EXPR_PREOP:
  25         case EXPR_POSTOP:
  26         case EXPR_STATEMENT:
  27         case EXPR_ASSIGNMENT:
  28         case EXPR_CALL:
  29         case EXPR_CONDITIONAL:
  30         case EXPR_SELECT:
  31         case EXPR_CAST:
  32         case EXPR_FORCE_CAST:
  33         case EXPR_COMMA:
  34                 return;
  35         }
  36         if (in_expression_statement())
  37                 return;
  38         sm_msg("warn: statement has no effect %d", expr->type);
  39 }
  40
  41 void check_no_effect(int id)
  42 {
  43         my_id = id;
  44         add_hook(&match_stmt, STMT_HOOK);
  45 }