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    <head>
      <base href="http://llvm.org/bugs/" />
    </head>
    <body><table border="1" cellspacing="0" cellpadding="8">
        <tr>
          <th>Bug ID</th>
          <td><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW --- - strcmp call modifies constant value in adjacent struct"
   href="http://llvm.org/bugs/show_bug.cgi?id=19661">19661</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>strcmp call modifies constant value in adjacent struct
          </td>
        </tr>

        <tr>
          <th>Product</th>
          <td>clang
          </td>
        </tr>

        <tr>
          <th>Version</th>
          <td>3.4
          </td>
        </tr>

        <tr>
          <th>Hardware</th>
          <td>PC
          </td>
        </tr>

        <tr>
          <th>OS</th>
          <td>Linux
          </td>
        </tr>

        <tr>
          <th>Status</th>
          <td>NEW
          </td>
        </tr>

        <tr>
          <th>Severity</th>
          <td>normal
          </td>
        </tr>

        <tr>
          <th>Priority</th>
          <td>P
          </td>
        </tr>

        <tr>
          <th>Component</th>
          <td>Static Analyzer
          </td>
        </tr>

        <tr>
          <th>Assignee</th>
          <td>kremenek@apple.com
          </td>
        </tr>

        <tr>
          <th>Reporter</th>
          <td>pspacek@redhat.com
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>llvmbugs@cs.uiuc.edu
          </td>
        </tr>

        <tr>
          <th>Classification</th>
          <td>Unclassified
          </td>
        </tr></table>
      <p>
        <div>
        <pre>Created <span class=""><a href="attachment.cgi?id=12482" name="attach_12482" title="minimal test case">attachment 12482</a> <a href="attachment.cgi?id=12482&action=edit" title="minimal test case">[details]</a></span>
minimal test case

Static analyzer thinks that strcmp() modifies memory adjacent to strcmp()
parameters. The problem doesn't happen if I use strcasecmp() instead of
strcmp(). Please see attached minimal example and report file.

Excerpt:

18    switch (setting->type) {
        Control jumps to 'case ST_STRING:' at line 19
19    case ST_STRING:
20        /* strcmp triggers the error */
21        if (strcmp(setting->value_char, value) == 0)
        Taking false branch
22        /* but strcasecmp doesn't trigger the error! */
23        //if (strcasecmp(setting->value_char, value) == 0)
24        return 1;
25    break;
...

33    switch (setting->type) {
    Control jumps to 'case ST_UNSIGNED_INTEGER:' at line 37

Apparently, analyzer thinks that setting->type was changed in strcmp() call.

Please see attached files for structure definitions etc.

Have a nice day!</pre>
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