<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=http://email.email.llvm.org/c/eJzFVU1zmzAQ_TVw0cAYYWJ84OA0SZtJnEnrunGOEhKgVJY8kiC1f31X-CMkMzmlkzJCEtrV7ts3uwvVbFtcK7sRhjNEt8g1wqKNti4YXQSjWePcxgbpLMBXMKSwzsYVZ9qQjdFPvHSxNjVIiCkb0XF7UIKF8Y7LYDx6_86aW0tqDrvFJLtcXn_PHtP56m716_7qajVefbucfHlIFzfL26X33sM5zPgclQ1RNUCuWlVOkGuR4a41CkldEok6YgShkiOhrOOEIV2hWmoKogDnz40oGwRx7rjRoCKcIFLsOAvwdOjn9vruBmJHr0moNaNaHoPYwfuT3o-f2FdaDS-XEgBGCUYyLlH0QKSEmf9xhuzlJ4gBnjzB6_G0agAGPTdcodbCruEG9LLz6OGVRpBd7G09EwPntcc6NKva9QcN72cMMebDg-hfP28oiypLPJodD9ILwpiBTPE87tWURtwYbex_ALPma222L1gWy_l89uPRMz_vRYuDrvFHwHGkq-gVt1FHZOsTs09dPKQ1eeH5U4NqFeOVUJAP73H8SaDqvliC9BzSWNZGKIZQ7LtLrFuHhlBO8pK4suEW-fqibW1DVqRsmk5JSFrXaFMw0glfsB1R9vc2bI0s3tSzcE1L41KvffOS3XGJDt0KPoW1bd_bsnSST8KmOMvIdMopTc7GrKJplZE8n4ySnCVljqegIgnl0hZQWlBL4cddigKPMIwkwWmWpOM4H-Ec02x0xtNpmWYYOi1fEyFjb8f3ptAUvUlPyqkNn4TEWlErzo8InXCSF3OitmgNriEV9knbc-r_C4cq7Nt2XwLH_DE27LEWPdC_gk_VZA>53787</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Many missed uninit bugs by address/memory sanitizers
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
      </td>
    </tr>

    <tr>
      <th>Assignees</th>
      <td>
      </td>
    </tr>

    <tr>
      <th>Reporter</th>
      <td>
          davidbolvansky
      </td>
    </tr>
</table>

<pre>
    Inspired by this post
https://lists.fedoraproject.org/archives/list/devel@lists.fedoraproject.org/message/S75EUIQ5Y3MXNXVPFFX4XHE7CW3SKULU/

+ changed func7 tu return local variable instead of global (which is zero initialized)

LINK: https://godbolt.org/z/TbP4jdGbf

clang-12 l.c -Wall -Wextra
variable 'j' is uninitialized when used here [-Wuninitialized]
warning: variable 'num' is uninitialized when used here [-Wuninitialized]

2/8

---------------------------------------------------------------------------------
clang-12 -fsanitize=address l.c
no errors
---------------------------------------------------------------------------------
clang-12 -fsanitize=memory l.c
SUMMARY: MemorySanitizer: use-of-uninitialized-value in func2

1/8
---------------------------------------------------------------------------------
clang-12 -fsanitize=undefined l.c
no errors

---------------------------------------------------------------------------------
clang-12 -g l.c ; valgrind  ./a.out 

valgrind catches all bugs
</pre>
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